JP2009168886A - Image correction apparatus, image display system, and image correction method - Google Patents

Abstract

An image correction apparatus, an image display system, and an image correction method capable of preventing occurrence of luminance unevenness while suppressing a decrease in luminance are provided.
An image correction apparatus that corrects an image formed by display pixels using pixel light from a plurality of pixel light forming means includes a first pixel light forming means constituting the plurality of pixel light forming means. On the other hand, an output target value generation unit that generates an output target value corresponding to the input image signal, and the first of the plurality of pixel light forming units so that the luminance value of the display pixel becomes the output target value. Each pixel light constituting the remaining pixel light forming means is corrected by correcting the image signal for each pixel light forming means for controlling the luminance of the plurality of pixel light from the remaining pixel light forming means except the pixel light forming means And an image signal output unit for outputting to the forming means.
[Selection] Figure 5

Description

  The present invention relates to an image correction apparatus, an image display system, and an image correction method.

  In recent years, high-performance image display devices such as large-screen televisions and projectors have become widespread, and in these image display devices, color reproducibility and image quality are becoming more important. . Therefore, there is a high market demand for an image display device in which “uniformity of screen” is ensured in which pixels having the same signal value are displayed in the same color at any position in the display image.

  As a technique for ensuring such “screen uniformity”, for example, Patent Document 1 and Patent Document 2 disclose techniques for correcting color unevenness in a screen.

  In Patent Document 1, input / output characteristic data of an image display device is measured and the input / output characteristic data is used as reference input / output characteristic data in order to suppress the occurrence of color unevenness in all gradations that the input data can take. A technique for determining correction data for approaching all gradation levels is disclosed.

  Further, in Patent Document 2, in order to correct illuminance unevenness including color unevenness and brightness unevenness, a plurality of brightness unevenness generation amounts and color unevenness generation amounts are reduced from the brightness unevenness correction pattern and the color unevenness correction pattern. A technique is disclosed in which an illuminance unevenness correction pattern table corresponding to the illuminance level is generated to reduce the amount of illuminance unevenness generated.

JP 2006-38976 A JP 2006-153914 A

  However, when a projection-type image display device (projector) is employed as the image display device, a decrease in luminance is likely to occur at the peripheral portion in the projection image. When projecting onto the same screen using a plurality of such image display devices, even if the pixel signal values are corrected according to the correction data or the correction pattern using the techniques disclosed in Patent Document 1 and Patent Document 2, each image is displayed. There is a problem in that the luminance reduction in the peripheral portion in the projected image of the display device occurs as it is, and the luminance on the screen is uneven.

  The present invention has been made in view of the technical problems as described above, and one of its purposes is an image correction apparatus, an image display system, and an image correction capable of preventing the occurrence of luminance unevenness while suppressing a decrease in luminance. It is to provide a method.

  In order to solve the above-described problems, the present invention provides an image correction apparatus that corrects an image formed by display pixels using pixel light from a plurality of pixel light forming units, and includes the plurality of pixel light forming units. An output target value generation unit that generates an output target value corresponding to an input image signal, and the plurality of display pixels so that a luminance value of the display pixel becomes the output target value. Among the pixel light forming means, the image signal for each pixel light forming means for controlling the luminance of a plurality of pixel light from the remaining pixel light forming means excluding the first pixel light forming means is corrected, and the remaining pixels The present invention relates to an image correction apparatus including an image signal output unit that outputs to each pixel light forming unit constituting the light forming unit.

  According to the present invention, when displaying an image using a plurality of pixel light forming means, when the luminance of the pixel by the pixel light of one pixel light forming means does not reach the output target value, the remaining pixel light forming means By increasing the brightness using the plurality of pixel lights, it is possible to suppress the occurrence of a decrease in the brightness of the display image. In addition, since the luminance can be complemented by the pixel light forming means having sufficient capacity compared to the case where the luminance reduction is suppressed by the individual pixel light forming means, it is possible to efficiently prevent the occurrence of luminance unevenness while suppressing the luminance reduction. become.

  In the image correction apparatus according to the present invention, the remaining pixel light forming unit is formed on the screen based on the position of the display pixel formed on the screen by the pixel light from the first pixel light forming unit. N (n is an integer of 2 or more) display pixels can be formed in the order of close display pixel position.

  According to the present invention, when the luminance of the pixel does not reach the output target value, the luminance is complemented by using the n display pixels around the pixel. Occurrence can be prevented efficiently.

  In the image correction apparatus according to the present invention, the image signal output unit can correct the image signal so that each pixel light constituting the plurality of pixel lights uniformly increases in luminance.

  According to the present invention, since the luminance is evenly complemented to a plurality of pixels by the other pixel light forming means, it is possible to prevent the occurrence of luminance unevenness while suppressing a decrease in luminance. In addition, since the luminance increment is uniformly assigned to the plurality of pixels by the other pixel light forming means, an effect of preventing the occurrence of luminance unevenness while suppressing the decrease in luminance can be obtained with a small amount of calculation.

  In the image correction apparatus according to the present invention, the image signal output unit may include pixel light having a small luminance increment margin among the plurality of pixel lights with respect to pixel light having a large luminance increment margin. The image signal can be corrected so that the luminance increment becomes larger.

  According to the present invention, even if the luminance after the increment of another pixel that complements the luminance of the pixel exceeds the pixel maximum value, the insufficient luminance of the pixel is efficiently distributed and incremented. It becomes possible to prevent the later luminance from exceeding the pixel maximum value.

  In the image correction apparatus according to the present invention, the image signal output unit may increase the pixel light constituting each of the plurality of pixel lights according to a pixel value corresponding to the luminance of each pixel light. The image signal can be corrected.

  According to the present invention, it is possible to prevent the occurrence of luminance unevenness while maintaining the luminance distribution before correction and suppressing the decrease in luminance.

  In the image correction apparatus according to the present invention, the image signal output unit may form a display formed on the screen by the pixel light from the first pixel light forming unit for each pixel light constituting the plurality of pixel lights. With the pixel position as a reference, the image signal can be corrected so as to increase in accordance with the distance to the display pixel formed on the screen by each pixel light.

  According to the present invention, even when the pixel alignment by the pixel light from each pixel light forming unit is roughly adjusted, it is possible to prevent the occurrence of luminance unevenness while suppressing the decrease in luminance with high accuracy. .

  In addition, the present invention includes any one of the above-described image correction apparatus and the plurality of pixel light forming units whose luminance is controlled based on the image signal from the image correction apparatus. The present invention relates to an image display system for displaying an image using pixel light from the means.

  According to the present invention, it is possible to provide an image display system that prevents the occurrence of uneven brightness while suppressing a decrease in brightness.

  The present invention is also an image correction method for correcting an image formed by display pixels using pixel light from a plurality of pixel light forming means, wherein the first pixel light constituting the plurality of pixel light forming means An output target value generating step for generating an output target value corresponding to the input image signal to the forming means, and among the plurality of pixel light forming means so that the luminance value of the display pixel becomes the output target value The image signal for each pixel light forming unit that controls the luminance of a plurality of pixel lights from the remaining pixel light forming units other than the first pixel light forming unit is corrected to constitute the remaining pixel light forming unit. The present invention relates to an image correction method including an image signal output step for outputting to each pixel light forming unit.

  According to the present invention, it is possible to provide an image adjustment method for preventing the occurrence of luminance unevenness while suppressing a decrease in luminance.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments described below do not unduly limit the contents of the present invention described in the claims. Also, not all of the configurations described below are essential constituent requirements of the present invention.

Embodiment 1
The image correction apparatus according to the first embodiment of the present invention is applied to an image display system that displays using a plurality of images displayed by a plurality of image display apparatuses. This image display system can display a high-luminance image by displaying adjacent each pixel of a projected image on a screen projected by each image display device constituting a plurality of image display devices. Then, the image correction device outputs an image signal obtained by correcting the input image signal to each image display device so that the luminance of the output target value corresponding to the input image signal can be realized.

  FIG. 1 is a block diagram showing a configuration example of the image display system according to the first embodiment.

  The image display system 10 according to the first embodiment is projected by first to L-th (L is an integer of 2 or more) projectors (image display devices in a broad sense) PJ1 to PJL and first to L-th projectors PJ1 to PJL. An image measuring device 30 for obtaining a measurement value from the obtained image and an image correcting device (image processing device in a broad sense) 200 are included. Furthermore, the image display system 10 can include an image input unit (not shown) that inputs image signals to the first to L-th projectors PJ1 to PJL.

  The first to L-th projectors PJ1 to PJL each project an image on the screen SCR, and display one image with the pixels of each projection image adjacent to the screen SCR. Here, the projection may be performed so that the boundary between adjacent pixels of each projection image is in contact, or the adjacent pixels of each projection image may be projected at a given interval.

  Each projector has pixel light forming means for forming pixels of the projected image, and the luminance of the pixels is controlled by the image signal from the image correction apparatus 200. Such a pixel light forming unit includes a light modulation unit (light modulation unit) that modulates light from a light source, and a modulation rate (transmittance, light modulation rate) is controlled by an image signal from the image correction apparatus 200. Thus, the luminance of the pixel is controlled. Note that the first to Lth projectors PJ1 to PJL may have the same configuration or different configurations.

  The image measurement device 30 includes a camera 32 as an imaging unit and a measurement value processing unit 34. The camera 32 captures the image data of the projected image by capturing an image of the screen SCR projected by the first to Lth projectors PJ1 to PJL. As such a camera 32, for example, a digital still camera can be adopted. The measurement value processing unit 34 generates a measurement value based on the image data captured by the camera 32. The measurement value generated by the image measurement device 30 is supplied to the image correction device 200 as measurement data.

  The image correction apparatus 200 determines an output target value corresponding to an input image signal from the image input unit for each pixel light forming unit included in each projector. Then, the image correction apparatus 200 controls the luminance of the pixels by the pixel light forming unit included in each projector so that the luminance values of the pixels of the display image by the first to L-th projectors PJ1 to PJL become the output target values. The corrected image signal is corrected from the input image signal, and the corrected image signal is output to the first to L-th projectors PJ1 to PJL.

  More specifically, the image correction apparatus 200 corresponds to, for example, the first projector PJ1 (the first pixel light forming unit configuring the plurality of pixel light forming units) among the first to Lth projectors PJ1 to PJL. Thus, an output target value corresponding to the input image signal is generated. Then, the second to Lth projectors PJ2 to PJL (a plurality of pixel light formations) excluding the first projector PJ1 are set so that the luminance values of the display pixels by the first to Lth projectors PJ1 to PJL become the output target values. Second to L-th projectors by correcting the image signals for the respective projectors that control the brightness of the plurality of pixel lights from the at least one other pixel light forming means except the first pixel light forming means). Output to PJ2 to PJL.

  Further, when determining the output target value, the image correction apparatus 200 adjusts the correction amount of the image signal within the range of values that can be displayed by the projector, and displays the image using the corrected image signal using the correction amount. By doing so, processing for suppressing the occurrence of uneven color in the display screen is performed. More specifically, when the corrected image signal is not within the range of values that can be displayed by the projector, the hue and saturation of the pixel match the hue and saturation of a given reference pixel in the screen. As described above, the correction amount is adjusted within a range of values that can be displayed by the projector.

  FIG. 2 shows a block diagram of a configuration example of an image display device applied to each of the first to L-th projectors PJ1 to PJL in FIG. 2 also shows an image input unit 40 that supplies an input image signal to the image correction apparatus 200, and the first to L-th projectors PJ1 to PJL have the same configuration. To do.

  The image input unit 40 generates an image signal of an image projected by the projector. As the image input unit 40, for example, any of a scanner 42, a digital camera 44, and a personal computer (PC) 46 is employed. An image signal generated by such an image input unit 40 is output to the image correction apparatus 200 as an input image signal.

  The image correction device 200 determines an output target value corresponding to the input image signal from the image input unit 40 for each projector based on the measurement value measured by the image measurement device 30 of FIG. Then, the image correction apparatus 200 outputs an image signal obtained by correcting the input image signal to each projector so as to realize the output target value.

  The first to Lth projectors PJ1 to PJL include a light modulation unit 24 and a projection unit 26, respectively. The light modulator 24 is irradiated with light from a light source (not shown), and modulates the light transmission rate (transmittance, modulation rate) for each pixel based on the image signal from the image correction apparatus 200. As such a light modulation unit 24, a light valve constituted by a liquid crystal panel is employed. A liquid crystal panel is an electro-optical material liquid crystal that is hermetically sealed in a pair of transparent glass substrates. For example, a polysilicon TFT is used as a switching element to modulate the light transmission rate of each pixel corresponding to an image signal. . The light modulation unit 24 can generate pixel light that is a combination of a plurality of color lights with controlled transmission rates of the respective color lights, and has a function as pixel light forming means. The projection unit 26 includes a projection optical system that projects light from the light source modulated by the light modulation unit 24 onto the screen SCR.

  FIG. 3 shows a configuration example of the first projector PJ1 of FIG. Although FIG. 3 shows a configuration example of the first projector PJ1, the second to Lth projectors PJ2 to PJL can be configured in the same manner. In FIG. 3, the first projector PJ1 shows a so-called three-plate configuration example, but the projector according to the present invention is not limited to the so-called three-plate type.

  The first projector PJ1 includes a light source 110, integrator lenses 112 and 114, a polarization conversion element 116, a superimposing lens 118, an R dichroic mirror 120R, a G dichroic mirror 120G, a reflection mirror 122, an R field lens 124R, and a G field. It includes a lens 124G, a light modulation element 130, a relay optical system 140, a cross dichroic prism (light combining means in a broad sense) 160, and a projection lens 170 (a projection unit in a broad sense). In FIG. 3, since it is a three-plate type, as the light modulation element 130, an R liquid crystal panel 130R (first light modulation unit), a G liquid crystal panel 130G (second light modulation unit), and a B liquid crystal panel 130B ( A third light modulator is employed. The liquid crystal panels used as the R liquid crystal panel 130R, the G liquid crystal panel 130G, and the B liquid crystal panel 130B are transmissive liquid crystal display devices. The relay optical system 140 includes relay lenses 142, 144, and 146 and reflection mirrors 148 and 150.

  The light source 110 is composed of, for example, an ultra-high pressure mercury lamp, and emits light including at least R component light, G component light, and B component light. The light source 110 is driven and controlled by a light source control signal from a light source driving unit (not shown) in the image correction apparatus 200 or the first projector PJ1, for example. The integrator lens 112 has a plurality of small lenses for dividing the light from the light source 110 into a plurality of partial lights. The integrator lens 114 has a plurality of small lenses corresponding to the plurality of small lenses of the integrator lens 112. The superimposing lens 118 superimposes the partial light emitted from the plurality of small lenses of the integrator lens 112.

  The polarization conversion element 116 includes a polarization separation film and a λ / 2 plate, transmits p-polarized light, reflects s-polarized light, and converts p-polarized light to s-polarized light. The superimposing lens 118 is irradiated with the s-polarized light from the polarization conversion element 116.

  The light superimposed by the superimposing lens 118 is incident on the R dichroic mirror 120R. The R dichroic mirror 120R has a function of reflecting R component light and transmitting G component and B component light. The light transmitted through the R dichroic mirror 120R is applied to the G dichroic mirror 120G, and the light reflected by the R dichroic mirror 120R is reflected by the reflection mirror 122 and guided to the R field lens 124R.

  The dichroic mirror for G 120G has a function of reflecting G component light and transmitting B component light. The light transmitted through the G dichroic mirror 120G enters the relay optical system 140, and the light reflected by the G dichroic mirror 120G is guided to the G field lens 124G.

  In the relay optical system 140, in order to minimize the difference between the optical path length of the B component light transmitted through the G dichroic mirror 120G and the optical path length of the other R component and G component light, the relay lenses 142, 144, 146 is used to correct the difference in optical path length. The light transmitted through the relay lens 142 is guided to the relay lens 144 by the reflection mirror 148. The light transmitted through the relay lens 144 is guided to the relay lens 146 by the reflection mirror 150. The light transmitted through the relay lens 146 is applied to the B liquid crystal panel 130B.

  The light applied to the R field lens 124R is converted into parallel light and is incident on the R liquid crystal panel 130R. The R liquid crystal panel 130R functions as a light modulation element (light modulation unit), and the transmittance (passage rate, modulation rate) changes based on the R image signal. Therefore, the light (first color component light) incident on the R liquid crystal panel 130R is modulated based on the R image signal, and the modulated light is incident on the cross dichroic prism 160.

  The light applied to the G field lens 124G is converted into parallel light and is incident on the G liquid crystal panel 130G. The G liquid crystal panel 130G functions as a light modulation element (light modulation unit), and the transmittance (passage rate, modulation rate) changes based on the G image signal. Therefore, the light (second color component light) incident on the G liquid crystal panel 130G is modulated based on the G image signal, and the modulated light is incident on the cross dichroic prism 160.

  The B liquid crystal panel 130B irradiated with the light converted into parallel light by the relay lenses 142, 144, and 146 functions as a light modulation element (light modulation unit), and has a transmittance (passage rate) based on the B image signal. , Modulation rate) is changed. Therefore, the light (third color component light) incident on the B liquid crystal panel 130B is modulated based on the B image signal, and the modulated light is incident on the cross dichroic prism 160.

  The modulation ratios of the R liquid crystal panel 130R, the G liquid crystal panel 130G, and the B liquid crystal panel 130B are controlled independently for each color component by a given light modulation element control signal.

  The cross dichroic prism 160 as a light combining unit has a function of outputting combined light obtained by combining incident light from the R liquid crystal panel 130R, the G liquid crystal panel 130G, and the B liquid crystal panel 130B as outgoing light. The projection lens 170 as a projection unit is a lens that enlarges and forms an output image on the screen SCR.

  In the first embodiment, the pixels of the projected images by the first to Lth projectors PJ1 to PJL each having the above-described configuration are displayed on the screen so as to be adjacent to each other. Therefore, the image display system according to the first embodiment includes an image correction device and a plurality of pixel light forming units whose luminance is controlled based on an image signal from the image correction device. The image using the pixel light from can be displayed.

  For example, the first projector PJ1 has one pixel light forming unit. The pixel light forming means includes first to third light modulation units that are an R liquid crystal panel 130R, a G liquid crystal panel 130G, and a B liquid crystal panel 130B, and the modulation from the first to third light modulation units. The light can be synthesized and emitted as pixel light. The first light modulation unit modulates the light of the first color component based on the image signal of the first color component, and the second light modulation unit performs the first modulation based on the image signal of the second color component. The light of the second color component is modulated, and the third light modulation unit modulates the light of the third color component based on the image signal of the third color component.

  FIG. 4 is a schematic explanatory diagram illustrating an example of pixels of a display image on the screen according to the first embodiment. FIG. 4 shows an example of the pixels of the display image by the first and second projectors PJ1 and PJ2, but the same applies to the pixels of the display image by the first to L-th projectors PJ1 to PJL.

  As shown in FIG. 4, in the first embodiment, a pixel row arranged in the horizontal direction of the image projected by the second projector PJ2 between two pixel rows arranged in the horizontal direction of the image projected by the first projector PJ1. The first and second projectors PJ1 and PJ2 are adjusted so that. The pixels of the image projected by the first projector PJ1 are composed of R pixels, G components, and B component sub-pixels. The pixels of the image projected by the second projector PJ2 are composed of R pixels, G components, and B component sub-pixels. That is, when displaying a display image using pixel light from the pixel light forming means included in the first projector PJ1 and pixel light from the pixel light forming means included in the second projector PJ2, two pixel light forming means are displayed. Is adjusted so that the pixels of the displayed image are adjacent to each other.

  In FIG. 4, the display pixel DP2 by the second projector PJ2 is displayed shifted in the horizontal direction with respect to the display pixel DP1 by the first projector PJ1.

  Here, the pixel of the display image has a bright spot which is an image on the screen of the pixel of the light modulation means included in the projector, and the pixel of the display image is associated with the pixel of the light modulation element. That is, adjustment is made so that the position of the bright spot which is an image on the screen of the pixel of the light modulation means included in the two pixel light forming means is shifted.

  Thereby, according to the first embodiment, the brightness of the projected image on the screen can be improved even when the brightness of the projected images of the first and second projectors PJ1 and PJ2 is low.

  In FIG. 4, the pixels of the projection image of the first projector PJ1 and the pixels of the projection image of the second projector PJ2 are displayed side by side, but both pixels overlap in at least a part of the area. May be.

  FIG. 5 is a block diagram illustrating a configuration example of the image correction apparatus 200 according to the first embodiment.

  The image correction apparatus 200 includes an output target value generation unit 210 and an image signal output unit 220. The output target value generation unit 210 receives an input image signal from the image input unit 40 and generates an output target value corresponding to the input image signal for each pixel light forming unit constituting the plurality of pixel light forming units. . The image signal output unit 220 controls the luminance of the pixel light from each pixel light forming unit so that the luminance value of the pixel of the display image using the pixel light from the plurality of pixel light forming units becomes the output target value. The image signal is corrected and output to a plurality of pixel light forming means. More specifically, the output target value generation unit 210 generates an output target value corresponding to the input image signal for the first pixel light forming unit constituting the plurality of pixel light forming units, and outputs the image signal. The remaining portion of the plurality of pixel light forming units excluding the first pixel light forming unit so that the luminance value of the display pixel using the pixel light from the plurality of pixel light forming units becomes the output target value. Correcting the image signal for each pixel light forming means for controlling the luminance of the plurality of pixel lights from the at least one pixel light forming means, to each pixel light forming means of the remaining at least one pixel light forming means Can be output.

  That is, as an image correction method for correcting display pixels using pixel light from a plurality of pixel light forming means, it corresponds to an input image signal with respect to the first pixel light forming means constituting the plurality of pixel light forming means. An output target value generating step for generating the output target value, and the remaining of the plurality of pixel light forming means excluding the first pixel light forming means so that the luminance value of the display pixel becomes the output target value The image signal for each pixel light forming unit that controls the luminance of the plurality of pixel lights from at least one pixel light forming unit is corrected and output to each pixel light forming unit of the remaining at least one pixel light forming unit. An image signal output step.

  For example, when the plurality of pixel light forming units include first and second pixel light forming units, the image signal output unit 220 uses the first pixel DP1 (see FIG. 4) does not reach the output target value, the brightness values of the plurality of second pixels DP2 (see FIG. 4) of the display image by the second pixel light forming unit corresponding to the first pixel are increased. Thus, the image signal for the second pixel light forming means is output.

  The plurality of second pixels DP2 are peripheral pixels of the first pixel DP1. The plurality of second pixels DP2 have been described as being formed by the second pixel light forming unit, but the plurality of second pixels DP2 are a plurality of pixel lights excluding the first pixel light forming unit. It may be formed by forming means.

  As a result, when displaying an image using a plurality of pixel light forming units, the remaining pixel light forming unit is used even when the luminance of the pixel is reduced due to the pixel light of one pixel light forming unit. By increasing the luminance using the pixel light, it is possible to suppress the occurrence of a decrease in the luminance of the display image and to make the luminance unevenness of the image using the plurality of pixel light forming means inconspicuous. In addition, since the luminance can be complemented (compensated) by the pixel light forming means having sufficient capacity, compared to the case where the luminance reduction is suppressed by the individual pixel light forming means, the occurrence of luminance unevenness can be efficiently suppressed while suppressing the luminance reduction. Can be prevented.

  Here, the image signal output unit 220 has the same pixel position as that of the pixel in which the output target value is generated in the coordinate system defined for the light modulation unit (light modulation unit) whose luminance is controlled for each pixel. An image signal for controlling the pixel modulation rate can be corrected and output. In addition, the image signal output unit 220 has the same pixel position as that of the pixel for which the output target value is generated in the screen coordinate system defined for the screen on which the display image using the plurality of pixel light forming units is projected. An image signal that controls the luminance of the pixel can be corrected and output.

  Furthermore, in the image correction apparatus 200, the output target value generation unit 210 can display (processable) the first projector PJ1 based on the measurement value of the image measurement apparatus 30 (or correction data corresponding to the measurement value). The correction amount of the input image signal is adjusted within a range of values. The image signal is corrected based on this correction amount.

  Here, the corrected image signal may not be in a range that can be displayed by the first projector PJ1. For example, when the input image signal is an RGB space signal and the number of bits of the pixel value represented by the image signal from the image input unit 40 is “8”, the pixel value represented by the corrected image signal is The maximum pixel value “255” that can be expressed in 8 bits may be exceeded. In such a case, the image signal can no longer be corrected. Therefore, in the first embodiment, when the corrected image signal is not in a range that can be displayed by the first projector PJ1, the output target value generation unit 210 sets the hue and saturation of the pixel to the reference position in the screen. Output saturation processing for adjusting the correction amount is performed so as to match the hue and saturation (for example, the center position of the screen).

  Thereby, before and after the correction of the image signal, the color difference can be almost eliminated as compared with the brightness difference, so that the occurrence of color unevenness (luminance unevenness) in the screen can be suppressed.

  The image signal output unit 220 includes an output saturation processing detection unit 222, an output target value update unit 224, and a correction signal output unit 226. The output saturation processing detection unit 222 determines whether or not the luminance should be complemented by other pixel light forming means, and the output saturation processing in the output target value generation unit 210 is performed by at least one of the peripheral pixels of the pixel. It is determined whether or not it has been performed. As a result, when the input image signal cannot be corrected in order to obtain the output target value, the above output saturation processing is performed, so that it is possible to easily determine whether the luminance should be complemented by other pixel light forming means. become.

  When the output saturation processing detection unit 222 detects that the output saturation processing has been performed on at least one of the peripheral pixels of the pixel, the output target value update unit 224 has pixel light included in another projector. In order to complement the luminance by the forming unit, a process for correcting the image signal for the pixel light forming unit is performed, and the output target value is updated. As a result, the output target value generation unit 210 uses the updated output target value again to correct the input image signal so that it can be displayed by the projector while detecting the presence or absence of output saturation processing. .

  The correction signal output unit 226 performs the output saturation processing when the output saturation processing detection unit 222 does not detect that the output saturation processing has been performed on at least one of the peripheral pixels of the pixel. It is determined that the output target value can be obtained, the image signal is corrected using the already adjusted correction amount, and the corrected image signal is output as a corrected image signal to each pixel light forming unit.

  In such an image correction apparatus 200, the output target value generation unit 210 generates an output target value based on the measurement value measured by the image measurement apparatus 30. The correction signal output unit 226 outputs a corrected image signal based on the measurement value. Therefore, the image correction apparatus 200 includes the measurement value table 230 and generates the output target value with reference to the storage information of the measurement value table 230.

  In the measurement value table (table in a broad sense) 230, the measurement values (measured pixel values) of the pixels displayed for all the pixels in the image based on the pixel values are stored for each projector. Therefore, the measurement value table 230 stores the measurement value (pixel value) of the reference pixel displayed based on each pixel value and the measurement value (pixel value) of the pixel displayed based on each pixel value. Is done. The measurement value table 230 may store correction data corresponding to the measurement value instead of the measurement value.

FIG. 6 is an explanatory diagram of pixel positions of an image from which measurement values stored in the measurement value table 230 of FIG. 5 are measured. In FIG. 6, for example, in the image IMG projected by the first projector PJ1, the position of each pixel of all the pixels of the image IMG can be defined with the horizontal direction as the x axis and the vertical direction as the y axis. Here, N (N is an integer of 2 or more) pixels are arranged in the horizontal direction, and M (M is an integer of 2 or more) pixels are arranged in the vertical direction. Therefore, the pixels (x ₀ , y ₀ ), (x ₁ , y ₀ ),..., (X _N−1 , y ₀ ), (x ₀ , y ₁ ),. ₀ , y ₂ ),..., (X ₀ , y _M−1 ),..., (X _N−1 , Y _M−1 ), the measured values measured by the image measuring device 30 are It is stored in the measurement value table 230.

  FIG. 7 is an explanatory diagram of measurement values stored in the measurement value table 230 of FIG.

In the measured value table 230, first, the measured value of the pixel displayed based on the pixel value “0” (or correction data corresponding to the measured value) is, for example, (x ₀ ) in the horizontal direction of the image IMG in FIG. , Y ₀ ), (x ₁ , y ₀ ), (x ₂ , y ₀ ), ..., (x _N-1 , y ₀ ), (x ₀ , y ₁ ), ..., (x _{N −1} , y _M−1 ). Subsequently, in the measurement value table 230, the measurement values of the pixels displayed based on the pixel value “1” are (x ₀ , y ₀ ), (x ₁ , y _0), of _{(x 2, y 0),} ···, (x N-1, y 0), (x 0, y 1), ···, (x N-1, y M-1) Stored in order. Thus, finally, the measured value table 230 displays the measured values of the pixels displayed based on the pixel value “255” in the horizontal direction of the image IMG in FIG. 6 (x ₀ , y ₀ ), (x ₁ , y _0), of _{(x 2, y 0),} ···, (x N-1, y 0), (x 0, y 1), ···, (x N-1, y M-1) Stored in order. As a result, the measured value table 230 stores the measured values of the pixels displayed for all the pixels in the image based on the pixel values.

  In the measurement value table 230, the measurement values of all the pixels as described above are stored for each projector.

  In FIG. 7, the data size of the measurement value stored in the measurement value table 230 and the data size of each measurement value are recognized in advance for each pixel value. Therefore, since the storage area for the measurement value of the desired pixel value at the desired pixel position can be specified from the measurement value group stored in the measurement value table 230, only the measurement value is stored in the measurement value table 230. Just keep it.

  As described above, the output target value generation unit 210 refers to the measurement value table 230 in which the measurement values of the pixels displayed based on the pixel values of the reference pixels for each projector are stored, and the pixel values of the pixels Can be generated as an output target value. Then, the correction signal output unit 226 obtains a correction amount corresponding to the output target value generated by the output target value generation unit 210 or the output target value updated by the output target value update unit 224, and uses the correction amount. To correct the image signal and output it.

  Further, the output target value generation unit 210 searches the measurement value table 230, and performs output saturation processing when it is detected that the measurement value corresponding to the output target value is stored in the measurement value table 230. Absent. On the other hand, the output target value generation unit 210 searches the measurement value table 230, and performs output saturation processing when it is detected that the measurement value corresponding to the output target value is not stored in the measurement value table 230. Thus, the correction amount of the pixel is adjusted so that the hue and saturation of the pixel match the hue and saturation of the reference pixel.

  In this way, the output target value is generated with reference to the table in which the measurement value for the reference pixel is stored, and it is determined whether or not the measurement value for the pixel is stored in the stored table. Thus, it becomes possible to determine whether or not the corrected pixel value obtained by correcting the pixel value of the pixel using the correction amount exceeds the maximum pixel value. Accordingly, it is possible to determine whether or not the corrected pixel value of the pixel has exceeded the maximum pixel value with a simple configuration without providing a new additional device.

  FIG. 8 shows a block diagram of a hardware configuration example of the image correction apparatus 200 according to the first embodiment.

  The image correction apparatus 200 includes a central processing unit (CPU) 80, a read only memory (ROM) 82, a random access memory (RAM) 84, and an interface (Interface: I / F). ) Circuit 86 and image processing circuit 88. The CPU 80, ROM 82, RAM 84, I / F circuit 86 and image processing circuit 88 are connected via a bus 90.

  The ROM 82 stores a program, and the CPU 80 that has read the program via the bus 90 can execute processing corresponding to the program. The RAM 84 serves as a working memory for the CPU 80 to execute processing, and a program to be read by the CPU 80 is temporarily stored. The I / F circuit 86 performs interface processing with each of the image input units 40, and performs input processing of input image signals from the image input unit 40. The image processing circuit 88 implements the image processing described above. The image processing circuit 88 can realize the image processing in the first embodiment while using the RAM 84 as a working memory with reference to programs and data stored in the ROM 82, for example.

  The image processing circuit 88 corrects the input image signal from the image input unit 40 via the I / F circuit 86 and performs processing to suppress the occurrence of color unevenness in the screen. In the image correction apparatus 200, the image processing circuit 88 has been described as dedicated hardware provided separately from the CPU 80. However, the function of the image processing circuit 88 is determined by the processing of the CPU 80 that reads a program stored in the ROM 82 or the RAM 84. It may be realized.

  A measurement value obtained by the image measurement device 30 or correction data corresponding to the measurement value is written in the ROM 82. For example, in the image display system 10, the measurement values of each projector are collected by repeating the following sequence for each projector.

  That is, first, the first projector PJ1 projects an evaluation image on the screen SCR. The image measurement device 30 takes in the projection image of the screen SCR as image data and generates a measurement value. Next, the projection of the second projector PJ2 and the imaging of the image measuring device 30 are performed. Thereafter, the projection of the projector and the imaging of the image measuring device 30 are repeated, and the image measuring device 30 performs the entire projection image for each projector. For pixels, measurement values corresponding to all pixel values are generated for each pixel. Then, the measurement value generated by the image measurement device 30 or the correction data corresponding to the measurement value is written in the ROM 82. Thereafter, when an image signal corresponding to the image is input from the image input unit 40, the image correction apparatus 200 obtains a correction amount for each pixel based on the measurement value (correction data) written in the ROM 82, and performs the correction. The image signal is corrected using the quantity and output.

  In FIG. 5, the functions of the output target value generation unit 210 and the image signal output unit 220 are realized by the image processing circuit 88 of FIG. 8 or the CPU 80 of FIG. 8 that reads the program and performs processing corresponding to the program. The functions of the measurement value table 230 of FIG. 5 are realized by the ROM 82 of FIG.

  Next, a processing example of the image correction apparatus 200 according to the first embodiment will be described. Hereinafter, the image correction apparatus 200 according to the first embodiment will be described as adjusting the correction amount of the pixel value of each color component in the RGB color space for each pixel. However, the present invention is not limited to this.

FIG. 9 shows a flowchart of a processing example of the image correction apparatus 200 according to the first embodiment.
FIG. 10 shows a flowchart of a processing example of the output target value determination processing of FIG.
FIG. 11 shows a flowchart of a processing example of the correction processing of each color component in FIG.
For example, the ROM 82 stores programs for realizing the processes shown in FIGS. 9, 10, and 11 in advance, and the CPU 80 having the function of the image processing circuit 88 or the image processing circuit 88 including a CPU (not shown). By reading a program stored in the ROM 82 and executing processing corresponding to the program, the processing shown in FIGS. 9, 10, and 11 can be realized by software processing.

  First, the image correction apparatus 200 waits until an input image signal from the image input unit 40 is input (step S100: N). When the input image signal from the image input unit 40 is input, the image correction apparatus 200 performs variable initialization processing (step S102). For example, in step S102, the variable i for designating one of the L projectors is set to “1”, and the variable indicating the ratio for reducing the output target value in the output saturation processing is set to “1.0”. Initialize variables that require processing, such as setting. Subsequently, since the variable i is “1”, the image correction apparatus 200 performs a process of determining an output target value for the first projector PJ1 corresponding to the input image signal (step S104).

  Although the processing content of step S104 will be described later, when the output saturation processing is performed, the output target value of each color component of RGB is reduced at the same ratio in order to eliminate the color difference compared to the brightness difference. Therefore, following step S104, the image correction apparatus 200 stores a variable indicating the reduction ratio of the output target value after the process of step S104 (step S106), and increments the variable i (step S108). As the reduction ratio of the output target value, the reduction ratio of the output target value in the i-th projector PJi is set in step S104. Then, it is compared whether or not the value of the variable i is greater than L (step S110). When the value of the variable i is equal to or less than L (step S110: N), the image correction apparatus 200 returns to step S104 and increments. The output target value for the projector specified by the variable i later is determined.

  Here, assuming that the luminance of the pixel of the first projector PJ1 is complemented by the corresponding pixel of the second to Lth projectors PJ2 to PJL, in step S110, the value of the variable i is greater than L (step S110). :), the image correction apparatus 200 has performed the output saturation processing when determining the output target value of the projector for all of the first to L-th projectors PJ1 to PJL in all the peripheral pixels of the pixel, or It is determined whether no output saturation processing has been performed (step S112). In step S112, the process can be simplified by referring to the value of the variable indicating the reduction ratio.

  When the output saturation processing is performed for determining the output target value in the first to L-th projectors PJ1 to PJL for all the peripheral pixels (step S112: Y), the luminance of the pixels by other projectors is complemented. Therefore, the process proceeds to the next process without performing the luminance complement processing, and an image signal corresponding to the output target value obtained at this time is obtained with reference to the measurement value table 230 and corrected. It outputs as an image signal (step S114). Similarly, for all the peripheral pixels, when the output saturation processing is not performed when determining the output target value in the first to L-th projectors PJ1 to PJL (step S112: Y), Since this means that luminance complementation is unnecessary, the process proceeds to the next process without performing the luminance complementation process, and the image signal corresponding to the output target value obtained at this time is referred to the measurement value table 230. And is output as a corrected image signal (step S114).

  When it is determined in step S112 that output saturation processing has been performed when determining an output target value in any one of the first to L-th projectors PJ1 to PJL for at least one of the peripheral pixels (step S112: N ) The image correction apparatus 200 performs luminance complementation processing using a plurality of pixels from other projectors (step S116), returns to step S102, and again uses the image signal after the luminance interpolation processing for all projectors. Re-determine the output target value. This luminance complement processing will be described later.

  In step S114, after outputting the corrected image signal, when all the pixels are finished (step S118: Y), a series of processing is finished (end), and when all the pixels are not finished (step S118: N), The process returns to step S100.

  As described above, according to the first embodiment, it is determined whether or not output saturation processing has been performed, and the luminance of a plurality of pixels by another projector is increased, thereby complementing the luminance of the pixels by the projector. Can do. As a result, it is possible to prevent the occurrence of uneven brightness while suppressing the decrease in brightness more efficiently than when suppressing the decrease in brightness with individual projectors.

  Next, step S104 in FIG. 9 will be described.

  In step S104, when the corrected pixel value exceeds the pixel value maximum value, the u ′ component and v ′ component of the pixel in the u′v ′ chromaticity diagram (CIE 1976 UCS chromaticity diagram) are the reference pixel u ′. The correction amount is adjusted so as to coincide with the component and the v ′ component. As a result, attention is paid to the u ′ component and the v ′ component of the commonly used chromaticity diagram, so that the pixel and the hue and saturation of the pixel match the hue and saturation of the reference pixel with a simple configuration. The amount of correction can be adjusted. Therefore, color unevenness can be made inconspicuous even when the corrected pixel value exceeds the limit value of the projector while using existing resources.

  Therefore, in the first embodiment, the correction amount is adjusted while reducing the output target value so that the correction pixel value does not exceed the maximum pixel value for the pixel value of each color component in the RGB space as follows. .

  As shown in FIG. 10, the image correction apparatus 200 first acquires an image signal from the image input unit 40 such as the scanner 42 as an input value (step S10). This image signal has a pixel value of each color component in the RGB space, for example.

  Next, the image correction apparatus 200 performs a correction process on the pixel value of the B component in the RGB space of the pixel (step S12).

  In the correction process of the B component pixel value, as shown in FIG. 11, the output target value generation unit 210 generates the B component output target value of the pixel (step S40). More specifically, the output target value generation unit 210 is an output pixel value when displayed based on each pixel value (input pixel value) in the reference pixel from the measurement value group stored in the measurement value table 230. A certain measured value is generated as an output target value function, and a measured value when the same pixel value as the pixel value of the pixel is set as an input pixel value is obtained as an output target value from the output target value function.

  FIG. 12 is an explanatory diagram of the output target value function of the B component in the first embodiment.

  In FIG. 12, the horizontal axis represents the B component input pixel value, the vertical axis represents the output value (measured value, physical quantity) corresponding to the B component output pixel value, and the output when the input pixel value is given to the reference pixel. This represents a change in pixel value. More specifically, in FIG. 12, the measurement value of the reference pixel is represented by the output target value function T1, and the measurement value of the pixel is represented by the function MB.

  Subsequent to step S40 in FIG. 11, the output target value generation unit 210 obtains a correction amount based on the measured value and the pixel value of the pixel, and corrects the pixel value of the pixel based on the correction amount. A pixel value is obtained (step S42). For example, when the input pixel value B1 of FIG. 12 is given, an input pixel value B2 for obtaining an output target value (PB1, PB2) corresponding to the input pixel value B1 in the pixel is obtained. Therefore, the correction amount is obtained from the difference between the pixel values B1 and B2.

  On the other hand, for example, when the input pixel value B3 of FIG. 12 is given, the output target value (PB3) corresponding to the input pixel value B3 in the pixel does not exist in the function MB. That is, even if the measurement value of the input pixel value B3 is searched for the pixel in the measurement value table 230, an output value cannot be obtained, resulting in a table search error. This is because the corrected pixel value obtained by correcting the input pixel value exceeds the pixel value maximum value, and is no longer able to be displayed by the first projector PJ1. Therefore, when the correction pixel value exceeds the pixel value maximum value, the correction amount is adjusted so that the correction pixel value does not exceed the pixel value maximum value.

  Therefore, following step S42 in FIG. 11, the output target value generation unit 210 compares the corrected pixel value obtained in step S42 with the maximum pixel value (step S44). When the corrected pixel value exceeds the maximum pixel value (step S44: Y), the output target value generation unit 210 performs control to reduce the output target value generated in step S40 (step S46), and returns to step S42. By step S46, the output target value becomes the function T2 in FIG. In step S42, a correction amount is obtained based on the reduced output target value and the pixel value of the pixel, and a correction pixel value obtained by correcting the pixel value of the pixel is obtained based on the correction amount.

  In this way, the process is repeated until the correction pixel value becomes equal to or less than the maximum pixel value in step S44. When the correction pixel value is equal to or less than the maximum pixel value (step S44: N), the image correction apparatus 200 ends a series of processes. (End).

  Returning to FIG. Subsequent to step S12, when the reduction control of the B component output target value is performed (step S14: Y), the correction pixel value becomes equal to or less than the maximum pixel value in step S44 of FIG. The reduction rate rb of the output target value of the B component at that time is acquired (step S16). Then, the image correction apparatus 200 uses the reduction ratio rb to calculate output target values for the R component and G component that are other color components of the pixel (step S18).

  Then, when the reduction control of the output target value of the B component is not performed in step S14 (step S14: N), the image correction apparatus 200 uses the output target value of the R component of the pixel as it is, and uses the R component output target value as it is. Correction processing is performed (step S20). On the other hand, when the reduction control of the B component output target value is performed in step S14 (step S14: Y), the image correction apparatus 200 sets the reduced output target value using the reduction ratio rb of the B component output target value. In step S20, R component correction processing is performed. Here, the reduced output target value is Tr × rb obtained by multiplying the output target value Tr of the R component of the pixel by rb.

  Since the R component correction process in step S20 is the same as the B component correction process in step S12, a detailed description thereof will be omitted. That is, in step S20, processing is performed as shown in FIG.

  FIG. 13 is an explanatory diagram of the output target value function of the R component in the first embodiment.

  In FIG. 13, as in FIG. 12, the horizontal axis represents the R component input pixel value, and the vertical axis represents the output value (measured value, physical quantity) corresponding to the R component output pixel value. This represents a change in the output pixel value when given. More specifically, in FIG. 13, the measurement value of the reference pixel is represented by the output target value function T10, and the measurement value of the pixel is represented by the function MR. FIG. 13 shows an example of the R component output target value when the reduction control of the B component output target value is performed in step S12. Also for the R component, as a result of being performed at the reduction rate rr of the output target value, a function T11 in FIG. 13 is obtained.

  Returning to FIG. Subsequent to step S20, when the reduction control of the R component output target value is performed (step S22: Y), the correction pixel value becomes equal to or less than the maximum pixel value as in step S16. The reduction ratio rr of the output target value of the R component at the time is acquired (step S24). Then, the image correction apparatus 200 uses the reduction ratio rr to calculate output target values for the B component and the G component, which are other color components of the pixel (step S26).

  Here, when the output target value of the B component calculated in step S26 is different from the output target value used in step S12 (step S28: Y), the process returns to step S12, and the B component obtained in step S26 is obtained. Using the output target value, each component is corrected again in order from the B component.

  When the output target value of the B component calculated in step S26 is the same as the output target value used in step S12 (step S28: N), or the reduction control of the output target value of the R component is not performed in step S22. At this time (step S22: N), the image correction apparatus 200 performs a G component correction process using the output target value of the G component of the pixel or the reduced output target value obtained in step S18 or step S26 (step S22). S30). Here, when the reduction control of the output target value of the B component is performed, the reduction output target value is the reduced output target value Tg × multiplied by rb to the output target value Tg of the G component of the pixel calculated in step S18. When rb is further multiplied by rr, Tg × rb × rr, and when the reduction control of the output target value of the B component is not performed, the output target value Tg of the G component of the pixel is multiplied by rr.

  Since the G component correction process in step S30 is the same as the B component correction process in step S12, detailed description thereof is omitted. That is, in step S30, processing is performed as shown in FIG.

  FIG. 14 is an explanatory diagram of the output target value function of the G component in the first embodiment.

  In FIG. 14, as in FIG. 12, the horizontal axis represents the input pixel value of the G component, the vertical axis represents the output value (measured value, physical quantity) corresponding to the output pixel value of the G component, and the input pixel value at the reference pixel is This represents a change in the output pixel value when given. More specifically, in FIG. 14, the measurement value of the reference pixel is represented by an output target value function T20, and the measurement value of the pixel is represented by a function MG. FIG. 14 shows an example of the output target value of the G component when the reduction control of the output target value of the B component and the R component is performed in step S12. Also for the G component, as a result of being performed at the output target value reduction rate rg, a function T21 in FIG.

  Returning to FIG. Subsequent to step S30, when the reduction control of the G component output target value is performed (step S32: Y), the correction pixel value becomes equal to or less than the maximum pixel value as in step S16. The reduction rate rg of the output target value of the G component at the time is acquired (step S34). Then, the image correction apparatus 200 uses the reduction ratio rg to calculate output target values of the B component and the R component that are other color components of the pixel (step S36).

  Here, when the output target value of the B component calculated in step S36 is different from the output target value used in step S12, or the output target value of the R component calculated in step S36 is the output used in step S20. When it is different from the target value (step S38: Y), the process returns to step S12, and the correction processing of each component is performed again in order from the B component again using the output target value of the B component obtained in step S36.

  The output target value of the B component calculated in step S36 is the same as the output target value used in step S12, and the output target value of the R component calculated in step S36 is the output target value used in step S20. At the same time (step S38: N) or when the reduction control of the output target value of the G component is not performed in step S32 (step S32: N), the image correction apparatus 200 has completed the correction processing for all pixels. Whether or not (step S39).

  When the correction process is completed for all the pixels of the image (step S39: Y), the image correction apparatus 200 ends the series of processes (end), and when the correction process is not completed for all the pixels of the image (end). Step S39: N), the process returns to Step S10.

  As described above, in the first embodiment, the correction pixel value is obtained while reducing the output target value for each color component, and the output target value is updated according to the reduction rate of the output target value. Then, every time the output target value is changed, correction processing is performed in order from the first color component using the changed output target value, so that the output target value of each color component is finally reduced at the same ratio. It is processed like so. The reduction ratio obtained in FIG. 10 is held as a variable indicating the ratio in step S106 in FIG.

  As described above, the image correction apparatus 200 can adjust the correction amount so that the correction pixel value does not exceed the pixel value maximum value for the pixel value of each color component in the RGB color space. Then, the correction amount can be adjusted while the u ′ component and the v ′ component of the pixel in the u′v ′ chromaticity diagram coincide with the u ′ component and the v ′ component of the reference pixel.

  FIG. 15 is an explanatory diagram of processing for converting the pixel value in the RGB space into the u ′ component and the v ′ component of the u′v ′ chromaticity diagram.

  In FIG. 15, it is assumed that the R component pixel value in the RGB space is R, the G component pixel value is G, and the B component pixel value is B, and RGBmax is the maximum pixel value.

  At this time, the pixel value of the pixel in the RGB space can be converted into the pixel value in the XYZ space (CIE 1964 color system) by a series of conversion formulas shown in FIG. Then, the pixel value in the XYZ space can be further converted into the u ′ component and the v ′ component in the u′v ′ chromaticity diagram (CIE 1976 UCS chromaticity diagram) by a series of conversion formulas shown in FIG. 15. In the u′v ′ chromaticity diagram, the hue and saturation are represented by the u ′ component and the v ′ component.

  In the first embodiment, as described above, when the corrected pixel value exceeds the maximum pixel value, the output target value after reduction in which the output target value of each color component in the RGB color space is reduced at the same ratio is used. Therefore, the variables r, g, b, X component, and Y component shown in FIG. 15 are reduced at the same ratio by aligning the corrected pixel value of the pixel with the measurement value of the reference pixel that is the output target value. become. Accordingly, since the u ′ component and the v ′ component can be made constant, the hue and saturation of the pixel can be matched with the hue and saturation of the reference pixel in a range where the corrected pixel value does not exceed the maximum pixel value.

  In addition, since each component is reduced at the same ratio, the correction pixel value for the pixel value of each RGB color component always exceeds the maximum pixel value if correction processing is performed three times at the maximum for each color component of RGB. So that the process can be completed.

  In the above-described embodiment, the measurement value is adopted as the output target value, but the present invention is not limited to this. For example, as the output target value, an average value of pixel values in a predetermined area centered on the reference pixel is adopted, or an output target value is adopted such that the value becomes smaller as the distance from the reference pixel increases. it can.

  Next, step S116 in FIG. 9 will be described.

  In step S116, when the luminance of the output target value cannot be obtained, the luminance of the pixel is complemented by using a plurality of pixels of the remaining projectors (projectors that have not performed the output saturation process). To control.

  In the first embodiment, when complementing the luminance of the display pixel by the first projector PJ1 as the first pixel light forming unit, the first pixel among the plurality of pixel light forming units used for complementing the luminance of the pixel. The remaining at least one pixel light forming unit excluding the light forming unit is a display pixel formed on the screen SCR based on the position of the display pixel formed on the screen SCR by the pixel light from the first pixel light forming unit. It is assumed that n (n is an integer of 2 or more) display pixels are formed in the order of the positions of. Then, it is assumed that the image signal is corrected so that each pixel light constituting the plurality of pixel lights uniformly increases the luminance. Note that n is preferably 4.

  FIG. 16 shows a flowchart of a processing example of step S116 of FIG.

  For example, the ROM 82 stores in advance a program for realizing the processing shown in FIG. 16, and the CPU 80 having the function of the image processing circuit 88 or an image processing circuit 88 including a CPU (not shown) is stored in the ROM 82. The processing shown in FIG. 16 can be realized by software processing by reading the program and executing processing corresponding to the program.

Here, it is assumed that an output target value is generated by performing output saturation processing in the pixel S of the first projector PJ1. The peripheral pixel corresponding to this pixel S is A _pq (p, q = 0 or 1), the output target value of the pixel S is RGBT_S, the output target value of the pixel A _pq is RGBT_A _pq , and the luminance of the output target value of the pixel S is The luminance of the output target value of YT_S and pixel A _pq is YT_A _pq . Further, the reduction ratio of the output target value by the output saturation process of the pixel S is RATE_S, and the reduction ratio of the output target value by the output saturation process of the pixel A _pq is RATE_A _pq .

First, the image correction apparatus 200 calculates the luminance YT_S of the output target value of the pixel S (Step S60). This calculation process may be calculated as the following equation using a general conversion equation for calculating luminance from the RGB space.
YT_S = (0.212671 × RGBT_S.R + 0.715160 × RGBT_S.G + 0.072169 × RGBT_S.B) / RGBMax
Here, for example, if the data of each color component of RGB is 8 bits, the pixel maximum value RGBMax is 255. In addition, RGBT_S. R means the R component pixel value of RGBT_S. G represents the pixel value of the G component of RGBT_S, RGBT_S. B means the pixel value of the B component of RGBT_S.

Next, the image correction apparatus 200 updates the reduction ratio RATE_A _pq of the output target value of the pixel A _pq so that the luminance of the display pixel by the first to L-th projectors PJ1 to PJL does not change (step S62). For example, the brightness of the display pixels obtained by the projectors is integrated to obtain the following equation, and by converting this equation, the updated value of RATE_A _pq can be obtained.

In the above equation, α is obtained so that RATE_A _pq is incremented by the same α and the sum of luminances remains unchanged. Using this α, RATE_A _pq is updated as in the following equation.
RATE_A _pq = RATE_A _pq + α

Subsequently, the image correction apparatus 200 updates the output target value of the pixel A _pq according to the following equation using the RATE_A _pq obtained in step S62 (step S64), and ends the series of processes (end).
RGBT_A _pq = RGBT_A _pq × RATE_A _pq

  By performing the processing as described above, an increase in luminance of the pixel is equally allocated to the peripheral pixels, and the luminance of the pixel by the first projector can be complemented by a plurality of pixels by other projectors.

  FIG. 17 is an explanatory diagram of the effect of the first embodiment. In FIG. 17, the same parts as those in FIG.

  For example, when the four pixels DP2 of the projection image of the second projector PJ2 are displayed as the peripheral pixels of the pixel DP1 of the projection image of the first projector PJ1, the pixels DP1 and DP2 of both projectors perform output saturation processing, respectively. If the brightness of the output target value can be displayed as it is without any change, both projectors display the pixels at the brightness of each output target value.

  On the other hand, as shown in FIG. 17, for example, when output saturation processing is performed in the pixel DP1 of the first projector PJ1 and display cannot be performed with the luminance of the initial output target value, the four projectors PJ2 In the pixel DP2, the output target value is updated and displayed with the luminance uniformly increased, and as a result, the luminance of the pixel is increased.

  18 (A) and 18 (B) show other explanatory diagrams regarding the effects of the first embodiment. 18A and 18B show the pixels DP1 to DP3 by the first to third projectors PJ1 to PJ3.

  As shown in FIG. 18A, the pixels DP1 by the first projector PJ1 are arranged in the horizontal direction, the pixels DP2 by the second projector PJ2 are arranged in the horizontal direction, and the pixels DP3 by the third projector PJ3 are arranged in the horizontal direction. line up. The pixel DP1 group is disposed between the pixel DP2 group and the pixel DP3 group. Thereby, if attention is paid to the pixel DP1, the luminance can be increased by using the pixels DP2 and DP3.

  For example, when the pixel DP1 of the projection image of the first projector PJ1, the pixel DP2 of the projection image of the second projector PJ2, and the pixel DP3 of the projection image of the third projector PJ3 are displayed side by side, the pixels of these projectors When DP1 to DP3 can display the luminance of the output target value as it is without performing the output saturation process, these projectors display pixels at the luminance of each output target value.

  On the other hand, for example, when the output saturation processing is performed in the pixel DP1 of the first projector PJ1 and the display cannot be performed with the luminance of the initial output target value, as shown in FIG. 18B, the second projector PJ2 In the pixel DP2 and the pixel DP3 of the third projector PJ3, the output target value is updated and displayed with the brightness increased. That is, half of the luminance deficiency of the pixel DP1 is complemented by the two pixels DP2. Therefore, each of the two pixels DP2 complements the luminance deficiency 1/4 of the pixel DP1. Similarly, half of the luminance deficiency of the pixel DP1 is complemented by the two pixels DP3. Therefore, each of the two pixels DP3 complements the luminance deficiency ¼ of the pixel DP1.

  FIG. 19A and FIG. 19B show still another explanatory diagram about the effect of the first embodiment. FIGS. 19A and 19B show the pixels DP1 to DP4 by the first to fourth projectors PJ1 to PJ4.

  As shown in FIG. 19A, the pixel DP1 by the first projector PJ1, the pixel DP2 by the second projector PJ2, the pixel DP3 by the third projector PJ3, and the pixel DP4 by the fourth projector are like a checkered pattern. Placed in. Thereby, if attention is paid to the pixel DP1, the luminance can be increased by using the pixels DP2 and DP3. If attention is paid to the pixel DP3, the luminance can be increased by using the pixels DP1 and DP4.

  For example, the pixel DP1 of the projection image of the first projector PJ1, the pixel DP2 of the projection image of the second projector PJ2, the pixel DP3 of the projection image of the third projector PJ3, and the pixel DP4 of the projection image of the fourth projector PJ4. As shown in FIG. 19A, when the pixels DP1 to DP4 of these projectors can display the luminance of the output target value as they are without performing the output saturation process, The pixel is displayed with the brightness of the output target value.

  On the other hand, for example, when the output saturation process is performed in the pixel DP1 of the first projector PJ1 and the display cannot be performed with the luminance of the initial output target value, as shown in FIG. 19B, the second projector PJ2 In the pixel DP2 and the pixel DP3 of the third projector PJ3, the output target value is updated and displayed with the brightness increased. That is, half of the luminance deficiency of the pixel DP1 is complemented by the two pixels DP2. Therefore, each of the two pixels DP2 complements the luminance deficiency 1/4 of the pixel DP1. Similarly, half of the luminance deficiency of the pixel DP1 is complemented by the two pixels DP3. Therefore, each of the two pixels DP3 complements the luminance deficiency ¼ of the pixel DP1.

  As described above, according to the first embodiment, when the luminance of the pixel does not reach the output target value, the luminance is evenly supplemented to the peripheral pixels of the pixel. Can be prevented. In addition, according to the first embodiment, since the luminance increment is uniformly assigned to the peripheral pixels, the effect of preventing the occurrence of luminance unevenness can be obtained with a small amount of calculation while suppressing the decrease in luminance.

[Embodiment 2]
In the first embodiment, when the luminance of the pixel does not reach the output target value, the luminance is uniformly complemented to the peripheral pixels of the pixel. However, the present invention is not limited to this. In the second embodiment according to the present invention, the luminance is increased more as a pixel having a margin of luminance increase among the peripheral pixels of the pixel.

  FIG. 20A and FIG. 20B are explanatory diagrams of luminance complement processing in the second embodiment. 20A, parts similar to those in FIG. 17 are denoted by the same reference numerals, and description thereof is omitted as appropriate. 20A and 20B show that the luminance of the pixel DP1 is complemented by the pixel DP2 around the pixel DP1, but the present invention is not limited to this. Luminance may be complemented with the peripheral pixels shown in FIGS. 18A and 19A.

  In FIG. 20A, four pixels DP2 around the pixel DP1 are shown as pixels DP2-1, DP2-2, DP2-3, and DP2-4, respectively, and FIG. 20B shows pixels DP2-1 to DP2-1. The luminance of DP2-3 and the output target values T-1 to T-4 are schematically represented.

  Here, paying attention to the margins MM-1 to MM-4 of the luminance of the four pixels DP2-1 to DP2-4 and the output target values T-1 to T-4, the margin MM-3 of the pixel DP2-3 is At the maximum, the margin MM-2 of the pixel DP2-2 is the minimum. Therefore, in the second embodiment, when the luminance deficiency of the pixel DP1 is distributed to the pixels DP2-1 to DP2-4 to increase the luminance of the pixels DP2-1 to DP2-4, the luminance increment is increased with respect to the pixel DP2-3. It distributes so that it may become the maximum, and it distributes so that a luminance increment may become the minimum with respect to pixel DP2-2. That is, in the second embodiment, the image signal is corrected so that the luminance increment is larger than the pixel light having the large margin of luminance increase among the plurality of pixel lights, compared to the pixel light having the small margin of luminance increment among the plurality of pixel lights. To do.

  As a result, even if the luminance after increment (correction) exceeds the pixel maximum value in the processing of the first embodiment, the deficiency is efficiently allocated in the processing of the second embodiment, and the luminance after the increment is increased. In some cases, the maximum pixel value may not be exceeded.

  Since the configuration of the image correction apparatus and the image display system that realizes the second embodiment is the same as that of the first embodiment, detailed description of the configuration of the image correction apparatus and the image display system in the second embodiment is omitted. . The difference between the second embodiment and the first embodiment is the processing content of the luminance complement processing.

  Therefore, the luminance complementing process in the second embodiment will be described below. In the second embodiment, the margin of each peripheral pixel may be calculated as described above, and processing may be performed so as to allocate a luminance deficiency according to the margin, but the processing is simplified as follows. Also good. In other words, on the assumption that the output target value does not change so much between neighboring pixels, the pixel group that has not been subjected to the output saturation process is distributed so as to have the same luminance, so that the pixel group that has undergone the output saturation process is distributed. The luminance increment margin can be increased as the luminance is reduced and the luminance is lower.

  FIG. 21 shows a flowchart of a processing example of luminance complement processing in the second embodiment. In the second embodiment, the process of FIG. 21 is performed in step S116 of FIG. 9 in the first embodiment.

  For example, the ROM 82 stores a program for realizing the processing shown in FIG. 21 in advance, and the CPU 80 having the image processing circuit 88 or the image processing circuit 88 including a CPU (not shown) stores the program stored in the ROM 82. The processing shown in FIG. 21 can be realized by software processing by reading and executing processing corresponding to the program.

Here, it is assumed that an output target value is generated by performing output saturation processing in the pixel S of the first projector PJ1. The peripheral pixel corresponding to this pixel S is A _pq (p, q = 0 or 1), the output target value of the pixel S is RGBT_S, the output target value of the pixel A _pq is RGBT_A _pq , and the luminance of the output target value of the pixel S is The luminance of the output target value of YT_S and pixel A _pq is YT_A _pq . Among the peripheral pixels, pixels that have not been subjected to output saturation processing (pixels of RATE_A _{00 to} RATE_A ₁₁ = 1.0) are pixels AN0 to ANh (h is a maximum of “3”), and pixels that have undergone output saturation processing. Assume that (RATE_A _{00 to} RATE_A ₁₁ <1.0 pixel) are AS0 to ASk (h + k = 2), and the pixels AN0 to ANh have the same luminance YTN. Further, the reduction ratio of the output target value by the output saturation process of the pixel S is RATE_S, the reduction ratio of the output target value by the output saturation process of the pixel AN _j (j is an integer from 0 to h), the RATE_AN _j , and the pixel AN. luminance YT_AN _j output target value of _j, the pixel _AS r (r is an integer, j + r = 2) of RATE_AS _r a reduction ratio of the output target value by the output saturation, luminance YT_AS _r output target value of the pixel AS _r And

First, the image correction apparatus calculates the luminance YT_S of the output target value of the pixel S (Step S70). This calculation process may be calculated as the following equation using a general conversion equation for calculating luminance from the RGB space.
YT_S = (0.212671 × RGBT_S.R + 0.715160 × RGBT_S.G + 0.072169 × RGBT_S.B) / RGBMax
Here, for example, if the data of each color component of RGB is 8 bits, the pixel maximum value RGBMax is 255. In addition, RGBT_S. R means the R component pixel value of RGBT_S. G represents the pixel value of the G component of RGBT_S, RGBT_S. B means the pixel value of the B component of RGBT_S.

  Next, the image correction apparatus calculates the luminance YTN so that the pixels not subjected to the output saturation processing have the same luminance YTN so that the luminance of the display pixels by the first to L-th projectors PJ1 to PJL does not change. (Step S72).

Subsequently, the image correction apparatus updates the output target value of the pixel AN _j (j is an integer of 0 to h) according to the following equation using the YTN obtained in step S72 (step S74), End processing (END).
RGBT_AN _j = RGBT_AN _j × YTN / YT_AN _j

Here, RGBT_AN _j is RGBT_A _{pq of the} pixel A _pq corresponding to the pixel AN _j , and YT_AN _j is the luminance YT_A _pq of the pixel A _pq corresponding to the pixel AN _j .

  By performing the processing as described above, the luminance deficiency of the pixel can be allocated to a pixel having a smaller luminance among the peripheral pixels. Can be allocated so that the luminance increment is larger than that of a pixel having a small margin.

[Embodiment 3]
In the first embodiment or the second embodiment, the shortage of the luminance of the pixel is allocated to the peripheral pixel without holding the luminance ratio of the peripheral pixel. However, the present invention is not limited to this. In the third embodiment according to the present invention, the luminance deficiency is allocated to the peripheral pixels of the pixel while maintaining the luminance ratio of the peripheral pixels.

  FIG. 22A and FIG. 22B are explanatory diagrams of luminance complement processing in the third embodiment. 22A, parts similar to those in FIG. 20A are denoted by the same reference numerals, and description thereof is omitted as appropriate. In FIGS. 22A and 22B, the luminance of the pixel DP1 is shown to be complemented by the pixel DP2 around the pixel DP1, but the present invention is not limited to this. Luminance may be complemented with the peripheral pixels shown in FIGS. 18A and 19A.

  In FIG. 22A, four pixels DP2 around the pixel DP1 are shown as pixels DP2-1, DP2-2, DP2-3, and DP2-4, respectively, and FIG. 22B shows pixels DP2-1 to DP2-1. The luminance of DP2-4 is schematically represented.

  In the third embodiment, when the pixels DP2-1 to DP2-4 have luminance as shown in FIG. 22B, the luminance of the two pixels DP2-1 and DP2-2 before correction and the two pixels DP2-3, The luminance deficiency of the pixel DP1 is allocated to the four pixels DP2-1 to DP2-4 so that the ratio with the luminance of DP2-4 is constant. That is, in the third embodiment, since the luminance corresponds to the pixel value, the image is set so as to increase with respect to each pixel light constituting the plurality of pixel lights according to the pixel value corresponding to the luminance of each pixel light. The signal is corrected.

  Thereby, in the processing of the third embodiment, it is possible to prevent the occurrence of luminance unevenness while maintaining the luminance distribution before correction and suppressing the decrease in luminance.

  Since the configuration of the image correction apparatus and the image display system that realizes the third embodiment is the same as that of the first embodiment, a detailed description of the configuration of the image correction apparatus and the image display system in the third embodiment is omitted. . The difference between the third embodiment and the first embodiment is the processing content of the luminance complement processing. Therefore, the luminance complementing process in the third embodiment will be described below.

  FIG. 23 shows a flowchart of a processing example of luminance complement processing in the third embodiment. In the third embodiment, the process of FIG. 23 is performed in step S116 of FIG. 9 in the first embodiment.

  For example, a program for realizing the processing shown in FIG. 23 is stored in the ROM 82 in advance, and the CPU 80 having the function of the image processing circuit 88 or an image processing circuit 88 including a CPU (not shown) is stored in the ROM 82. The processing shown in FIG. 23 can be realized by software processing by reading the program and executing processing corresponding to the program.

Here, it is assumed that an output target value is generated by performing output saturation processing in the pixel S of the first projector PJ1. The peripheral pixel corresponding to this pixel S is A _pq (p, q = 0 or 1), the output target value of the pixel S is RGBT_S, the output target value of the pixel A _pq is RGBT_A _pq , and the luminance of the output target value of the pixel S is The luminance of the output target value of YT_S and pixel A _pq is YT_A _pq . Among the peripheral pixels, pixels that have not been subjected to output saturation processing (pixels of RATE_A _{00 to} RATE_A ₁₁ = 1.0) are pixels AN0 to ANh (h is a maximum of “3”), and pixels that have undergone output saturation processing. Let (RATE_A _{00 to} RATE_A ₁₁ <1.0 pixels) be AS0 to ASk (h + k = 2). Further, the reduction ratio of the output target value by the output saturation process of the pixel S is RATE_S, the reduction ratio of the output target value by the output saturation process of the pixel AN _j (j is an integer from 0 to h), the RATE_AN _j , and the pixel AN. luminance YT_AN _j output target value of _j, the pixel _AS r (r is an integer, j + r = 2) of RATE_AS _r a reduction ratio of the output target value by the output saturation, luminance YT_AS _r output target value of the pixel AS _r And

First, the image correction apparatus calculates the luminance YT_S of the output target value of the pixel S (Step S80). This calculation process may be calculated as the following equation using a general conversion equation for calculating luminance from the RGB space.
YT_S = (0.212671 × RGBT_S.R + 0.715160 × RGBT_S.G + 0.072169 × RGBT_S.B) / RGBMax
Here, for example, if the data of each color component of RGB is 8 bits, the pixel maximum value RGBMax is 255. In addition, RGBT_S. R means the R component pixel value of RGBT_S. G, RGBT_S. The same applies to B.

Next, the image correction device, so that the luminance of the display pixels by the projector PJ1~PJL of the first to L does not change, pixel _AN j that does not output saturation (j is any integer 0～H) The brightness YT_AN _j is multiplied by the same ratio (step S82).

Subsequently, the image correction apparatus updates the output target value of the pixel AN _j (j is an integer from 0 to h) according to the following equation using α obtained in step S82 (step S84). End processing (END).
RATE_AN _j = α
RGBT_AN _j = RGBT_AN _j × RATE_AN _j

Here, RGBT_AN _j is RGBT_A _pq of the pixel A _pq corresponding to the pixel AN _j .

  By performing the processing as described above, it becomes possible to allocate a shortage of luminance of the pixel to the peripheral pixel while maintaining the luminance ratio before correction of the peripheral pixel.

[Embodiment 4]
In the first to third embodiments, the shortage of luminance of the pixel is assigned to the peripheral pixel regardless of the distance between the pixel and the peripheral pixel. However, the present invention is not limited to this. In Embodiment 4 according to the present invention, an insufficient amount of luminance of the pixel is allocated according to the distance between the pixel and the peripheral pixel.

  FIG. 24 is an explanatory diagram of luminance complement processing in the fourth embodiment. 24, the same portions as those in FIG. 20A are denoted by the same reference numerals, and description thereof will be omitted as appropriate. Note that in FIG. 24, the luminance of the pixel DP1 is shown to be complemented by the pixel DP2 around the pixel DP1, but the present invention is not limited to this, and FIG. 18 (A) and FIG. Luminance may be complemented by the peripheral pixels shown in A). In FIG. 24, the four pixels DP2 around the pixel DP1 are shown as pixels DP2-1, DP2-2, DP2-3, and DP2-4, respectively.

  In the fourth embodiment, the insufficient luminance of the pixel DP1 is allocated to the four pixels DP2-1 to DP2-4 according to the distance between the pixel DP1 and each of the pixels DP2-1 to DP2-4. That is, in Embodiment 4, for each pixel light constituting a plurality of pixel lights, each pixel light is based on the position of the display pixel DP1 formed on the screen SCR by the pixel light from the first pixel light forming means. Thus, the image signal is corrected so as to increase in accordance with the distance to the display pixel formed on the screen SCR.

  Thereby, in the process of the fourth embodiment, even when the alignment of the display pixels of each projector is roughly adjusted, the luminance unevenness is suppressed with the same accuracy as the first to third embodiments while suppressing the decrease in the luminance. Occurrence can be prevented.

  Since the configuration of the image correction apparatus and the image display system that implements the fourth embodiment is the same as that of the first embodiment, detailed description of the configuration of the image correction apparatus and the image display system in the fourth embodiment is omitted. . The difference between the fourth embodiment and the first embodiment is the processing content of the luminance complement processing. Therefore, the luminance complementing process in the fourth embodiment will be described below.

  FIG. 25 shows a flowchart of a processing example of luminance complement processing in the fourth embodiment. In the fourth embodiment, the process of FIG. 25 is performed in step S116 of FIG. 9 in the first embodiment.

  For example, the ROM 82 stores in advance a program for realizing the processing shown in FIG. 25, and the CPU 80 having the function of the image processing circuit 88 or an image processing circuit 88 including a CPU (not shown) is stored in the ROM 82. The processing shown in FIG. 25 can be realized by software processing by reading the program and executing processing corresponding to the program.

Here, it is assumed that an output target value is generated by performing output saturation processing in the pixel S of the first projector PJ1. The peripheral pixel corresponding to this pixel S is A _pq (p, q = 0 or 1), the output target value of the pixel S is RGBT_S, the output target value of the pixel A _pq is RGBT_A _pq , and the luminance of the output target value of the pixel S is The luminance of the output target value of YT_S and pixel A _pq is YT_A _pq . Among the peripheral pixels, pixels that have not been subjected to output saturation processing (pixels of RATE_A _{00 to} RATE_A ₁₁ = 1.0) are pixels AN0 to ANh (h is a maximum of “3”), and pixels that have undergone output saturation processing. Let (RATE_A _{00 to} RATE_A ₁₁ <1.0 pixels) be AS0 to ASk (h + k = 2). Further, the reduction ratio of the output target value by the output saturation process of the pixel S is RATE_S, the reduction ratio of the output target value by the output saturation process of the pixel AN _j (j is an integer from 0 to h), the RATE_AN _j , and the pixel AN. luminance YT_AN _j output target value of _j, the pixel _AS r (r is an integer, j + r = 2) of RATE_AS _r a reduction ratio of the output target value by the output saturation, luminance YT_AS _r output target value of the pixel AS _r And

First, the image correction apparatus calculates the luminance YT_S of the output target value of the pixel S (Step S90). This calculation process may be calculated as the following equation using a general conversion equation for calculating luminance from the RGB space.
YT_S = (0.212671 × RGBT_S.R + 0.715160 × RGBT_S.G + 0.072169 × RGBT_S.B) / RGBMax
Here, for example, if the data of each color component of RGB is 8 bits, the pixel maximum value RGBMax is 255. In addition, RGBT_S. R means the R component pixel value of RGBT_S. G, RGBT_S. The same applies to B.

  Next, the image correction apparatus calculates the distance between the pixel S and each peripheral pixel (step S92). This distance is the distance between the bright spot of the image formed by the pixel light forming the pixel S and the bright spot of the image formed by the pixel light forming the peripheral pixels, and prior to the processing of FIG. It may be sought.

Next, the image correction device, so that the luminance of the display pixels by the projector PJ1~PJL of the first to L does not change, pixel _AN j that does not output saturation (j is any integer 0～H) the luminance YT_AN _j, multiplying the ratio is inversely proportional to the distance _{L j} (step S94).

Subsequently, the image correction apparatus updates the output target value of the pixel AN _j (j is an integer from 0 to h) according to the following equation using α obtained in step S94 (step S84). End processing (END).
RATE_AN _j = α / L _j
RGBT_AN _j = RGBT_AN _j × RATE_AN _j

Here, RGBT_AN _j is RGBT_A _pq of the pixel A _pq corresponding to the pixel AN _j .

  By performing the processing as described above, an insufficient amount of luminance of the pixel can be allocated to the peripheral pixel according to the distance between the pixel and the peripheral pixel.

[Embodiment 5]
In the first to fourth embodiments, each projector is described as projecting the pixel light formed by the pixel light forming unit onto the screen. However, the present invention is not limited to this. In Embodiment 5 according to the present invention, one projector has one projection unit, and pixel light formed by a plurality of pixel light forming units is incident on the projection unit.

  FIG. 26 shows a configuration example of the projector in the fifth embodiment. For example, at least one of the first to Lth projectors PJ1 to PJL in FIG. 1 may have the configuration of FIG.

  The projector 800 according to the fifth embodiment includes an illumination device 810 that emits light including R component color light (first color light), G component color light (second color light), and B component color light (third color light). , A polarization separation mirror 820 as a polarization separation optical system, a first pixel light formation unit 900 as a first pixel light formation unit that emits first pixel light, and a second that emits second pixel light. The second pixel light forming unit 950 as the pixel light forming means, the polarization combining prism 850 (light combining means) as the polarization combining optical system, and the projection for projecting the pixel light combined by the polarization combining prism 850 onto the screen SCR. An optical system 860. The projection optical system 860 in FIG. 3 has a function equivalent to that of the projection lens 170 in FIG.

  The illuminating device 810 includes a light source device (including an unillustrated arc tube, an elliptical reflector, a concave lens, and the like) 811 that emits an illuminating beam toward the illuminated region side, and an illuminating beam that is emitted from the light source device 811 into a plurality of partial beams. A first lenslet array 812 having a first lenslet for splitting, and a second lenslet having a plurality of second lenslets corresponding to the plurality of first lenslets of the first lenslet array 812. A small lens array 813 and a superimposing lens 814 for superimposing the partial light beams emitted from the second small lens array 813 in the illuminated area.

  The polarization separation mirror 820 has a function of separating light from the illumination device 810 into light having a first polarization component (for example, p-polarization) and light having a second polarization component (for example, s-polarization).

  The first pixel light forming unit 900 includes a first color separation optical system 910 that separates light having the first polarization component separated by the polarization separation mirror 820 into R component, G component, and B component color light, A first light modulation element 920R, a second light modulation element 920G, a third light modulation element 920B for modulating each color light separated by the first color separation optical system 910, and these first light modulation elements Cross dichroic as a first color synthesis optical system for synthesizing R component color light, G component color light and B component color light respectively modulated by 920R, second light modulation element 920G, and third light modulation element 920B And a prism 940. The first light modulation element 920R has the same function as the R liquid crystal panel 130R of FIG. The second light modulation element 920G has the same function as the G liquid crystal panel 130G in FIG. The third light modulation element 920B has the same function as the B liquid crystal panel 130B of FIG.

  The cross dichroic prism 940 includes R component color light, G component color light, and B component modulated by the first light modulation element 920R, the second light modulation element 920G, and the third light modulation element 920B, respectively. It has a first color light incident surface 940R, a second color light incident surface 940G, and a third color light incident surface 940B on which the component color light is incident.

  The first pixel light forming unit 900 configured as described above emits the first pixel light having the first polarization component, and the first pixel light is the first pixel light of the polarization combining prism 850. Incident on the incident surface 851.

  The first color separation optical system 910 includes a first dichroic mirror 911 that separates light having the first polarization component separated by the polarization separation mirror 820 into R component color light and other component color light, and A second dichroic mirror 912 that separates the color light of the other component separated by one dichroic mirror 911 into color light of G component and color light of B component, a reflection mirror 913, and a relay optical system 930 are included.

  The R component color light reflected by the first dichroic mirror 911 is bent by the reflection mirror 913 and enters the pixel formation region of the liquid crystal panel of the first light modulation element 920R. In addition, the G component color light out of the G component and the B component that has passed through the first dichroic mirror 911 is reflected by the second dichroic mirror 912 and enters the pixel formation region of the liquid crystal panel of the second light modulation element 920G. To do. On the other hand, the B component color light passes through the second dichroic mirror 912 and enters the relay optical system 930.

  The relay optical system 930 includes an incident-side lens 931, an incident-side reflection mirror 932, a relay lens 933, and an emission-side reflection mirror 934, and transmits the B component color light transmitted through the second dichroic mirror 912. It has a function of leading to the liquid crystal panel of the third light modulation element 920B.

  The first light modulation element 920R, the second light modulation element 920G, and the third light modulation element 920B modulate the illumination light beam according to the image signal, and are the illumination target of the illumination device 810. Each of the first light modulation element 920R, the second light modulation element 920G, and the third light modulation element 920B includes a liquid crystal panel, an incident-side polarizing plate disposed on the light incident side of the liquid crystal panel, and the liquid crystal panel And an exit-side polarizing plate disposed on the light exit side. Note that the reference numerals of the liquid crystal panel, the incident-side polarizing plate, and the emission-side polarizing plate are omitted in FIG.

  The cross dichroic prism 940 is an optical element that forms a color image by combining optical images modulated for the respective color lights incident on the first to third color light incident surfaces 940R, 940G, and 940B. The cross dichroic prism 940 has a substantially square shape in plan view in which four right-angle prisms are bonded together, and a dielectric multilayer film is formed on a substantially X-shaped interface in which the right-angle prisms are bonded together. The dielectric multilayer film formed at one interface that is substantially X-shaped reflects the R component color light, and the dielectric multilayer film formed at the other interface reflects the B component color light. It is. The color light of the R component and the B component is bent by these dielectric multilayer films, and the three color lights are synthesized by aligning with the traveling direction of the color light of the G component.

  The second pixel light forming unit 950 includes a second color separation optical system 960 that separates light having the second polarization component separated by the polarization separation mirror 820 into R component, G component, and B component color light, and A fourth light modulation element 970R, a fifth light modulation element 970G, and a sixth light modulation element 970B for modulating each color light separated by the second color separation optical system 960, and the fourth light modulation element 970R. Cross dichroic prism as a second color synthesis optical system for synthesizing R component color light, G component color light and B component color light respectively modulated by the fifth light modulation element 970G and the sixth light modulation element 970B 990.

  Note that the cross dichroic prism 990 includes R component color light, G component color light, and B component modulated by the fourth light modulation element 970R, the fifth light modulation element 970G, and the sixth light modulation element 970B, respectively. It has a first color light incident surface 990R, a second color light incident surface 990G, and a third color light incident surface 990B on which the component color light is incident.

  The second pixel light forming unit 950 configured as described above emits second pixel light having a second polarization component, and the second pixel light is the second pixel light of the polarization combining prism 850. Incident on the incident surface 852.

  The second color separation optical system 960 includes a third dichroic mirror 961 that separates the light having the second polarization component separated by the polarization separation mirror 820 into R component color light and other component color light. A fourth dichroic mirror 962, a reflection mirror 963, and a relay optical system 980 that separates the color light of the other components separated by the dichroic mirror 961 into the color light of the G component and the color light of the B component.

  The B component color light reflected by the third dichroic mirror 961 is bent by the reflection mirror 963 and enters the pixel formation region of the liquid crystal panel of the sixth light modulation element 970B. In addition, the G component color light out of the G component and R component that has passed through the third dichroic mirror 961 is reflected by the fourth dichroic mirror 962 and is incident on the pixel formation region of the liquid crystal panel of the fifth light modulation element 970G. To do. On the other hand, the R component color light passes through the fourth dichroic mirror 962 and enters the relay optical system 980.

  The relay optical system 980 includes an incident side lens 981, an incident side reflection mirror 982, a relay lens 983, and an emission side reflection mirror 984. The relay optical system 980 transmits R component color light transmitted through the fourth dichroic mirror 962. It has a function of leading to the liquid crystal panel of the fourth light modulation element 970B.

  The fourth light modulation element 970R, the fifth light modulation element 970G, and the sixth light modulation element 970B are the first light modulation element 920R, the second light modulation element 920G, and the third light modulation element 920B. Since the cross dichroic prism 990 has the same configuration as the cross dichroic prism 940, detailed description thereof will be omitted.

  The polarization combining prism 850 includes a first pixel light incident surface 851 on which the first pixel light emitted from the first pixel light forming unit 900 is incident, and a second pixel light emitted from the second pixel light forming unit 950. A second pixel light incident surface 852 on which the first pixel light is incident and a polarization combining surface that combines the light having the first polarization component and the light having the second polarization component. . Then, the first pixel light incident on the first pixel light incident surface 851 and the second pixel light incident on the second pixel light incident surface 852 are combined and emitted to the projection optical system 860. The

  The color image emitted from the polarization combining prism 850 is enlarged and projected by the projection optical system 860 to form an image on the screen SCR.

  In the configuration as described above, for example, each light modulation element of the first pixel light formation unit 900 is controlled by an image signal for the first projector PJ1, and each light modulation element of the second pixel light formation unit 950 is controlled by the first signal. The image signals for the projector PJ2 of No. 2 may be controlled, and these image signals may be generated by any of the image correction apparatuses according to the first to third embodiments. As described above, according to the fifth embodiment, the image correction apparatus according to any one of the first to fourth embodiments and the formation of a plurality of pixel lights whose modulation rates are controlled based on the image signal from the image correction apparatus. It is possible to provide an image display system including means and light combining means for combining pixel light from a plurality of pixel light forming means.

  As described above, the image correction apparatus, the image display system, and the image correction method according to the present invention have been described based on the above embodiments, but the present invention is not limited to the above embodiments, and departs from the gist thereof. The present invention can be implemented in various modes as long as it is not, for example, the following modifications are possible.

  (1) In the above embodiment, when determining the output target value, the center pixel of the image is adopted as the reference pixel, but the present invention is not limited to this. For example, a pixel having the highest luminance in the screen may be adopted as the reference pixel. By using the pixel having the highest luminance in the screen as the reference pixel, it is possible to more reliably avoid a decrease in contrast due to correction, compared to the case where the center pixel is the reference pixel.

  (2) In the above embodiment, when the output target value is determined, when the correction pixel value of each color component in the RGB space exceeds the maximum pixel value, processing is performed in the order of the B component, the R component, and the G component. However, the present invention is not limited to the order of processing color components.

  (3) In the above embodiment, the measurement value table has been described on the assumption that the measurement value of each pixel value is stored for all the pixels of the image, but the present invention is not limited to this. For example, in a measurement value table, only measurement values of a predetermined pixel value are stored discretely for a predetermined pixel, and measurement values of pixels not stored in the measurement value table are stored as measurement values stored in the measurement value table. You may make it obtain | require by the well-known data interpolation method used. In this case, the effect of reducing the storage capacity of the measurement value table can be obtained.

  (4) In the above embodiment, the projector has been described as an example, but the present invention is not limited to this. For example, the image display device according to the present invention can be applied to all types of devices that perform image display, such as liquid crystal display devices, plasma display devices, and organic EL display devices.

  (5) In the above embodiment, the image correction apparatus is provided outside the image display apparatus. However, the image correction apparatus may be incorporated in any of a plurality of image display apparatuses constituting the image display system.

  (6) In the above embodiment, the light valve is used as the light modulation element (light modulation unit), but the present invention is not limited to this. For example, DLP (Digital Light Processing) (registered trademark), LCOS (Liquid Crystal On Silicon), or the like may be employed as the light modulation element (light modulation unit).

  (7) In the above embodiment, the present invention has been described as an image correction apparatus, an image display system, and an image correction method. However, the present invention is not limited to this. For example, it may be a program in which processing procedures of an image correction method for realizing the present invention are described, or a recording medium on which the program is recorded.

1 is a block diagram of a configuration example of an image display system in Embodiment 1. FIG. FIG. 2 is a block diagram of a configuration example of an image display device applied to each projector in FIG. 1. The figure which shows the structural example of the 1st projector of FIG. FIG. 3 is a schematic diagram illustrating an example of pixels of a display image on a screen according to the first embodiment. 1 is a block diagram of a configuration example of an image correction apparatus according to Embodiment 1. FIG. Explanatory drawing of the pixel position of the image from which the measured value stored in the measured value table of FIG. 5 is measured. Explanatory drawing of the measured value stored in the measured value table of FIG. FIG. 2 is a block diagram of a hardware configuration example of the image correction apparatus according to the first embodiment. FIG. 3 is a flowchart of a processing example of the image correction apparatus according to the first embodiment. The flowchart of the process example of the determination process of the output target value of FIG. FIG. 11 is a flowchart of a processing example of correction processing for each color component in FIG. 10. Explanatory drawing of the output target value function of B component in Embodiment 1. FIG. FIG. 4 is an explanatory diagram of an output target value function of an R component in the first embodiment. Explanatory drawing of the output target value function of G component in Embodiment 1. FIG. Explanatory drawing of the process which converts into a u 'component and v' component of a u'v 'chromaticity diagram from the pixel value of RGB space. FIG. 10 is a flowchart of a processing example of step S116 in FIG. 9. Explanatory drawing of the effect of Embodiment 1. FIG. FIG. 18A and FIG. 18B are other explanatory diagrams regarding the effects of the first embodiment. FIG. 19A and FIG. 19B are still other explanatory views about the effect of the first embodiment. FIG. 20A and FIG. 20B are explanatory diagrams of luminance complement processing in the second embodiment. FIG. 10 is a flowchart of a processing example of luminance complement processing in the second embodiment. FIG. 22A and FIG. 22B are explanatory diagrams of luminance complement processing in the third embodiment. FIG. 10 is a flowchart of a processing example of luminance complement processing in the third embodiment. Explanatory drawing of the brightness | luminance complementation process in Embodiment 4. FIG. FIG. 10 is a flowchart of a processing example of luminance complement processing in the fourth embodiment. FIG. 10 is a diagram illustrating a configuration example of a projector according to a fifth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Image display system 24 ... Light modulation part 26 ... Projection part 30 ... Image measuring device,
32 ... Camera, 34 ... Measurement value processing unit, 40 ... Image input unit, 42 ... Scanner,
44 ... Digital camera, 46 ... PC, 80 ... CPU, 82 ... ROM,
84 ... RAM, 86 ... I / F circuit, 88 ... Image processing circuit, 90 ... Bus,
200 ... an image correction device, 210 ... an output target value generation unit, 220 ... an image signal output unit,
222... Output saturation processing detection unit, 224... Output target value update unit,
226 ... Correction signal output unit, 230 ... Measurement value table,
PJ1 to PJL ... 1st to Lth projectors, SCR ... screen

Claims (8)

An image correction apparatus that corrects an image formed by display pixels using pixel light from a plurality of pixel light forming means,
An output target value generating unit that generates an output target value corresponding to an input image signal with respect to the first pixel light forming unit constituting the plurality of pixel light forming units;
The brightness of the plurality of pixel lights from the remaining pixel light forming means other than the first pixel light forming means among the plurality of pixel light forming means is adjusted so that the brightness value of the display pixel becomes the output target value. An image correction apparatus comprising: an image signal output unit that corrects an image signal for each pixel light forming unit to be controlled and outputs the image signal to each pixel light forming unit constituting the remaining pixel light forming unit. In claim 1,
The remaining pixel light forming means includes:
With reference to the position of the display pixel formed on the screen by the pixel light from the first pixel light forming means, n (n is an integer of 2 or more) in order from the position of the display pixel formed on the screen. An image correction apparatus that forms display pixels. In claim 1 or 2,
The image signal output unit includes:
An image correction apparatus that corrects the image signal so that each pixel light constituting the plurality of pixel lights uniformly increases in luminance. In claim 1 or 2,
The image signal output unit includes:
The image signal is corrected so that a luminance increment is larger than a pixel light having a small luminance increment margin among the plurality of pixel lights with respect to a pixel light having a large luminance increment margin among the plurality of pixel lights. An image correction apparatus. In claim 1 or 2,
The image signal output unit includes:
An image correction apparatus that corrects the image signal so as to be incremented according to a pixel value corresponding to a luminance of each pixel light with respect to each pixel light constituting the plurality of pixel lights. In claim 1 or 2,
The image signal output unit includes:
For each pixel light constituting the plurality of pixel lights, the pixel light is formed on the screen by the pixel light on the basis of the position of the display pixel formed on the screen by the pixel light from the first pixel light forming means. An image correction apparatus that corrects the image signal so as to increase in accordance with a distance to a display pixel. An image correction apparatus according to any one of claims 1 to 6,
A plurality of pixel light forming means whose luminance is controlled based on the image signal from the image correction device,
An image display system for displaying an image using pixel light from the plurality of pixel light forming means. An image correction method for correcting an image formed by display pixels using pixel light from a plurality of pixel light forming means,
An output target value generating step for generating an output target value corresponding to an input image signal for the first pixel light forming means constituting the plurality of pixel light forming means;
The brightness of the plurality of pixel lights from the remaining pixel light forming means other than the first pixel light forming means among the plurality of pixel light forming means is adjusted so that the brightness value of the display pixel becomes the output target value. An image signal output step of correcting an image signal for each pixel light forming unit to be controlled and outputting the corrected image signal to each pixel light forming unit constituting the remaining pixel light forming unit.