JP2011090061A - Scanning type display device optical system and scanning type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate and synthesize light having a wavelength not limited to the three primary colors of white light, to perform desired color-separation adjustment control by DMD, to realize subtle hues, which is difficult to realize with a conventional projector. Scanning that can project any full-color image, matches a full-spec ultra-high-resolution image that is closest to the natural color, and also supports a three-dimensional full-color image that appears to be deep An object of the present invention is to provide a mold display device optical system.
An optical system of a scanning display device according to the present invention decomposes light from a lamp 1 for each wavelength by a concave diffraction grating 7, performs adjustment for each wavelength decomposed by a DMD 8, and uses a concave mirror 9 for each wavelength. And a full color image of an arbitrary color is projected.
[Selection] Figure 1

Description

  The present invention uses at least two spectroscopic elements such as a reflective diffractive element and a transmissive diffractive element, and a high-speed spatial modulation element represented by DMD (Digital Mirror Device, officially Digital Micromirror Device). The present invention relates to a line scanning display optical system and a line scanning display device that form an image in which each pixel has an arbitrary spectral distribution by scanning.

  Conventionally, a light source that emits white light, a continuous spectrum light forming unit that converts the white light emitted by the light source into spectral light continuously distributed in space, and each pixel of a color image to be displayed Projection-type display including a light valve that drives each pixel element arranged secondarily to time-division-modulate incident light, and a spectral light scanning unit that cyclically scans continuous spectral light in one direction on the light valve. An apparatus (see, for example, US Pat. No. 6,099,097, FIG. 1), at least one light source configured to provide spectrally and spatially resolved light, and spectral and spatial resolution A spatial light modulator configured to receive and modulate the received light and selectively send a selected spatial color from the light source to form a set of partial images; and to receive the set of partial images A scanning display optical system and a scanning display comprising: a display system comprising: at least one scanning device configured to scan the set of partial images over the entire display area to create a full frame color image; An apparatus (for example, see Patent Document 2, Claim 1, and FIGS. 1 and 2) is known.

JP 2004-240293 A JP 2005-326837 A

However, in the conventional scanning display device optical system and scanning display device, the degree of color to be displayed is synthesized by combining light of wavelengths not limited to R (red light), G (green light), and B (blue light). The specific optical system to be changed delicately is not clearly and uniquely described, and it has been extremely difficult to realize. This is because there was a technical difficulty to realize with an actual device.
For this reason, the conventional scanning display optical system and scanning display cannot display an image in which each pixel has an arbitrary spectral distribution. For example, an ultra-high resolution image (high-definition image) that faithfully reproduces natural colors. ) And a 3D full-color image that appears to be deeper could not be displayed.

  In addition, in the conventional scanning display device optical system and scanning display device realized experimentally, color display based on conditional color mixing (R, G, B) is fundamental, so due to differences in individual color matching functions, There was a problem that the color perceived by the observer was different. In other words, the image of the target object captured by the camera has the same color on the display device as the original color for an observer who has the same color matching function as the standard color matching function. However, the same color was not seen by observers with different color matching functions.

  This is more conspicuous for an observer with color blindness, which may be a serious problem in a display device using three LED light sources. Further, in the synthesis of the limited three primary colors of R, G, and B, a color at a single wavelength and a color in the vicinity thereof cannot be displayed, and color reproduction is performed in a region where the original chromaticity coordinates are limited.

  Moreover, in the color vision inspection related to driving, the display of the traffic light using the LED could not make an image reproducing the spectral distribution of the LED with the conventional display device. It could not be done with a display device.

  Therefore, in the present invention, all of the spectral elements using a spatial modulation element such as DMD that has two spectroscopic elements at the same time, finely decomposes the wavelength of white light to a few nanometers or less, and can independently control the color classification adjustment, It is an object of the present invention to provide a scanning display device optical system and a scanning display device capable of reproducing the hue by controlling the wavelength distribution.

  For example, at least two optical elements (spectral elements) such as a reflective diffractive element and a transmissive diffractive element are used at the same time, and the three primary colors of white light (R (red light), G (green light), and B (blue light)) are used. Perform separation and synthesis with light of unlimited wavelength, perform desired color-separation adjustment control with a high-speed spatial modulator such as DMD placed between at least two optical elements (spectral elements), and reproduce subtle spectral distribution, An image in which each pixel has an arbitrary spectral distribution, which was difficult to realize with a conventional projection apparatus (similar to the generation of a spectral distribution by a conventional programmable light source. However, a programmable light source displays one type of spectral distribution in terms of illumination. Scanning table that can display ultra-high-resolution images (high-definition) that fully reproduces the natural spectral distribution and three-dimensional image display that fully reproduces color. And to provide an apparatus optical system and a scanning display.

  In order to solve the above-mentioned problem, the invention of claim 1 is configured such that the light from the white light source is decomposed for each wavelength by the first spectroscopic element, and the transmission intensity for each decomposed wavelength is adjusted by the spatial modulation element for the time. Or by changing the transmittance, and by combining each wavelength with the second spectral element, each pixel has a one-dimensional image (one-dimensional image corresponding to the original white slit) having an arbitrary wavelength distribution. By forming and scanning and projecting the one-dimensional image having an arbitrary wavelength distribution in the vertical direction or the horizontal direction by a scanning projection system, each pixel can display a two-dimensional image having an arbitrary wavelength distribution. This is a characteristic scanning image display device.

That is,
According to the first aspect of the present invention, the light from the white light source is split and combined by at least two spectroscopic elements, and spatially modulated by the spatial modulation element between the spectroscopic and combining, and the modulated and synthesized light is scanned by the scanning unit. An optical system of a scanning display device that projects an image on a screen and projects a full-color image.

  According to the second aspect of the invention, the light from the white light source is decomposed for each wavelength by the first spectroscopic element, the resolution is adjusted for each wavelength by the spatial modulation element, and the second spectroscopic element is used for each wavelength. An optical system of a scanning display device that performs composition and projects a full-color image of an arbitrary color onto a display device by a scanning unit.

  According to a third aspect of the present invention, in the scanning display device optical system according to the first or second aspect, the transmittance of each wavelength is adjusted by the spatial modulation element.

  According to a fourth aspect of the present invention, the light from the white light source is slit-shaped or fan-shaped, and the light from the light reaches the first spectroscopic element. The scanning display device optical system described.

  5. The scanning display device optical system according to claim 4, wherein the spectral direction is perpendicular to the planar direction of the slit-shaped or fan-shaped light beam. It is.

  According to a sixth aspect of the present invention, in the scanning display device optical system according to the fourth aspect, the slit member and the spatial modulation element are in a conjugate relationship through the first spectroscopic element.

  In the invention according to claim 7, the light from the white light source is decomposed for each wavelength by the first spectroscopic element, the light having the decomposed wavelength is adjusted for each wavelength by the DMD, and the light having the adjusted wavelength is The scanning display device optical system is characterized in that a full-color image of an arbitrary color is projected onto a screen through a projection lens after being synthesized by a second spectral element.

  The invention according to claim 8 is the scanning display device optical system according to claim 7, wherein one of the first light-splitting element and the second light-splitting element is a reflective concave diffraction element. It is.

  The invention according to claim 9 is the scanning display device optical system according to claim 7, wherein either the first light-splitting element or the second light-splitting element is a transmissive diffraction element. is there.

  According to a tenth aspect of the present invention, a first light splitting element that decomposes white light into light of a plurality of wavelengths, and a light that is decomposed by the first light splitting element and adjusted to a desired color for each of the light of a plurality of wavelengths is reflected. A scanning display apparatus optical system comprising: a DMD; a second spectral element that combines light reflected by the DMD; and a projection lens that projects light that has passed through the second spectral element. .

  The invention according to claim 11 is a first spectral element that decomposes white light into light of a plurality of wavelengths, and a DMD that adjusts and reflects the light decomposed by the first spectral element for each wavelength of several nanometers or less. A scanning display device optical system comprising: a second spectral element that synthesizes light reflected by the DMD; and a projection lens that projects the light that has passed through the second spectral element.

  The invention according to claim 12 is the scanning display device optical system according to claim 10 or 11, further comprising a concave mirror that further reflects the light reflected by the DMD.

  According to a thirteenth aspect of the present invention, at least one of the first spectroscopic element and the second spectroscopic element is planar, and light beams passing through the element are parallel. The scanning display device optical system according to any one of 12 above.

  The invention described in claim 14 projects the synthesized wavelength or light onto a mirror that rotates within a predetermined angle range, and projects an image on a screen. The scanning display device optical system according to claim 1.

  According to a fifteenth aspect of the present invention, there is provided a scanning display device comprising the scanning display device optical system according to any one of the first to fourteenth aspects.

  According to the present invention, at least two spectroscopic elements such as a reflective diffractive element and a transmissive diffractive element are used at the same time for the three primary colors of white light (R (red light), G (green light), B (blue light)). Separation / synthesis is performed using light of an unlimited wavelength, and desired spectral transmittance control is performed by a high-speed spatial modulation element such as DMD. Each pixel has an arbitrary spectral distribution, which is difficult to realize with conventional display devices. It is possible to project an image having a high-resolution image (high definition) in which natural colors are completely reproduced and a three-dimensional image in which color reproduction is complete.

FIG. 1 is an optical diagram of a first embodiment of an optical system of a scanning display device according to the present invention. FIG. 2 is an enlarged view of an optical system showing an enlarged optical path from the slit member shown in FIG. 1 to the transmissive diffraction grating. FIG. 3 is an optical diagram of the second embodiment of the scanning display device optical system according to the present invention. FIG. 4 is an optical view of a third embodiment of the scanning display device optical system according to the present invention.

Example 1
FIG. 1 is an optical diagram showing a first embodiment of an optical system of a scanning display device according to the present invention.

  The scanning display optical system includes a lamp 1, which is a white light source, a light pipe 2, relay lenses 3, 4, a slit member 5, a folding mirror 6, a concave diffraction grating (first optical element) 7 which is a reflective diffraction element, DMD 8, which is a spatial modulation element, concave mirror (second optical element) 9, transmissive diffraction grating 10, which is a transmissive diffractive element, relay lens 11, scanner mirror 12, encoder device (note that the encoder device is not shown), projection It has a lens 13. The light synthesized by the scanning display device optical system becomes a one-dimensional image (sometimes fan-shaped) 15 ′ having a spectral distribution for each pixel, and this one-dimensional image is applied to the screen S by the scanning optical system. Scanning projection is performed, and a two-dimensional image in which each pixel has an arbitrary wavelength distribution is displayed. Reference numeral 1a denotes an elliptical reflector.

  As shown in FIG. 1, this scanning display device optical system has at least two diffraction elements, that is, a concave diffraction grating 7 as a reflection diffraction element and a transmission diffraction grating 10 as a transmission diffraction element at the same time. .

  Here, a xenon lamp may be used as the lamp 1, and the brightness is 300W to 500W. The light pipe 2 has a numerical aperture NA of 0.5, a long side of about 2.1 mm, a short side of 0.01 to 0.1 mm, and an optimum short side dimension of 0.03 to 0.3 mm. 05 mm. The relay lens 4 desirably has a magnification of about 5 times.

  The slit member 5 has a numerical aperture NA of 0.1, a length of about 10.0 mm to 11.0 mm, and an optimum length of 10.506 mm. The size of the hole diameter of the slit member 5 is 0.1 to 0.5 mm, and the optimum size is about 0.2 mm.

  The concave diffraction grating 7 has a radius of curvature r of about 120 mm to 130 mm, and 126.9 mm is used as an optimal example. The radius of curvature of the concave mirror 9 is also the same as that of the concave diffraction grating 7. It should be noted that the light reflection position on the concave mirror 9 is located on the far side on the paper surface of FIG.

DMD8, which is an optical modulation element, is 0.7 inches, vertical and horizontal (14 mm to 15 mm) × (10 mm to 11 mm), and an optimal example is one having 14.008 mm × 10.506 mm. In addition, it has a size of about 13.2 mm in the spectral direction (400 nm to 700 nm). The inclination angle of DMD is approximately 20 to 24 degrees.
The transmissive diffraction grating 10 has about 1000 diffraction gratings per 1 mm.

  The focal length f of the relay lens 11 is f = 24.4 mm.

  The scanning angle of the scanner mirror 12 is (scanning angle) ± 8 degrees, and the mirror size is 4 mm × 4 mm.

  The resonance frequency of the scanner mirror 12 is 8 kHz. The scanning wavelength is multi-wavelength and a full color image can be transferred. Further, although scanning is performed for the pitch of the image, this pitch can be changed for each image, and scanning can be freely changed according to an arbitrary full-color image.

  The projection lens 13 has a focal length f of 708.6 mm, a distance from the projection lens 13 to the screen S of 700 mm, and a screen size of 20 inches.

  The slit member 5 and the DMD 8 that is a spatial modulation element are conjugated via a concave mirror 7 that is a first optical element.

  The light from the white light source is made into a slit shape or a sector shape by the slit member 5, and these slit shape or sector shape light fluxes are guided to the concave diffraction grating 7 which is the first optical element via the folding mirror 6. A direction perpendicular to the planar direction of the slit shape or the sector shape is a spectral direction.

With the above configuration, the light from the white light source is decomposed for each wavelength by the first spectroscopic element, the spectral transmittance is adjusted by DMD according to the on / off time interval of the mirror at each position, and the second spectroscopic element is used. By combining each wavelength, a one-dimensional image having an arbitrary wavelength distribution corresponding to each pixel is formed, and this one-dimensional image is formed on a scanning screen by a scanning scanning display optical system having a scanner mirror 12. Projecting and displaying a two-dimensional image in which each pixel has an arbitrary spectral distribution. In addition, the light from the white light source is dispersed with a reflective diffraction element,
The reflected and dispersed light is reflected by the DMD 8 by adjusting the amount of reflection for each wavelength element in time, and the reflected spectrally dispersed light is combined by the transmissive diffraction element 10 and transmitted. A full-color two-dimensional image in which each pixel has an arbitrary spectral distribution is projected onto the screen S via the scanner mirror 12 and the projection lens 13. The reflective diffraction element is a reflective concave surface.

  The one-dimensional image after color synthesis is projected onto a mirror that rotates within a predetermined angle range, and light is scanned on the screen S. Furthermore, the projection apparatus according to the present invention includes these scanning display device optical systems.

  The DMD 8 is controlled to synthesize a desired spectral distribution by the arithmetic control unit 14, and the light of each wavelength component field that has been decomposed in detail is reflected by the DMD 8, reflected by the concave mirror 9, and transmitted through the transmissive diffraction element 10. Then, the detailed synthesis of the spectral distribution is performed. However, the present invention is not limited to this, and it is possible to realize a hue that matches a full-spec ultra-high resolution image (high definition) closest to a natural color. 2 is an enlarged view of the optical system showing an enlarged optical path from the slit member 5 to the transmissive diffraction grating 10 shown in FIG.

  Note that the light source is not limited to a white light source, white light or a light source having a wide wavelength width corresponding to the light source, a composite light source in which a plurality of light sources are used to artificially widen the wavelength width, and a discrete wavelength range of a wide wavelength range. It is possible even with a light source.

  Also, a video information providing unit is added to the scanning display device optical system of FIG. 1, and a disc on which video data is recorded is placed in the video information providing unit and provided to the arithmetic control unit. Alternatively, video information transmitted through radio waves or optical cables can be provided to the arithmetic unit.

Control of the spatial modulator by the arithmetic control unit 14 for displaying an arbitrary spectral distribution of 256 pixels vertically and 320 pixels horizontally is as follows.
In order to realize 30 images / second (FPS), the line scan requires spatial modulation of 30 × 256 (number of rows) 7680 times. When this is compared with the rewriting speed of DMD or the like, if rewriting in units of frames can be performed at about 32 KHz by DMD, the gradation becomes 4 gradations and is not sufficient. However, since DMD has a large number of pixels such as high-definition support (1920 x 1080 pixels), if you want to target a full spectral image of about 320 x 256 pixels, make DMD 3 x 3 correspond to one pixel. Thus, a pseudo gradation can be given. Thus, spatial modulation can be realized by temporal intensity modulation by turning on / off the DMD mirror and high-definition pixels of the DMD. Spatial modulation is an operation for converting the intensity of light from the light source side of a certain wavelength corresponding to the dispersed pixels into an appropriate intensity to form one pixel of the final two-dimensional image.
By the way, if a pseudo gradation is produced using 3 × 3 pixels, nine pixels are used, and each of them is on or off, so 2 9 = 512 gradations. Furthermore, when multiplied by the original time modulation, it becomes 512 × 4, 2048 gradations, and it has a sufficiently sufficient gradation. In some cases, priority may be given to resolution and frame rate. For example, in the case of 60 FPS instead of 30 FPS, the gradation by the temporal control becomes two gradations, and the gradation by spatial modulation becomes 1024 gradations.
In addition, by using a high-definition DMD (such as the number of horizontal pixels of 4000), a high-definition class display in which each pixel is faithfully reproduced can be displayed.
In addition, a spectrum meter for adjusting the spectral distribution of the light source may be necessary. In this case, after the light from the light source is guided to the slit 5 and before being guided to the first spectroscopic element, an auxiliary spectroscopic element or the like is introduced on the optical path to generate a slit with an adjusted spectral distribution. There are things to do.

Note that 16 is a polarizer for obtaining linearly polarized light in a certain direction. When a polarizing element is used as a spectroscopic element, the p-polarized light and the s-polarized light have different spectral intensity characteristics, and a desired spectral distribution may not be obtained. Yes, in that case it is necessary.
(Example 2)
FIG. 3 is a diagram showing a scanning display device optical system according to the second embodiment of the present invention.

  The light from the white light source (white light) is scrambled by the light pipe 2 and dispersed through the slit member 5 and the reflective concave diffraction element 7. The component for each wavelength that has been split is further controlled by DMD 8 to transmit to the rear part of the optical system, further reflected by concave mirror 9, and transmitted through transmission type diffractive element (linear diffractive element) 10. The wavelength component decomposed by the element 7 is recombined.

In order to perform synthesis for obtaining a desired spectral distribution by the arithmetic control unit 14, each spectral component is reflected by the DMD 8, reflected by the concave mirror 9, and re-synthesized through the transmissive diffraction element 10. I do. Reference numeral 17 denotes a reflecting mirror.
(Third embodiment)
FIG. 4 is a diagram showing a scanning display device optical system of a scanning display device according to a third embodiment of the present invention.

  In the third embodiment, a scanning display device optical system using a planar diffraction grating in which aberrations are minimized is shown.

  This scanning display device optical system includes a lamp 1, which is a white light source, a light pipe 2, two relay lenses (relay systems) 4a and 4b, a slit at the focal position of the relay lens, and transmission diffraction which is a transmission diffraction element. A grating 10a, a condensing lens 15, a DMD 8, a collimator lens 9 ', a transmissive diffraction element 10b, two relay lenses (relay systems) 11a and 11b, and a scanner mirror 12 are displayed on the screen S. The focal position of the relay lens 11a after passing through the second transmission diffraction element 10b is a position optically conjugate with the slit member 5, and a one-dimensional image having a spectral distribution is formed. A full-color image is projected and displayed on the screen S by scanning the one-dimensional image within a predetermined angle by the scanner mirror 12 as scanning means.

  The description of the same configuration as that of the first embodiment is omitted.

  Regarding the optical arrangement of the condenser lens 15, DMD 8, and collimator lens 9 ′, the number of pixels on the DMD 8 is biased due to the arrangement based on the two Shine-Pluke principles (magnification in the direction perpendicular to the paper surface). This can be solved by light amount correction from the slit member 5 on the light source side to the DMD 8. In addition, since there is a problem in the addition of the spectral distribution between the DMD 8 and the one-dimensional image having the spectral distribution, the positional relationship when spatial filtering is performed on the DMD 8 is determined by the one-dimensional image having the spectral distribution. Add them together so that they have a distribution, so that the lines have the required slope. That is, in FIG. 4, the light emitted from the lower left of the DMD 8 (for example, light near the wavelength of 800 nm) is compared to the light emitted from the upper right of the DMD 8 (for example, light near the wavelength of 400 nm). Since the magnification in the vertical direction becomes high, the modulation region in the lower left of the DMD 8 (in this case, on the long wavelength side) is originally made narrower than the light emitted from the upper right of the DMD 8. As a result, the one-dimensional image having the spectral distribution can be accurately added on the transmission type diffraction grating 10b.

  The lenses 15 and 9 'before and after the DMD 8 are fΘ lenses. These lenses are arranged parallel to the DMD.

  Since the arithmetic control unit 14 is the same as that in the first actual example, the description is omitted here.

  In order to reduce aberration, a single lens or a plurality of lenses may be provided on the optical path to the transmission diffraction grating 10a, the condenser lens 15, and the DMD 8, and / or on the optical path to the DMD 8 and the transmission diffraction element 10b. An optical system composed of lenses can also be arranged.

  The scanning display device optical system according to the present invention can enjoy images of movies, televisions, and the like in a car, in addition to projection devices such as movie theaters, rear or front projectors for home theaters, and short projection distance projectors. The present invention can also be applied to an in-vehicle projector. It can also be applied to agricultural machinery, heavy equipment such as caterpillars, HUDs (head-up displays) for mobile devices such as ships and aircraft, and glasses-type personal HUDs. be able to. Further, it is useful when it is important to accurately display the spectral distribution of a signal, such as in a driver's license. Furthermore, the present invention is completely different from conventional display devices because it can display the actual object regardless of the color matching function of the individual. Furthermore, not only the difference in the color matching function of the normal person but also the natural appearance can be provided to the color blind person, which can contribute to barrier-free.

DESCRIPTION OF SYMBOLS 1 ... Lamp 7 ... Concave diffraction grating 8 ... DMD
9 ... concave mirror

Claims (15)

The light from the white light source is split and combined by at least two spectroscopic elements, spatially modulated by a spatial modulator arranged between the spectroscopic and synthesizing, and the spatially modulated and synthesized light is projected onto the screen by the scanning means. And a scanning display device optical system for projecting a full-color image.   The light from the white light source is decomposed for each wavelength by the first spectroscopic element, the resolution is adjusted for each wavelength by the spatial modulation element, the synthesis is performed for each wavelength by the second spectroscopic element, and the scanning means arbitrarily An optical system for a scanning display device, which projects a full-color image of the above color onto a display device.   The scanning display device optical system according to claim 1, wherein transmittance is adjusted for each wavelength by the spatial modulation element.   3. The scanning display device optical system according to claim 1, wherein light from the white light source has a slit shape or a fan shape, and light from the light source reaches the first light separating element. 4.   5. The scanning display device optical system according to claim 4, wherein the spectral direction is perpendicular to the planar direction of the slit-shaped or fan-shaped light beam.   The scanning display device optical system according to claim 4, wherein the slit member and the spatial modulation element are in a conjugate relationship through the first spectroscopic element.   The light from the white light source is decomposed for each wavelength by the first spectral element, the decomposed wavelength light is adjusted for each wavelength by the DMD, and the adjusted wavelength light is synthesized by the second spectral element, An optical system for a scanning display device, which projects a full-color image of an arbitrary color onto a screen through a projection lens.   8. The scanning display device optical system according to claim 7, wherein one of the first spectroscopic element and the second spectroscopic element is a reflective concave diffraction element. 9.   8. The scanning display device optical system according to claim 7, wherein one of the first spectroscopic element and the second spectroscopic element is a transmissive diffraction element.   A first spectroscopic element that decomposes white light into light of a plurality of wavelengths, a DMD that is decomposed by the first spectroscopic element and is adjusted to a desired color for each of the light of a plurality of wavelengths, and light reflected by the DMD And a projection lens for projecting light that has passed through the second spectral element.   A first spectral element that decomposes white light into light of a plurality of wavelengths, a DMD that reflects and adjusts the light decomposed by the first spectral element for each wavelength of several nanometers or less, and a light that is reflected by the DMD are combined. And a projection lens for projecting the light that has passed through the second spectral element.   The scanning display device optical system according to claim 10, further comprising a concave mirror that further reflects the light reflected by the DMD.   The at least one of the said 1st spectroscopic element and the said 2nd spectroscopic element is planar, and the light beam which passes an element is parallel, The any one of Claim 1 thru | or 12 characterized by the above-mentioned. Scanning display device optical system.   14. The scanning display according to claim 1, wherein the synthesized wavelength or light is projected onto a mirror that rotates within a predetermined angle range, and an image is projected onto a screen. Equipment optics.   A scanning display device comprising the scanning display device optical system according to any one of claims 1 to 14.

Images