JP2008160441A - Projection device - Google Patents

Abstract

To provide a projection device with little image color shift.
In a projection device 1, a light source unit 2 that emits light of each wavelength of RGB, a detection unit 5 that detects light for each stimulus value of an XYZ color system, and a detection result of the detection unit 5 There is provided a control unit 6 that controls the light emitting elements of the light source unit 2 by converting the intensity of each stimulus value of the XYZ color system into the intensity of each RGB light emitted from the light source unit 2. The light source unit 2 is provided with a red LED 21R, a green LED 21G, and a blue LED 21B, and the detection unit 5 is provided with an X1 sensor, an X2 sensor, a Y sensor, and a Z sensor. The X1 sensor detects a portion including a peak on the short wavelength side of the stimulus value X, and the X2 sensor detects a portion including a peak on the long wavelength side.
[Selection] Figure 1

Description

  The present invention relates to a projection apparatus, and more particularly to a projection apparatus in which a light source unit includes RGB light emitting elements.

  Conventionally, a projection apparatus (projector) that projects and displays an image on a screen has been developed. Such a projection apparatus has an advantage that a large screen can be displayed by a small apparatus, and is excellent in terms of transportability, installation space, and apparatus cost. In a conventional projection apparatus, a method is generally used in which a discharge lamp is used as a light source, and light emitted from the discharge lamp is transmitted through a liquid crystal panel to add an image (see, for example, Patent Document 1).

  In recent years, an LED (Light Emitting Diode) is used as a light source of a projection apparatus. By using an LED instead of a discharge lamp, it is possible to produce a projection device that is smaller, more portable, and consumes less power.

  However, since the oscillation wavelength of the LED has temperature dependence, when the temperature rises as the LED is used, the color and brightness of the emitted light change. For this reason, when the LED is used as the light source of the projection apparatus, there is a problem that the image is color-shifted depending on the projection time, the environmental temperature, and the like.

JP-A-6-317777

  An object of the present invention is to provide a projection device with little image color misregistration.

  According to an aspect of the present invention, a light source unit, an image adding unit that adds an image to the light emitted from the light source unit, a projection optical unit that projects the light with the image added, and the light source unit A detection unit that detects the detected light, and a control unit that controls the light source unit based on a detection result of the detection unit, wherein the light source unit emits red light and green light. And a blue light-emitting element that emits blue light, and the detection unit detects a portion including a peak on the short wavelength side of the stimulus value X of the XYZ color system. A sensor, an X2 sensor that detects a portion of the stimulus value X of the XYZ color system that includes a peak on the long wavelength side, a Y sensor that detects a stimulus value Y of the XYZ color system, and a stimulus value of the XYZ color system And a Z sensor for detecting Z. There is provided.

  According to the present invention, it is possible to realize a projection apparatus with little image color misregistration.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a projection apparatus according to this embodiment.
FIG. 2 is a side view illustrating the image adding unit in the present embodiment.
FIG. 3 is a perspective view illustrating a light receiving member in the present embodiment.
FIG. 4 is a graph illustrating the color matching function of the XYZ display system, the wavelength sensitivity characteristics of each sensor, and the light emission characteristics of each LED, with the horizontal axis representing wavelength and the vertical axis representing intensity and sensitivity.

  As shown in FIG. 1, in the projection apparatus 1 according to the present embodiment, a light source unit 2 that emits light is provided. Further, an image adding unit 3 that adds an image to the light emitted from the light source unit 2 is provided. Further, there is provided a projection optical unit 4 that emits the light with the image added by the image adding unit 3 toward the outside of the projection apparatus 1 and projects the image. Furthermore, a detection unit 5 that detects light emitted from the light source unit 2 is provided. Furthermore, the control part 6 which controls the light source part 2 based on the detection result of the detection part 5 is provided. The projection apparatus 1 is a front projection type projector.

  The light source unit 2 is provided with a red light emitting element that emits red light, a green light emitting element that emits green light, and a blue light emitting element that emits blue light. That is, the light source unit 2 emits light of each wavelength of RGB. On the other hand, the detection unit 5 includes an X1 sensor that detects a portion including a peak on the short wavelength side of the stimulus value X in the XYZ color system, and an X2 that detects a portion including a peak on the long wavelength side of the stimulus value X. A sensor, a Y sensor that detects the stimulus value Y, and a Z sensor that detects the stimulus value Z are provided. That is, the detection unit 5 detects light for each stimulus value in the XYZ color system. And the control part 6 converts the intensity | strength obtained for every stimulus value of the XYZ color system by the detection part 5 into the intensity | strength corresponding to each light emitting element of RGB, and controls the light source part 2. FIG.

Hereinafter, a specific configuration example of each unit will be described.
In the light source unit 2, a red LED 21R as a red light emitting element, a green LED 21G as a green light emitting element, and a blue LED 21B as a blue light emitting element are provided. A collimator 22R that collimates the light emitted from the red LED 21R is provided on the light emitting side of the red LED 21R. Similarly, a collimator 22G and a collimator 22B for collimating these emitted lights are provided on the light emitting sides of the green LED 21G and the blue LED 21B, respectively.

  In addition, one dichroic prism 23 is provided at a position where light emitted from each LED and collimated by each collimator gathers. Inside the dichroic prism 23, a red light reflecting multilayer film mirror 24 that reflects red light and transmits green and blue light, and blue light reflection that reflects blue light and transmits green and red light. The multilayer mirror 25 is provided so as to cross each other. One surface of the dichroic prism 23 is a light exit surface 26.

  The light incident on the dichroic prism 23 from the red LED 21R via the collimator 22R is reflected by the red light reflecting multilayer film mirror 24 and is emitted from the light emitting surface 26. Further, the light incident on the dichroic prism 23 from the green LED 21G via the collimator 22G is linearly transmitted through the dichroic prism 23 and is emitted from the light emitting surface 26. Further, the light incident on the dichroic prism 23 from the blue LED 21B via the collimator 22B is reflected by the blue light reflecting multilayer film mirror 25 and is emitted from the light emitting surface 26.

  Further, a homogenizing optical system 27 for uniformizing the light emitted from the light emitting surface 26 is provided on the light emitting surface 26 side of the dichroic prism 23. The homogenizing optical system 27 is constituted by, for example, a light pipe (calloscope) or a fly-eye lens.

  In the image adding unit 3, an air gap prism 31 is provided at a position where the light emitted from the light source unit 2 reaches. A micromirror array 32 is provided on the side of the air gap prism 31. In the micromirror array 32, a plurality of micromirrors are integrated in a matrix so that the angles of the reflecting surfaces can be changed independently, and the micromirrors are incident by controlling the angles of these micromirrors. The light is selectively reflected and reflected by adding a monochrome image to the incident light.

  As shown in FIG. 2, the air gap prism 31 includes two prisms 33 and 34 each having a right triangular prism shape, and a wedge-shaped gap (air gap) 35 disposed between the bottom surfaces. Depending on the difference, incident light can be divided into reflection and transmission. As a result, the light incident on the prism 33 from the light source unit 2 is reflected by the bottom surface 33 a of the prism 33 and is emitted toward the micromirror array 32, but is reflected substantially in front by the micromirror array 32 and is reflected on the prism 33. The re-incident light passes through the bottom surface 33 a of the prism 33, passes through the prism 34, and goes out of the image adding unit 3.

  As shown in FIG. 1, the projection optical unit 4 is disposed at a position sandwiching the air gap prism 31 together with the micromirror array 32, and spreads light incident from the air gap prism 31 toward the outside of the projection apparatus 1. While exiting. The projection optical unit 4 is composed of, for example, a plurality of lenses (not shown).

  In the detection unit 5, a splitter 51 is provided that is interposed in the optical path between the light source unit 2 and the image adding unit 3 and reflects a part of the light emitted from the light source unit 2 while transmitting most of the light. In addition, a lens 52 that collects the light reflected by the splitter 51 is provided, and a light receiving member 53 on which the light collected by the lens 52 enters is provided.

  As shown in FIG. 3, in the light receiving member 53, an X1 sensor 54, an X2 sensor 55, a Y sensor 56, and a Z sensor 57 are arranged in a matrix of 2 rows and 2 columns. The X1 sensor 54 is provided with a light receiving element and an X1 filter that covers the light receiving element, and the X2 sensor 55 is provided with a light receiving element and an X2 filter that covers the light receiving element. Similarly, the Y sensor 56 is provided with a light receiving element and a Y filter, and the Z sensor 57 is provided with a light receiving element and a Z filter. Each filter can be realized by, for example, a multilayer film in which the thickness of each layer is optimally designed. The wavelength sensitivity characteristic of each sensor is determined by the product of the wavelength transmission characteristic of each filter and the wavelength sensitivity characteristic of the light receiving element.

FIG. 4 illustrates the color matching function of the XYZ display system, the sensitivity of each sensor, and the light emission characteristics of each LED. In FIG. 4, line C _X , line C _Y , and line C _Z indicate color matching functions of stimulus value X, stimulus value Y, and stimulus value Z, respectively. These color matching functions are described in, for example, “JIS Z 8701”. Moreover, line S _X1 , line S _X2 , line S _Y , and line S _Z indicate the wavelength sensitivity characteristics of the X 1 sensor 54, X 2 sensor 55, Y sensor 56, and Z sensor 57, respectively. Furthermore, the line _{L R,} the line _{L G,} the line _{L B,} respectively, a red LED, a green LED and shows an example of emission characteristics of the blue LED.

As shown in FIG. 4, the wavelength sensitivity characteristic (line S _X1 ) of the X1 sensor 54 has a short wavelength peak in the color matching function (line C _X ) of the stimulus value X, that is, a position where the wavelength is about 440 nanometers. It almost coincides with the peak at. Therefore, the X1 sensor 54 detects a portion including this peak in the stimulus value X, for example, a portion having a wavelength of 500 nanometers or less at the stimulus value X. Further, the wavelength sensitivity characteristic (line S _X2 ) of the X2 sensor 55 is substantially the same as the peak on the long wavelength side in the color matching function (line C _X ) of the stimulus value X, that is, the peak at a wavelength of about 595 nm. Match. Therefore, the X2 sensor 55 detects a portion including this peak in the stimulation value X, for example, a portion having a wavelength of 500 nanometers or more at the stimulation value X. Further, the wavelength sensitivity characteristic (line S _Y ) of the Y sensor 56 substantially matches the color matching function (line C _Y ) of the stimulus value Y, and the stimulus value Y is detected. Furthermore, the wavelength sensitivity characteristic (line S _Z ) of the Z sensor 57 substantially matches the color matching function (line C _Z ) of the stimulus value Z, and the stimulus value Z is detected. Each sensor outputs a detection result to the control unit 6.

  The control unit 6 controls the outputs of the red LED 21R, the green LED 21G, and the blue LED 21B of the light source unit 2 based on the outputs of the X1 sensor 54, the X2 sensor 55, the Y sensor 56, and the Z sensor 57. For example, the control unit 6 drives the light source unit 2 in a time division manner. That is, the red LED 21R, the green LED 21G, and the blue LED 21B are repeatedly turned on one by one. In addition, each sensor of the detection unit 5 sends a signal corresponding to an integral value of the amount of light detected at a time longer than the driving cycle of the light source unit 2, for example, an integral multiple of the driving cycle of the light source unit 2, to the control unit 6. Output. And the control part 6 controls the output of each LED based on this output result. The LED output is controlled by adjusting, for example, the light emission pulse width, that is, the light emission time. Or you may adjust the peak value of the electric current value supplied to LED.

Next, the operation of the projection apparatus according to this embodiment will be described.
FIG. 5 is a graph schematically illustrating the emission spectrum of each LED and the wavelength sensitivity characteristics of each sensor in the present embodiment, with the horizontal axis representing wavelength and the vertical axis representing intensity and sensitivity. It corresponds to.
Hereinafter, a description will be given with reference to FIGS.

  First, the control unit 6 causes the light source unit 2 to emit light in a time division manner. That is, the red LED 21R, the green LED 21G, and the blue LED 21B are repeatedly turned on one by one. In synchronization with this, the micromirror array 32 of the image adding unit 3 sequentially forms images corresponding to the respective colors.

  The red light emitted from the red LED 21 </ b> R is collimated by the collimator 22 </ b> R and enters the dichroic prism 23. Then, the light is reflected by the red light reflecting multilayer film mirror 24 and emitted from the light emitting surface 26. The green light emitted from the green LED 21G is collimated by the collimator 22G and enters the dichroic prism 23. Then, the light passes through the dichroic prism 23 linearly and is emitted from the light exit surface 26. Further, the blue light emitted from the blue LED 21B is collimated by the collimator 22B and enters the dichroic prism 23. Then, the light is reflected by the blue light reflecting multilayer mirror 25 and emitted from the light emitting surface 26. The light emitted from the light emitting surface 26 is made uniform by the uniformizing optical system 27 and is emitted from the light source unit 2.

The light emitted from the light source unit 2 reaches the splitter 51, most of which is transmitted and part of it is reflected. The light transmitted through the splitter 51 is incident on the prism 33 of the air gap prism 31 via the optical path L ₁ reaches the bottom surface 33a of the prism 33, toward the micro mirror array 32 is reflected on the bottom surface 33a. Then, an image is added by the micromirror array 32 and is reflected substantially toward the front. The light reflected by the micro mirror array 32, then re-enters the prism 33 of the air gap prism 31 via the optical path L ₂ reaches the bottom surface 33a, passes while refracting the bottom 33a, the prism 34 while being refracted The light is transmitted, is expanded by the projection optical unit 4, and is emitted toward the outside of the projection apparatus 1. Then, the image is projected onto a screen (not shown) provided outside the projection apparatus 1.

On the other hand, the light reflected by the splitter 51 is condensed on the light receiving member 53 by the lens 52. The spectrum of the light at this time is a spectrum as shown by line L _R , line L _G , and line L _B in FIG. Then, each sensor of the light receiving member 53 detects light in each wavelength region. Specifically, as schematically shown in FIG. 5, each sensor detects the area (integrated value) of a region where the sensitivity spectrum of this sensor and the spectrum of incident light overlap. For example, X2 sensor 55 detects the amount of light corresponding to the area of a region A which is defined by lines _{S X2} and the line _{L R.} Each sensor outputs to the control unit 6 an integrated value of light received for a time longer than the driving cycle of the light source unit 2, for example, an integral multiple of the driving cycle of the light source unit 2.

The controller 6 outputs the outputs of the X1 sensor 54, the X2 sensor 55, the Y sensor 56, and the Z sensor 57, that is, the intensity obtained for each stimulus value of the XYZ color system for each LED of the light source unit 2. Convert to Specifically, the output signal strength of the X1 sensor 54 is X1, the output signal strength of the X2 sensor 55 is X2, the output signal strength of the Y sensor 56 is Y, the output signal strength of the Z sensor 57 is Z, and red When the intensity of the _LED is R _LED , the intensity of the green LED is G _LED, and the intensity of the blue LED is B _LED , the parameters R _LED , G _LED , and B _LED are calculated by the following formulas (1) to (4). To do. Note that a _R , b _R , c _R , a _G , b _G , c _G , a _B , b _B , and c _B are coefficients.

X = X1 + X2 (1)

R _LED = a _R × X + b _R × Y + c _R × Z (2)

G _LED = a _G × X + b _G × Y + c _G × Z (3)

B _LED = a _B × X + b _B × Y + c _B × Z (4)

At this time, the chromaticity (x, y) of the light emitted from the light source unit 2 can be expressed by the following mathematical formulas (5) and (6). The luminance can be represented by Y.

x = X / (X + Y + Z) (5)

y = Y / (X + Y + Z) (6)

And the detected values (R _LED , G _LED , B _LED ) calculated by the above formulas (1) to (4) are values of the intensity of each component of the light to be emitted to the light source unit 2, that is, the target Compare with the values (R ₀ , G ₀ , B ₀ ). When the light source unit 2 is driven in a time-sharing manner, the target value is a pseudo white light value obtained by integrating the light emitted from the light source unit 2 over an integral multiple of the drive cycle. To do. When the detection values (R _LED , G _LED , B _LED ) are different from the target values (R ₀ , G ₀ , B ₀ ), the output of each LED is set so that the detection values approach the target values. adjust. For example, when the value of R _LED that is the detection value of the red component is smaller than the value of R ₀ that is the target value, the pulse width of the red LED 21R is increased to increase the output of red light. In this way, the color balance of the emitted light from the light source unit 2, that is, the color and brightness of the pseudo white light obtained by time integration is compensated. Thereby, feedback control of the light source unit 2 is performed.

  Then, by repeating the above-described feedback control at a constant period, the color and luminance of the emitted light from the light source unit 2 are sequentially corrected and kept converged toward the target value. Thereby, even if the light emission characteristics of each LED of the light source unit 2 change due to the influence of temperature or the like, it is possible to prevent the color and luminance of the emitted light from being greatly collapsed, and to suppress the color shift of the image.

Next, the effect of this embodiment will be described.
In the present embodiment, the projection device 1 is provided with the detection unit 5 and the control unit 6, detects light emitted from the light source unit 2, and performs feedback control of the light source unit 2 based on the detection result. It is possible to compensate for variations in the color and luminance of the emitted light from the unit 2 and to prevent color misregistration of the image.

Moreover, since the detection unit 5 detects light for each stimulus value of the XYZ color system, it detects light more accurately than when detecting light for each component of the RGB color system. be able to. Hereinafter, this effect will be described in more detail.
FIG. 6 is a graph showing the color matching function of the RGB color system, with the wavelength on the horizontal axis and the intensity on the vertical axis.

  As shown in FIG. 6, the RGB color system color matching function includes a region M in which the R component has a negative value. However, since no negative component can be detected using any sensor, this negative region is ignored when light is detected for each RGB component. For this reason, in this case, the color and luminance of the emitted light from the light source unit 2 cannot be completely grasped, and the compensation operation is necessarily incomplete. On the other hand, in this embodiment, the detection unit 5 detects light for each stimulus value of the XYZ color system. As shown in FIG. 4, in the color matching function of the XYZ color system, there is no region where the stimulus value is a negative value. Therefore, light can be detected accurately, and a highly accurate compensation operation is possible.

  Further, as shown in FIG. 4, since the color matching function of the stimulus value X has two peaks, in the present embodiment, two sensors that match the respective peaks, that is, the X1 sensor 54 and the X2 sensor 55 are used. The intensity is measured for each peak of the stimulus value X. Therefore, a total of four sensors are provided in combination with the Y sensor 56 and the Z sensor 57.

  On the other hand, it is also conceivable that the X1 sensor is not provided and the peak on the short wavelength side in the stimulus value X is ignored. However, if it does in this way, it will become impossible to detect received light correctly. For example, the light represented by the color matching function shown in FIG. 4 is completely white light, and its chromaticity is (x, y) = (0.333, 0.333), as in this embodiment. When the X1 sensor is provided and this light is detected by four sensors, (x, y) = (0.333, 0.333) can be detected. That is, true chromaticity can be detected. On the other hand, if the X1 sensor is not provided and the short wavelength side peak of the stimulus value X is ignored, a signal in the wavelength range of 500 nanometers or less in the stimulus value X is lost, so the detected chromaticity is (x , Y) = (0.294, 0.353), and the chromaticity indicates a slightly light blue white. At this time, the error with respect to the true chromaticity (0.333, 0.333) is (0.039, 0.020). Since the human eye is said to be able to recognize a difference of 0.002 in terms of chromaticity, this error cannot be ignored and has a serious adverse effect on image quality. That is, even if it tries to match the color of the emitted light of the light source unit with a perfect white color, it actually becomes a light white color.

  Further, since the detection wavelength range of the X1 sensor is close to the detection wavelength range of the Z sensor, a value obtained by multiplying the detection result of the Z sensor by a constant coefficient α may be regarded as the detection result of the X1 sensor without providing the X1 sensor. Conceivable. That is, X1 = α × Z. In this case, the detection unit may be provided with three sensors, that is, an X2 sensor, a Y sensor, and a Z sensor.

  However, even with this method, it is impossible to accurately grasp the characteristics of light. For example, regarding the emitted light from the light source unit, the chromaticity (x, y) in the initial state is (0.333, 0.333), the luminance (Y) is 108.1, and the emitted light from the blue light emitting element Assuming a case where the wavelength is shifted to the longer wavelength side by 10 nanometers, the detection result of the light after the shift is as shown in Table 1. In Table 1, “4-sensor method” indicates the method of this embodiment, that is, a method of providing an X1 light receiving element, and “3-sensor method” indicates the method of the comparative example, that is, the X1 light-receiving element. A method in which a value obtained by multiplying the Z sensor by a constant coefficient α is regarded as the output of the X1 sensor without being provided. The light emitted from the light source unit is pseudo white light obtained by temporally integrating the light emitted from each light emitting element when the light source unit is a time division method, and the light source unit is not a time division method. Means white light obtained by spatially mixing the light emitted from each light emitting element.

  As shown in Table 1, in the initial state, the chromaticity and the luminance are equal to each other in the 3-sensor system and the 4-sensor system. This is because the value of the coefficient α is adjusted so as to be so. However, after the shift, the chromaticity x is shifted by −0.004 and the chromaticity y is shifted by +0.002 between the 4-sensor system and the 3-sensor system. The result detected by the 4-detection method is a true value. As described above, since it is said that the human eye can recognize a chromaticity difference of about 0.002, the three-sensor method causes an error that can be recognized by a person when detecting light.

  On the other hand, in this embodiment, since the 4-sensor system provided with the X1 sensor is adopted, it is possible to accurately detect the light emitted from the light source unit and control the light source unit with high accuracy. As described above, according to the present embodiment, it is possible to realize a projection apparatus with little image color misregistration.

Furthermore, in the present embodiment, an air gap prism 31 is provided in the image adding unit 3. Air gap prism, by a slight difference of the incident angle to the bottom surface 33a, reflects the light path L _1, since it is possible to transmit light path L _2, light is incident from substantially the front with respect to the micro mirror array 32, Even if light is reflected substantially in front by the micromirror array 32, only the reflected light of the micromirror array 32 can be emitted toward the projection optical unit 4. Thereby, the distortion of the image in the micromirror array 32 can be suppressed and the reflection efficiency can be increased.

  The present invention has been described above with reference to the embodiment. However, the present invention is not limited to this embodiment. For example, those in which those skilled in the art appropriately added, deleted, and changed the design of the above-described embodiments are also included in the scope of the present invention as long as they have the gist of the present invention.

  For example, in the above-described embodiment, an example in which the light emitting element is an LED has been described. However, the present invention is not limited to this, and for example, the light emitting element may be an LD (Laser Diode).

  In the above-described embodiment, an example in which the image adding unit is configured by a micromirror array has been described. However, the present invention is not limited to this, and the image adding unit may be configured by a liquid crystal panel. In this case, the liquid crystal panel may be a reflection type or a transmission type. Further, the liquid crystal panel may be a color liquid crystal panel, and the light source unit may be a non-time-division type light source unit that spatially mixes light of RGB colors and emits white light.

  Furthermore, in the above-described embodiment, the example in which the output of each light emitting element is adjusted by adjusting the peak width of each light emitting element is shown, but the present invention is not limited to this, and the light emitting element is supplied to each light emitting element. You may control the output of each light emitting element by adjusting the magnitude | size of a voltage or an electric current.

  Furthermore, in the above-described embodiment, the projection apparatus is an example of a front projection type apparatus that projects an image onto an external screen or the like from the front side. However, the projection apparatus incorporates a screen, and this screen Alternatively, a rear projection type device that projects an image from the back side may be used.

It is a figure which illustrates the projection apparatus which concerns on embodiment of this invention. It is a side view which illustrates the image addition part in this embodiment. It is a perspective view which illustrates the light receiving member in this embodiment. FIG. 6 is a graph illustrating the color matching function of the XYZ display system, the wavelength sensitivity characteristics of each sensor, and the light emission characteristics of each LED, with the wavelength on the horizontal axis and the intensity and sensitivity on the vertical axis. It is a graph which illustrates typically the light emission spectrum of each LED in this embodiment, and the wavelength sensitivity characteristic of each sensor in this embodiment, taking a wavelength on a horizontal axis and taking intensity and sensitivity on a vertical axis. It is a graph which shows a color matching function of an RGB color system, taking a wavelength on the horizontal axis and taking an intensity on the vertical axis.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projection device, 2 Light source part, 3 Image addition part, 4 Projection optical part, 5 Detection part, 6 Control part, 21R Red LED, 21G Green LED, 21B Blue LED, 22R, 22G, 22B Collimator, 23 Dichroic prism, 24 Red light reflecting multilayer mirror, 25 Blue light reflecting multilayer mirror, 26 Light exit surface, 27 Uniform optical system, 31 Air gap prism, 32 Micro mirror array, 33 Prism, 33a Bottom surface, 34 Prism, 35 Gap, 51 Splitter, 52 lens, 53 light receiving member, 54 X1 sensor, 55 X2 sensor, 56 Y sensor, 57 Z sensor, A, M region, C _X stimulus value X line, _CY stimulus value Y, etc. line representing the color matching function, C _Z stimulus value line representing the color matching function of Z, the line representing the wavelength sensitivity characteristics of the S _{X1 X1} sensors, S Line representing a ₂ X2 sensor wavelength sensitivity characteristics _{S Y} Y sensor lines representing the wavelength sensitivity characteristics, the line representing the wavelength sensitivity characteristics of _{S Z} Z sensors, lines representing the light emission characteristics of _{L R} red LED, _{L G} green LED line representing the light emission characteristics of a line representing the light emission characteristics of the _{L B} blue _LED, L 1, _{L 2} optical path

Claims (3)

A light source unit;
An image adding unit for adding an image to the light emitted from the light source unit;
A projection optical unit that projects the light with the image added thereto;
A detection unit for detecting light emitted from the light source unit;
A control unit that controls the light source unit based on a detection result of the detection unit;
With
The light source unit is
A red light emitting element that emits red light;
A green light emitting element that emits green light;
A blue light emitting element that emits blue light;
Have
The detector is
An X1 sensor for detecting a portion including a peak on the short wavelength side of the stimulus value X of the XYZ color system;
An X2 sensor that detects a portion including a peak on the long wavelength side of the stimulus value X of the XYZ color system;
A Y sensor for detecting a stimulus value Y of the XYZ color system;
A Z sensor for detecting a stimulus value Z of the XYZ color system;
A projection apparatus comprising:   The projection apparatus according to claim 1, wherein the red light emitting element, the green light emitting element, and the blue light emitting element are a red light emitting diode, a green light emitting diode, and a blue light emitting diode, respectively. The light source unit causes the red light emitting element, the green light emitting element, and the blue light emitting element to emit light in a time-sharing manner,
The image adding unit includes a micromirror array that forms an image corresponding to each color in synchronization with light emission of the red light emitting element, the green light emitting element, and the blue light emitting element,
The detection unit outputs a signal corresponding to an integral value of the light amount detected at a time that is an integral multiple of the driving cycle of the light source unit,
3. The projection apparatus according to claim 1, wherein the control unit controls a light emission pulse width of each of the red light emitting element, the green light emitting element, and the blue light emitting element.

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