JP5765032B2 - Illumination device, projection device, and projection-type image display device - Google Patents

Description

  The present invention relates to an illumination device that illuminates an illuminated area with coherent light, a projection device that projects coherent light, and a projection-type image display device that displays an image using coherent light, and in particular, generation of speckle is inconspicuous. The present invention relates to a lighting device, a projection device, and a projection-type image display device that can be made to operate.

  Projection-type image display devices having a screen and a projection device that projects image light on the screen are widely used. In a typical projection-type image display device, an original two-dimensional image is generated by using a spatial light modulator such as a liquid crystal micro display or a DMD (Digital Micromirror Device), and the two-dimensional image is projected into an optical system. An image is displayed on the screen by enlarging and projecting on the screen using the system.

  Various types of projectors have been proposed, including commercially available products called “optical projectors”. In general optical projectors, a spatial light modulator such as a liquid crystal display is illuminated using a lighting device consisting of a white light source such as a high-pressure mercury lamp, and the resulting modulated image is projected onto a screen using a lens. Adopted. For example, in Patent Document 1 below, white light generated by an ultra-high pressure mercury lamp is divided into three primary color components of R, G, and B by a dichroic mirror, and these lights are guided to a spatial light modulator for each primary color. A technique is disclosed in which a generated modulated image for each primary color is synthesized by a cross dichroic prism and projected onto a screen.

  However, high-intensity discharge lamps such as high-pressure mercury lamps have a relatively short life, and when used in optical projectors or the like, it is necessary to frequently replace the lamps. Further, since it is necessary to use a relatively large optical system such as a dichroic mirror in order to extract the light of each primary color component, there is a problem that the entire apparatus becomes large.

  In order to cope with such a problem, a method using a coherent light source such as a laser has been proposed. For example, a semiconductor laser widely used in the industry has a very long life compared to a high-intensity discharge lamp such as a high-pressure mercury lamp. In addition, since the light source can generate light having a single wavelength, a spectroscopic device such as a dichroic mirror is not necessary, and the entire device can be reduced in size.

  On the other hand, a method using a coherent light source such as a laser beam has a new problem such as generation of speckle. A speckle is a speckled pattern that appears when a scattering surface is irradiated with laser light or other coherent light. When it appears on a screen, it is observed as speckled brightness irregularities (brightness irregularities). It becomes a factor having a physiological adverse effect on the person. The reason why speckles occur when coherent light is used is that coherent light reflected by each part of a scattering reflection surface such as a screen interferes with each other because of its extremely high coherence. . For example, in the following Non-Patent Document 1, detailed theoretical considerations regarding the generation of speckle are made.

  As described above, in the system using the coherent light source, a problem inherent to the generation of speckles occurs, and thus a technique for suppressing the generation of speckles has been proposed. For example, in Patent Document 2 below, the speckle is reduced by irradiating a scattering plate with laser light, guiding the scattered light obtained therefrom to a spatial light modulator, and rotating the scattering plate by a motor. Technology is disclosed.

JP 2004-264512 A Japanese Patent Laid-Open No. 6-208089

Speckle Phenomena in Optics, Joseph W. Goodman, Roberts & Co., 2006

  As described above, technologies for reducing speckles have been proposed in projection devices and projection-type video display devices using a coherent light source. However, the methods proposed so far effectively and sufficiently suppress speckles. I can't do it. For example, in the method disclosed in the above-mentioned Patent Document 2, laser light is irradiated on the scattering plate and scattered, and therefore, part of the laser light is wasted without contributing to video display at all. Moreover, although it is necessary to rotate a scattering plate for speckle reduction, such a mechanical rotation mechanism becomes a comparatively large apparatus, and also power consumption becomes large. Furthermore, even if the scattering plate is rotated, the position of the optical axis of the illumination light does not change, so that speckles visually recognized on the screen cannot be sufficiently suppressed.

  Speckle is not a problem specific to a projection device or a projection type image display device, but is a problem in various devices in which an illumination device that illuminates coherent light in an illuminated area. For example, a scanner that reads image information incorporates an illumination device that illuminates an object to be read. When speckle is generated by the light that illuminates the object to be read, the image information cannot be read accurately. In order to avoid such an inconvenience, a scanner using coherent light needs to perform special processing such as image correction.

  Incidentally, coherent light generated from a single light source is typically monochromatic light, as represented by laser light. Further, coherent light generated from a practical light source is limited to light of a specific wavelength (range). On the other hand, in many cases today, it is desirable to illuminate the illuminated area or display an image in a desired color that cannot be displayed with a single light source, or in multiple colors, typically full color. It is rare. Therefore, the illumination device, the projection device, and the projection display device that are actually developed can illuminate the illuminated region with a plurality of coherent lights having different wavelength ranges in order to correspond to various applications today, It is preferable that the present invention can be suitably applied to displaying an image using a plurality of coherent lights having different areas.

  It should be noted that the specific visibility of the human eye, that is, how the human eye perceives the brightness of the light changes according to the wavelength. For this reason, the speckle becomes easier to be visually recognized as the light having a wavelength range with higher specific visibility. Therefore, it is preferable that speckles can be effectively made inconspicuous in consideration of such points.

  The present invention has been made in consideration of the above points, and is an illuminating device that illuminates an illuminated area with a plurality of coherent lights having different wavelength ranges, and effectively makes speckles inconspicuous. An object of the present invention is to provide a lighting device that can be used, and to provide a projection device and a projection-type image display device including the lighting device.

A first lighting device according to the present invention comprises:
A hologram recording medium capable of diffracting a first coherent light in a first wavelength region and a second coherent light in a second wavelength region different from the first wavelength region;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device illuminates an area where the first coherent light is diffracted by the hologram recording medium and overlaps at least partially, and the hologram recording from the irradiation device The irradiation device and the hologram recording medium are arranged so that the second coherent light incident on each position of the medium illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially.
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. The angle is larger than the maximum angle formed by the two incident directions of the first coherent light incident on a certain point from various directions.
In such a first illumination device according to the present invention, the two incident directions of the second coherent light that are incident on the center point (position of the center of gravity) in the overlapping portion in the illuminated area from various directions. Is larger than the maximum angle formed by the two incident directions of the first coherent light incident on the central point (position of the center of gravity) in the overlapping portion in the illuminated area from various directions. It may be bigger.
In such a first lighting device according to the present invention, two incidents of the second coherent light that are incident from various directions on arbitrary points in the overlapping portion (illuminated region) in the illuminated region. The maximum angle formed by the direction is the maximum angle formed by the two incident directions of the first coherent light that is incident from various directions at any point in the overlapping portion (illuminated region) in the illuminated region. May be larger.
In such a first illumination device according to the present invention, the second coherent light incident on each position of the hologram recording medium from the irradiation device overlaps each other in a region illuminated by the first coherent light. The irradiation device and the hologram recording medium may be arranged so as to illuminate the light.
In the first illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region on the basis of the photopic standard relative luminous sensitivity. It may have specific visibility.

In the first lighting device according to the present invention,
The hologram recording medium can diffract third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region;
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation apparatus and the hologram recording so that the third coherent light incident on each position of the hologram recording medium from the irradiation apparatus illuminates a region that is diffracted by the hologram recording medium and at least partially overlaps each other. Medium is placed,
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. Greater than the maximum angle formed by the two incident directions of the third coherent light incident on a point from various directions;
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the first illumination device according to the present invention, the third coherent light incident on each position of the hologram recording medium from the irradiation device is illuminated by the first coherent light and the second coherent light, respectively. The irradiating device and the hologram recording medium may be arranged so as to illuminate overlapping portions in a region to be illuminated.

In the first illuminating device according to the present invention, a plurality of the hologram recording media are provided corresponding to coherent light in each wavelength region, and the plurality of hologram recording media are arranged on a plane.
The irradiation device includes: a light source mechanism that generates combined light obtained by combining a plurality of coherent lights having different wavelength ranges; and a traveling direction of the combined light from the light source mechanism, and the combined light is converted into the hologram A scanning device adapted to scan over a recording medium,
The irradiation device irradiates the combined light so as to scan a plurality of hologram recording media in which the combined light is arranged side by side along a linear scanning path,
The length of the scanning path of the combined light on the hologram recording medium corresponding to the second coherent light is the length of the combined light on the hologram recording medium corresponding to the first coherent light or all other coherent lights. It may be longer than the length of the scanning path.
In the first illumination device according to the present invention, the width of the hologram recording medium corresponding to the second coherent light along the direction parallel to the scanning path of the combined light is parallel to the scanning path of the combined light. It may be longer than the width of the hologram recording medium corresponding to the first coherent light or all other coherent light along a certain direction.

In the first lighting device according to the present invention,
The overlapping part in the region illuminated by the first coherent light and the overlapping part in the region illuminated by the second coherent light overlap each other,
A plurality of hologram recording media are provided corresponding to coherent light in each wavelength region,
The hologram recording medium corresponding to the second coherent light is arranged closer to the overlapping portion in the illuminated region than the hologram recording medium corresponding to the first coherent light or all other coherent lights. It may be.
In the first lighting device according to the present invention,
The irradiation device scans the hologram recording medium by changing a traveling direction of the coherent light from the plurality of light sources respectively generating the plurality of coherent lights having different wavelength ranges and the plurality of light sources. And a scanning device to
A plurality of coherent lights having different wavelength ranges may be incident on the same scanning device from different directions, and the traveling directions may be changed in different directions.

In the first illumination device according to the present invention, the speed at which the second coherent light scans on the hologram recording medium is such that the first coherent light or all other coherent light scans on the hologram recording medium. It may be faster than the speed.
In such a first illumination device according to the present invention, each coherent light periodically scans a certain scanning path on the hologram recording medium, and the certain scanning on the hologram recording medium scanned by each coherent. The lengths of the paths may be the same.

In the first lighting device according to the present invention,
Each coherent light periodically scans a certain scanning path on the hologram recording medium,
The length of the fixed scanning path on the hologram recording medium scanned by the second coherent is the first coherent light or all other coherent light) on the hologram recording medium scanned by the coherent It may be longer than a certain scanning path length.

In the first lighting device according to the present invention,
The irradiation device is provided corresponding to each of a plurality of light sources that respectively generate a plurality of coherent lights having different wavelength ranges, and a coherent light from each light source, and changes a traveling direction of the coherent light from the corresponding light source. A plurality of scanning devices for allowing the coherent light to scan on the hologram recording medium,
Each of the plurality of scanning devices has a corresponding coherent light that vibrates on the hologram recording medium at a constant first direction frequency along the first direction and along a second direction that intersects the first direction. However, the traveling direction of the corresponding coherent light is changed so as to vibrate at a constant second direction frequency equal to or lower than the first direction frequency,
The value of the ratio of the first direction frequency to the second direction frequency of the scanning device that changes the traveling direction of the second coherent light is the traveling direction of the first coherent light or all other coherent light. It may be larger than the value of the ratio of the first direction frequency to the second direction frequency of the scanning device that changes.
In such a first illumination device according to the present invention, the lengths of each coherent light scanned along the first direction on the hologram recording medium are the same, and each coherent light is the hologram recording medium. The lengths of scanning along the second direction above may be the same.
In the first lighting apparatus according to the present invention, the second direction frequencies of the scanning devices that change the traveling direction of each coherent light may be the same.

A second lighting device according to the present invention comprises:
The image of the scattering plate can be reproduced using the first coherent light in the first wavelength region as the reproduction illumination light, and the second coherent light in the second wavelength region different from the first wavelength region is used as the reproduction illumination light. A hologram recording medium capable of reproducing
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device respectively reproduces an image, and the second coherent light incident on each position of the hologram recording medium from the irradiation device. The irradiation device and the hologram recording medium are arranged so that each of the lights overlaps to reproduce an image,
The maximum angle formed by the two incident directions of the second coherent light that enters the point where the image is reproduced from various directions is different in the direction where the image is reproduced. Greater than the maximum angle formed by the two incident directions of the first coherent light incident from.
In the second illuminating device according to the present invention as described above, the maximum made by the two incident directions of the second coherent light entering the central point (center of gravity) of the reproduced image from various directions. The angle may be larger than the maximum angle formed by the two incident directions of the first coherent light incident on the center point (the position of the center of gravity) of the reproduced image from various directions.
In the second illuminating device according to the present invention, the maximum made by the two incident directions of the second coherent light entering the arbitrary point of the reproduced image (illuminated area) from various directions. May be larger than the maximum angle formed by the two incident directions of the first coherent light incident on an arbitrary point of the reproduced image (illuminated area) from various directions.
In the second illumination device according to the present invention as described above, the second coherent light incident on each position of the hologram recording medium from the irradiation device overlaps with an image reproduced by the first coherent light. The irradiation device and the hologram recording medium may be arranged so as to reproduce an image in a superimposed manner.
In such a second illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region with reference to photopic standard relative luminous sensitivity. It may have specific visibility.

In a second lighting device according to the present invention,
The hologram recording medium can reproduce an image of a scattering plate using third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region as reproduction illumination light,
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation device and the hologram recording medium are arranged so that the third coherent light incident on each position of the hologram recording medium from the irradiation device respectively reproduces an image,
The maximum angle formed by the two incident directions of the second coherent light that enters the point where the image is reproduced from various directions is different in the direction where the image is reproduced. Greater than the maximum angle formed by the two incident directions of the third coherent light incident from
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the second illumination device according to the present invention, the third coherent light incident on each position of the hologram recording medium from the irradiation device is reproduced by the first coherent light and the second coherent light, respectively. The irradiation device and the hologram recording medium may be arranged so as to reproduce the image superimposed on a position overlapping with the image to be recorded.

In the second illuminating device according to the present invention, a plurality of the hologram recording media are provided corresponding to coherent light in each wavelength region, and the plurality of hologram recording media are arranged on a certain plane,
The irradiation device includes: a light source mechanism that generates combined light obtained by combining a plurality of coherent lights having different wavelength ranges; and a traveling direction of the combined light from the light source mechanism, and the combined light is converted into the hologram A scanning device adapted to scan over a recording medium,
The irradiation device irradiates the combined light so as to scan a plurality of hologram recording media in which the combined light is arranged side by side along a linear scanning path,
The length of the scanning path of the combined light on the hologram recording medium corresponding to the second coherent light is the length of the combined light on the hologram recording medium corresponding to the first coherent light or all other coherent lights. It may be longer than the length of the scanning path.
In such a second illumination device according to the present invention, the width of the hologram recording medium corresponding to the second coherent light along a direction parallel to the scanning path of the combined light is parallel to the scanning path of the combined light. It may be longer than the width of the hologram recording medium corresponding to the first coherent light or all other coherent light along a certain direction.

In a second lighting device according to the present invention,
The image reproduced by the first coherent light and the image reproduced by the second coherent light are reproduced at overlapping positions,
A plurality of hologram recording media are provided corresponding to coherent light in each wavelength region,
The hologram recording medium corresponding to the second coherent light is arranged closer to the position where the image is reproduced than the hologram recording medium corresponding to the first coherent light or all other coherent lights. Also good.
In the second lighting device according to the present invention,
The irradiation device scans the hologram recording medium by changing a traveling direction of the coherent light from the plurality of light sources respectively generating the plurality of coherent lights having different wavelength ranges and the plurality of light sources. And a scanning device to
A plurality of coherent lights having different wavelength ranges may be incident on the same scanning device from different directions, and the traveling directions may be changed in different directions.

In the second illumination device according to the present invention, the speed at which the second coherent light scans on the hologram recording medium is such that the first coherent light or all other coherent light scans on the hologram recording medium. It may be faster than the speed.
In such a second illumination device according to the present invention, each coherent light periodically scans a certain scanning path on the hologram recording medium, and the certain scanning on the hologram recording medium scanned by each coherent. The lengths of the paths may be the same.

In a second lighting device according to the present invention,
Each coherent light periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent is the constant scanning on the hologram recording medium scanned by the first coherent light or all other coherent light. It may be longer than the length of the route.

In the second lighting device according to the present invention,
The irradiation device is provided corresponding to each of a plurality of light sources that respectively generate a plurality of coherent lights having different wavelength ranges, and a coherent light from each light source, and changes a traveling direction of the coherent light from the corresponding light source. A plurality of scanning devices for allowing the coherent light to scan on the hologram recording medium,
Each of the plurality of scanning devices has a corresponding coherent light that vibrates on the hologram recording medium at a constant first direction frequency along the first direction and along a second direction that intersects the first direction. However, the traveling direction of the corresponding coherent light is changed so as to vibrate at a constant second direction frequency equal to or lower than the first direction frequency,
The value of the ratio of the first direction frequency to the second direction frequency of the scanning device that changes the traveling direction of the second coherent light is the traveling direction of the first coherent light or all other coherent light. It may be larger than the value of the ratio of the first direction frequency to the second direction frequency of the scanning device that changes.
In such a first illumination device according to the present invention, the lengths of each coherent light scanned along the first direction on the hologram recording medium are the same, and each coherent light is the hologram recording medium. The lengths of scanning along the second direction above may be the same.
In the second illumination apparatus according to the present invention, the second direction frequencies of the scanning devices that change the traveling direction of each coherent light may be the same.

A third lighting device according to the present invention comprises:
A hologram recording medium capable of diffracting a first coherent light in a first wavelength region and a second coherent light in a second wavelength region different from the first wavelength region;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device illuminates an area where the first coherent light is diffracted by the hologram recording medium and overlaps at least partially, and the hologram recording from the irradiation device The irradiation device and the hologram recording medium are arranged so that the second coherent light incident on each position of the medium illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially.
The speed at which the second coherent light scans on the hologram recording medium is faster than the speed at which the first coherent light scans on the hologram recording medium.
In such a third illumination device according to the present invention, the second coherent light incident on each position of the hologram recording medium from the irradiation device overlaps each other in a region illuminated by the first coherent light. The irradiation device and the hologram recording medium may be arranged so as to illuminate the light.
In such a third illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region with reference to photopic standard relative luminous sensitivity. It may have specific visibility.

In a third lighting device according to the present invention,
The hologram recording medium can diffract third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region;
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation apparatus and the hologram recording so that the third coherent light incident on each position of the hologram recording medium from the irradiation apparatus illuminates a region that is diffracted by the hologram recording medium and at least partially overlaps each other. Medium is placed,
The speed at which the second coherent light scans on the hologram recording medium is faster than the speed at which the third coherent light scans on the hologram recording medium,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the third illumination device according to the present invention as described above, the third coherent light incident on each position of the hologram recording medium from the irradiation device is illuminated by the first coherent light and the second coherent light, respectively. The irradiating device and the hologram recording medium may be arranged so as to illuminate the overlapping portions in the region to be illuminated.

  In the third illuminating device according to the present invention as described above, it is made by two incident directions of each coherent light that enters from a variety of directions to a certain point in an overlapping area (illuminated area) in the illuminated area. The maximum angle may be the same among the plurality of coherent lights.

A fourth lighting device according to the present invention includes:
The image of the scattering plate can be reproduced using the first coherent light in the first wavelength region as the reproduction illumination light, and the second coherent light in the second wavelength region different from the first wavelength region is used as the reproduction illumination light. A hologram recording medium capable of reproducing
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device respectively reproduces an image, and the second coherent light incident on each position of the hologram recording medium from the irradiation device. The irradiation device and the hologram recording medium are arranged so that each of the lights overlaps to reproduce an image,
The speed at which the second coherent light scans on the hologram recording medium is faster than the speed at which the first coherent light scans on the hologram recording medium.
In the fourth illumination device according to the present invention as described above, the second coherent light incident on each position of the hologram recording medium from the irradiation device overlaps with an image reproduced by the first coherent light. The irradiation device and the hologram recording medium may be arranged so as to reproduce an image in a superimposed manner.
In the fourth illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region on the basis of the photopic standard relative luminous sensitivity. It may have specific visibility.

In a fourth lighting device according to the present invention,
The hologram recording medium can reproduce an image of a scattering plate using third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region as reproduction illumination light,
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation device and the hologram recording medium are arranged so that the third coherent light incident on each position of the hologram recording medium from the irradiation device respectively reproduces an image,
The speed at which the second coherent light scans on the hologram recording medium is faster than the speed at which the third coherent light scans on the hologram recording medium,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the fourth illumination device according to the present invention, the third coherent light incident on each position of the hologram recording medium from the irradiation device is reproduced by the first coherent light and the second coherent light, respectively. The irradiation device and the hologram recording medium may be arranged so as to reproduce the image superimposed on a position overlapping with the image to be recorded.

  In the fourth illuminating device according to the present invention as described above, the maximum made by the two incident directions of each coherent light coming from various directions to one point where the image is reproduced (illuminated area). The angle may be the same among the plurality of coherent lights.

A fifth lighting device according to the present invention includes:
A hologram recording medium capable of diffracting a first coherent light in a first wavelength region and a second coherent light in a second wavelength region different from the first wavelength region;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device illuminates an area where the first coherent light is diffracted by the hologram recording medium and overlaps at least partially, and the hologram recording from the irradiation device The irradiation device and the hologram recording medium are arranged so that the second coherent light incident on each position of the medium illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially.
Each of the plurality of coherent lights periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent is longer than the length of the constant scanning path on the hologram recording medium scanned by the first coherent.
In the fifth illuminating device according to the present invention, the second coherent light incident on each position of the hologram recording medium from the irradiating device overlaps each other in a region illuminated by the first coherent light. The irradiation device and the hologram recording medium may be arranged so as to illuminate the light.
In the fifth illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region on the basis of photopic standard relative luminous sensitivity. It may have specific visibility.

In a fifth lighting device according to the present invention,
The hologram recording medium can diffract third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region;
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation apparatus and the hologram recording so that the third coherent light incident on each position of the hologram recording medium from the irradiation apparatus illuminates a region that is diffracted by the hologram recording medium and at least partially overlaps each other. Medium is placed,
The third coherent light periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent is longer than the length of the constant scanning path on the hologram recording medium scanned by the third coherent,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the fifth illumination device according to the present invention, the third coherent light incident on each position of the hologram recording medium from the irradiation device is illuminated with the first coherent light and the second coherent light, respectively. The irradiating device and the hologram recording medium may be arranged so as to illuminate the overlapping portions in the region to be illuminated.

  In the fifth illuminating device according to the present invention, the maximum made by the two incident directions of each coherent light coming from various directions into a certain point in the overlapping area (illuminated area) in the illuminated area. The angle may be the same among the plurality of coherent lights.

A sixth lighting device according to the present invention includes:
The image of the scattering plate can be reproduced using the first coherent light in the first wavelength region as the reproduction illumination light, and the second coherent light in the second wavelength region different from the first wavelength region is used as the reproduction illumination light. A hologram recording medium capable of reproducing
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device respectively reproduces an image, and the second coherent light incident on each position of the hologram recording medium from the irradiation device. The irradiation device and the hologram recording medium are arranged so that each of the lights overlaps to reproduce an image,
Each of the plurality of coherent lights periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent is longer than the length of the constant scanning path on the hologram recording medium scanned by the first coherent.
In the sixth illuminating device according to the present invention, the second coherent light incident on each position of the hologram recording medium from the irradiating device overlaps with an image reproduced by the first coherent light. The irradiation device and the hologram recording medium may be arranged so as to reproduce an image in a superimposed manner.
In the sixth illuminating device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region with reference to photopic standard relative luminous sensitivity. It may have specific visibility.

In a sixth lighting device according to the present invention,
The hologram recording medium can reproduce an image of a scattering plate using third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region as reproduction illumination light,
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation device and the hologram recording medium are arranged so that the third coherent light incident on each position of the hologram recording medium from the irradiation device respectively reproduces an image,
The third coherent light periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent light is longer than the length of the constant scanning path on the hologram recording medium scanned by the third coherent light,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the sixth illumination device according to the present invention, the third coherent light incident on each position of the hologram recording medium from the irradiation device is reproduced by the first coherent light and the second coherent light, respectively. The irradiation device and the hologram recording medium may be arranged so as to reproduce the image superimposed on a position overlapping with the image to be recorded.

  In the sixth illuminating device according to the present invention, the maximum angle formed by the two incident directions of each coherent light that comes to be incident on a certain point where the image is reproduced from various directions is the plurality of coherent lights. May be the same.

In any one of the first to sixth illumination devices according to the present invention, a plurality of the hologram recording media may be provided corresponding to the coherent lights in the respective wavelength ranges.
In such an illuminating device according to the present invention, the plurality of hologram recording media provided corresponding to the coherent light of each wavelength region may be arranged on a certain plane, or A plurality of hologram recording media provided corresponding to each of the coherent lights may be arranged in an overlapping manner.

In any of the first to sixth lighting devices according to the present invention,
The irradiation device includes: a light source mechanism that generates combined light obtained by combining a plurality of coherent lights having different wavelength ranges; and a traveling direction of the combined light from the light source mechanism, and the combined light is converted into the hologram A scanning device adapted to scan over a recording medium,
The light source mechanism may include a plurality of light sources that respectively generate coherent light in each wavelength region, and a combining device that combines the coherent lights from the plurality of light sources.

  In any one of the first to sixth illumination devices according to the present invention, the irradiation device corresponds to a plurality of light sources that respectively generate a plurality of coherent lights having different wavelength ranges, and a coherent light from each light source. And a plurality of scanning devices that change the traveling direction of the coherent light from the corresponding light source so that the coherent light scans the hologram recording medium.

In any of the first to sixth lighting devices according to the present invention,
The irradiation device scans the hologram recording medium by changing a traveling direction of the coherent light from the plurality of light sources respectively generating the plurality of coherent lights having different wavelength ranges and the plurality of light sources. And a scanning device to
A plurality of coherent lights having different wavelength ranges may be incident on the same scanning device from different directions, and the traveling directions may be changed in different directions.

  In any one of the first to sixth lighting devices according to the present invention, the time when each light source is generating coherent light may not be the same.

A seventh lighting device according to the present invention includes:
A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiating device illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other, and The irradiation apparatus and the light diffusing element are configured such that the second coherent light incident on each position of the light diffusing element is changed in a traveling direction by the light diffusing element and illuminates regions overlapping at least in part. Is placed,
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. The angle is larger than the maximum angle formed by the two incident directions of the first coherent light incident on a certain point from various directions.
In the seventh illumination device according to the present invention, the second coherent light incident on each position of the light diffusing element from the irradiation device is changed in traveling direction by the light diffusing element, and The irradiating device and the light diffusing element may be arranged so as to illuminate overlapping portions in a region illuminated by the first coherent light.
In such a seventh illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region on the basis of the photopic standard relative luminous sensitivity. It may have specific visibility.

In a seventh lighting device according to the present invention,
The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The irradiation apparatus so that the third coherent light incident on each position of the light diffusing element from the irradiation apparatus illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other. And the light diffusing element is disposed,
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. Greater than the maximum angle formed by the two incident directions of the third coherent light incident on a point from various directions;
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the seventh illumination device according to the present invention, the traveling direction of the third coherent light incident on each position of the light diffusing element from the irradiation device is changed by the light diffusing element. The irradiating device and the light diffusing element may be arranged so as to illuminate overlapping portions in a region illuminated by the first coherent light and the second coherent light.

An eighth lighting device according to the present invention includes:
A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiation device changes the traveling direction by the light diffusing element to illuminate the illuminated area, and the light diffusing element from the irradiation device. The irradiation device and the light diffusing element are arranged such that the second coherent light incident on each of the positions of the second coherent light is changed in the traveling direction by the light diffusing element and illuminates the illuminated area, respectively.
The maximum angle formed by the two incident directions of the second coherent light that is incident on a certain point of the illuminated region from various directions is the first angle incident on the certain point of the illuminated region from various directions. It is greater than the maximum angle made by the two incident directions of coherent light.
In the eighth illumination device according to the present invention, the second coherent light incident on each position of the light diffusing element from the irradiation device is changed in traveling direction by the light diffusing element, and The irradiation apparatus and the light diffusing element may be arranged so as to illuminate the same illuminated area as the illuminated area illuminated by the first coherent light.
In the eighth illuminating device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region with reference to photopic standard relative luminous sensitivity. It may have specific visibility.

In an eighth lighting device according to the present invention,
The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The third coherent light incident on each position of the light diffusing element from the irradiation apparatus is changed in the traveling direction by the light diffusing element to illuminate the illuminated region, and the irradiation apparatus and the light A diffusing element is arranged,
The maximum angle formed by the two incident directions of the second coherent light that enters a certain point of the illuminated area from various directions is the third angle incident on the certain point of the illuminated area from various directions. Greater than the maximum angle formed by the two incident directions of coherent light,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the eighth illumination device according to the present invention, the traveling direction of the third coherent light incident on each position of the light diffusing element from the irradiation device is changed by the light diffusing element. The irradiation device and the light diffusing element may be arranged so as to illuminate an illuminated area that is the same as the illuminated area illuminated by the first coherent light and the second coherent light.

A ninth lighting device according to the present invention includes:
A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiating device illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other, and The irradiation apparatus and the light diffusing element are configured such that the second coherent light incident on each position of the light diffusing element is changed in a traveling direction by the light diffusing element and illuminates regions overlapping at least in part. Is placed,
The speed at which the second coherent light scans on the light diffusing element is faster than the speed at which the first coherent light scans on the light diffusing element.
In the ninth illumination device according to the present invention, the second coherent light incident on each position of the light diffusing element from the irradiation device is changed in traveling direction by the light diffusing element, and The irradiating device and the light diffusing element may be arranged so as to illuminate overlapping portions in a region illuminated by the first coherent light.
In the ninth illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region on the basis of the photopic standard relative luminous sensitivity. It may have specific visibility.

In a ninth lighting device according to the present invention,
The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The irradiation apparatus so that the third coherent light incident on each position of the light diffusing element from the irradiation apparatus illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other. And the light diffusing element is disposed,
A speed at which the second coherent light scans on the light diffusing element is faster than a speed at which the third coherent light scans on the light diffusing element;
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the ninth illuminating device according to the present invention, the traveling direction of the third coherent light incident on each position of the light diffusing element from the irradiation device is changed by the light diffusing element, The irradiating device and the light diffusing element may be arranged so as to illuminate overlapping portions in a region illuminated by the first coherent light and the second coherent light.

  In the ninth illuminating device according to the present invention, the maximum angle formed by the two incident directions of each coherent light coming from various directions at a certain point in the overlapping portion in the illuminated region is The plurality of coherent lights may be the same.

A tenth lighting device according to the present invention comprises:
A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiation device changes the traveling direction by the light diffusing element to illuminate the illuminated area, and the light diffusing element from the irradiation device. The irradiation device and the light diffusing element are arranged such that the second coherent light incident on each of the positions of the second coherent light is changed in the traveling direction by the light diffusing element and illuminates the illuminated area, respectively.
The speed at which the second coherent light scans on the light diffusing element is faster than the speed at which the first coherent light scans on the light diffusing element.
In the tenth illumination device according to the present invention, the second coherent light incident on each position of the light diffusing element from the irradiation device is changed in traveling direction by the light diffusing element, and The irradiation device and the light diffusing element may be arranged so as to illuminate the same illuminated area as the illuminated area illuminated by the first coherent light.
In the tenth illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region on the basis of photopic standard relative luminous sensitivity. It may have specific visibility.

In a tenth lighting device according to the present invention,
The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The third coherent light incident on each position of the light diffusing element from the irradiation apparatus is changed in the traveling direction by the light diffusing element to illuminate the illuminated region, and the irradiation apparatus and the light A diffusing element is arranged,
A speed at which the second coherent light scans on the light diffusing element is faster than a speed at which the third coherent light scans on the light diffusing element;
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the tenth illumination device according to the present invention, the traveling direction of the third coherent light incident on each position of the light diffusing element from the irradiation device is changed by the light diffusing element, The irradiation device and the light diffusing element may be arranged so as to illuminate an illuminated area that is the same as the illuminated area illuminated by the first coherent light and the second coherent light.

  In the tenth illuminating device according to the present invention, the maximum angle formed by the two incident directions of each coherent light that is incident on a certain point of the illuminated region from various directions is the plurality of coherent lights. May be the same between.

The eleventh lighting device according to the present invention is
A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiating device illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other, and The irradiation apparatus and the light diffusing element are configured such that the second coherent light incident on each position of the light diffusing element is changed in a traveling direction by the light diffusing element and illuminates regions overlapping at least in part. Is placed,
Each of the plurality of coherent lights periodically scans a certain scanning path on the light diffusing element,
The length of the constant scanning path on the light diffusing element scanned by the second coherent light is longer than the length of the constant scanning path on the light diffusing element scanned by the first coherent light.
In the eleventh illumination device according to the present invention, the traveling direction of the second coherent light incident on each position of the light diffusing element from the irradiation device is changed by the light diffusing element. The irradiating device and the light diffusing element may be arranged so as to illuminate overlapping portions in a region illuminated by the first coherent light.
In the eleventh illuminating device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region with reference to photopic standard relative luminous sensitivity. It may have specific visibility.

In an eleventh illumination device according to the present invention,
The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The irradiation apparatus so that the third coherent light incident on each position of the light diffusing element from the irradiation apparatus illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other. And the light diffusing element is disposed,
The third coherent light periodically scans a certain scanning path on the light diffusing element,
The length of the constant scanning path on the light diffusing element scanned by the second coherent light is longer than the length of the constant scanning path on the light diffusing element scanned by the third coherent light,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In the eleventh illuminating device according to the present invention, the traveling direction of the third coherent light incident on each position of the light diffusing element from the irradiation device is changed by the light diffusing element. The irradiating device and the light diffusing element may be arranged so as to illuminate overlapping portions in a region illuminated by the first coherent light and the second coherent light.

  In the eleventh illuminating device according to the present invention, the maximum angle formed by the two incident directions of each coherent light coming from various directions at a certain point in the overlapping portion in the illuminated region is The plurality of coherent lights may be the same.

A twelfth lighting device according to the present invention includes:
A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiation device changes the traveling direction by the light diffusing element to illuminate the illuminated area, and the light diffusing element from the irradiation device. The irradiation device and the light diffusing element are arranged such that the second coherent light incident on each of the positions of the second coherent light is changed in the traveling direction by the light diffusing element and illuminates the illuminated area, respectively.
Each of the plurality of coherent lights periodically scans a certain scanning path on the light diffusing element,
The length of the constant scanning path on the light diffusing element scanned by the second coherent light is longer than the length of the constant scanning path on the light diffusing element scanned by the first coherent light.
In the twelfth illuminating device according to the present invention, the second coherent light incident on each position of the light diffusing element from the irradiation device has its traveling direction changed by the light diffusing element, and The irradiation device and the light diffusing element may be arranged so as to illuminate the same illuminated area as the illuminated area illuminated by the first coherent light.
In the twelfth illumination device according to the present invention, the second coherent light in the second wavelength region is higher than the first coherent light in the first wavelength region on the basis of the photopic standard relative luminous sensitivity. It may have specific visibility.

In a twelfth lighting device according to the present invention,
The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The third coherent light incident on each position of the light diffusing element from the irradiation apparatus is changed in the traveling direction by the light diffusing element to illuminate the illuminated region, and the irradiation apparatus and the light A diffusing element is arranged,
The third coherent light periodically scans a certain scanning path on the light diffusing element,
The length of the constant scanning path on the light diffusing element scanned by the second coherent light is longer than the length of the constant scanning path on the light diffusing element scanned by the third coherent light,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. You may respond | correspond to a 3rd primary color component in the long wavelength side rather than a wavelength range.
In such a twelfth illumination device according to the present invention, the third coherent light incident on each position of the light diffusing element from the irradiation device is changed in traveling direction by the light diffusing element, and The irradiation device and the light diffusing element may be arranged so as to illuminate an illuminated area that is the same as the illuminated area illuminated by the first coherent light and the second coherent light.

  In such a twelfth illuminating device according to the present invention, the maximum angle formed by the two incident directions of each coherent light incident on a certain point of the illuminated region from various directions is the plurality of coherent lights. May be the same between.

In any of the seventh to twelfth illumination devices according to the present invention, a plurality of the light diffusing elements may be provided corresponding to the coherent lights in the respective wavelength ranges.
In any of the seventh to twelfth illumination devices according to the present invention, the plurality of light diffusing elements provided corresponding to the coherent lights in the respective wavelength ranges may be arranged on a certain plane. Good.

  In any of the seventh to twelfth illuminating devices according to the present invention, the irradiating device generates a combined light formed by combining a plurality of coherent lights having different wavelength ranges, and the light source mechanism supplies the combined light. A scanning device that changes the traveling direction of the combined light so that the combined light scans the light diffusing element, and the light source mechanism generates a plurality of light sources each generating coherent light in each wavelength region And a synthesizing device that synthesizes coherent light from the plurality of light sources.

  In any one of the seventh to twelfth illumination devices according to the present invention, the irradiation device corresponds to a plurality of light sources that respectively generate a plurality of coherent lights having different wavelength ranges, and a coherent light from each light source. And a plurality of scanning devices that change the traveling direction of the coherent light from the corresponding light source so that the coherent light scans the hologram recording medium.

  In any of the seventh to twelfth illuminating devices according to the present invention, the irradiation device includes a plurality of light sources that respectively generate a plurality of coherent lights having different wavelength ranges, and a traveling direction of the coherent light from the plurality of light sources. A plurality of coherent lights having different wavelength ranges are incident on the same scanning device from different directions. The traveling direction may be changed in different directions.

  In any of the seventh to twelfth illumination devices according to the present invention, the time when each light source is generating coherent light may not be the same.

  In any of the seventh to twelfth illumination devices according to the present invention, the light diffusing element may be a lens array.

A first projection device according to the present invention comprises:
The lighting device according to any one of the first, third and fifth aspects of the present invention described above;
A spatial light modulator disposed at a position illuminated by the coherent light that is incident and diffracted from each position of the hologram recording medium from the irradiation device.

The second projection device according to the present invention is:
The lighting device according to any one of the seventh, ninth, and eleventh aspects of the present invention described above,
A spatial light modulator disposed at a position illuminated by the coherent light that is incident on each position of the light diffusing element from the irradiation device and whose traveling direction is changed.

The third projection device according to the present invention is:
Any of the second, fourth and sixth lighting devices according to the invention described above;
A spatial light modulator disposed at a position overlapping an image reproduced by the coherent light incident on each position of the hologram recording medium from the irradiation device.

A fourth projection device according to the present invention includes:
Any of the eighth, tenth and twelfth lighting devices according to the invention as described above;
A spatial light modulator disposed at a position overlapping the illuminated area and illuminated by the illumination device.

  Any one of the first to fourth projection apparatuses according to the present invention may further include a projection optical system that projects a modulated image obtained on the spatial light modulator onto a screen.

In the first projection device according to the present invention,
The overlapping portions in the region illuminated by the coherent light diffracted by the hologram recording medium are located at different positions between the plurality of coherent lights,
A plurality of the spatial light modulators are provided corresponding to each of the plurality of coherent lights,
Each spatial light modulator is arranged so as to overlap with an overlapping part in the region illuminated by the corresponding coherent light,
A synthetic projection optical system that synthesizes and projects the modulated image obtained on each spatial light modulator may be further provided.

In a second projection device according to the present invention,
The overlapping portions in the region illuminated by the coherent light whose traveling direction is changed by the light diffusing element are located at different positions between the plurality of coherent lights,
A plurality of the spatial light modulators are provided corresponding to each of the plurality of coherent lights,
Each spatial light modulator is arranged so as to overlap with an overlapping part in the region illuminated by the corresponding coherent light,
A synthetic projection optical system that synthesizes and projects the modulated image obtained on each spatial light modulator may be further provided.

In a third projection device according to the present invention,
The plurality of coherent lights reproduce images at different positions;
A plurality of the spatial light modulators are provided corresponding to positions overlapping with images reproduced by each coherent light,
A synthetic projection optical system that synthesizes and projects the modulated image obtained on each spatial light modulator may be further provided.

In a fourth projection apparatus according to the present invention,
The plurality of coherent lights illuminate illuminated areas at different positions;
A plurality of the spatial light modulators are provided corresponding to the positions overlapping the illuminated area illuminated by each coherent light,
A synthetic projection optical system that synthesizes and projects the modulated image obtained on each spatial light modulator may be further provided.

A first projection display apparatus according to the present invention is:
Any one of the first to fourth projection devices according to the present invention described above;
And a screen on which the modulated image obtained on the spatial light modulator is projected.

A second projection type video display device according to the present invention is:
The lighting device according to any one of the first, third and fifth aspects of the present invention described above;
A screen illuminated by the coherent light incident on and diffracted from each position of the hologram recording medium from the irradiation device,
The overlapping portions in the region illuminated by the coherent light diffracted by the hologram recording medium overlap each other between the plurality of coherent lights,
The screen is arranged so as to overlap with an overlapping portion in a region illuminated by the plurality of coherent lights.

A third projection type image display device according to the present invention includes:
The lighting device according to any one of the seventh, ninth, and eleventh aspects of the present invention described above,
A screen illuminated by the coherent light that is incident on each position of the light diffusing element from the irradiation device and whose traveling direction is changed, and
The overlapping portions in the region illuminated by the coherent light whose traveling direction is changed by the light diffusing element overlap each other among the plurality of coherent lights,
The screen is arranged so as to overlap with an overlapping portion in a region illuminated by the plurality of coherent lights.

A fourth projection display apparatus according to the present invention is:
Any of the second, fourth and sixth illumination devices according to the present invention described above, wherein the illumination device reproduces an image at a position where the plurality of coherent lights overlap each other;
A screen disposed at a position overlapping an image reproduced by the coherent light incident on each position of the hologram recording medium from the irradiation device.

A fifth projection display apparatus according to the present invention is
Any of the above-described eighth, tenth and twelfth illumination devices according to the present invention, wherein the plurality of coherent lights illuminate an illuminated region in the same position, and
And a screen disposed at a position overlapping the illuminated area.

  ADVANTAGE OF THE INVENTION According to this invention, the speckle on the to-be-illuminated area | region or the surface which projects an image | video can be made effectively inconspicuous.

FIG. 1 is a diagram for explaining a basic form of an embodiment according to the present invention, and shows a schematic configuration of a lighting device, a projection apparatus, and a projection type video display apparatus as one specific example of the basic form. FIG. FIG. 2 is a diagram illustrating the illumination device illustrated in FIG. 1. FIG. 3 is a diagram for explaining an exposure method for producing a hologram recording medium that forms an optical element of the illumination device of FIG. FIG. 4 is a diagram for explaining the operation of the hologram recording medium manufactured through the exposure method of FIG. FIG. 5 is a perspective view for explaining the operation of the lighting apparatus shown in FIG. FIG. 6 is a diagram for explaining a modification of the optical element, and is a plan view showing the optical element together with a corresponding illuminated region. FIG. 7 is a diagram for explaining another modification of the optical element, and is a plan view showing the optical element together with a corresponding illuminated region. FIG. 8 is a diagram corresponding to FIG. 5, and is a perspective view for explaining a modification of the lighting device and its operation. FIG. 9 is a diagram corresponding to FIG. 2, and is a perspective view for explaining another modification of the lighting device and its operation. FIG. 10 is a diagram for explaining an application form to which the basic form of one embodiment according to the present invention is applied, and is a lighting device, a projection apparatus, and a projection type video display apparatus as specific examples of the application form. It is a figure which shows schematic structure of these. FIG. 11 is a plan view showing the optical element of FIG. FIG. 12 is a graph showing the photopic standard relative luminous sensitivity defined by the CIE (Commission internationale de l'eclairage). FIG. 13 is a diagram illustrating a schematic configuration of an illumination device, a projection device, and a projection type video display device as another example of the application form. FIG. 14 is a diagram illustrating a schematic configuration of an illumination device, a projection device, and a projection type video display device as still another example of the application mode. FIG. 15 is a perspective view showing an irradiation apparatus that can be applied to an application form. FIG. 16 is a diagram illustrating a schematic configuration of an illumination device, a projection device, and a projection type video display device as still another example of the application mode. FIG. 17 is a diagram illustrating a schematic configuration of an illumination device, a projection device, and a projection type video display device as still another example of the application form.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product.

  The illumination device, the projection device, and the projection-type image display device according to an embodiment of the present invention have a configuration that can effectively prevent speckle as a basic configuration. Furthermore, the illumination device, the projection device, and the projection-type image display device according to an embodiment of the present invention have a configuration in which a basic configuration that can effectively prevent speckle is applied, and the wavelength ranges are mutually different. It also includes a configuration that enables handling of a plurality of different coherent lights.

  In the following description, first, referring to the projection type video display device including the illumination device and the projection device illustrated in FIGS. 1 to 9, a configuration for making speckles inconspicuous can be achieved based on the configuration. The operational effects and the modification of the configuration will be described as basic forms. Next, the configuration applying the basic form, the configuration that enables the handling of a plurality of coherent lights having different wavelength ranges, the operational effects that can be achieved based on the configuration, and the modification of the configuration, This will be described as an applied form.

<Basic form>
[Configuration of basic form]
First, the configuration of a projection-type image display device that includes an illumination device that projects coherent light and a projection device and can make speckles inconspicuous will be described mainly with reference to FIGS.

  A projection video display device 10 shown in FIG. 1 includes a screen 15 and a projection device 20 that projects video light including coherent light. The projection device 20 includes an illuminating device 40 that illuminates the illuminated region LZ located on the virtual plane with coherent light, and a spatial light modulator that is disposed at a position overlapping the illuminated region LZ and that is illuminated with the coherent light by the illuminating device 40. 30 and a projection optical system 25 that projects the coherent light from the spatial light modulator 30 onto the screen 15.

  As the spatial light modulator 30, for example, a transmissive liquid crystal microdisplay can be used. In this case, the spatial light modulator 30 illuminated in a planar shape by the illumination device 40 selects and transmits coherent light for each pixel, thereby forming a modulated image on the screen of the display that forms the spatial light modulator 30. Will come to be. The modulated image (video light) thus obtained is projected onto the screen 15 at the same magnification or scaled by the projection optical system 25. As a result, the modulated image is displayed on the screen 15 at the same magnification or scaled (usually enlarged), and the observer can observe the image.

  As the spatial light modulator 30, a reflective micro display can be used. In this case, a modulated image is formed by the reflected light from the spatial light modulator 30, the surface on which the spatial light modulator 30 is irradiated with coherent light from the illumination device 40, and the image light that forms the modulated image from the spatial light modulator 30. The surface where the lead is the same surface. When such reflected light is used, a MEMS element such as a DMD (Digital Micromirror Device) can be used as the spatial light modulator 30. In the apparatus disclosed in Patent Document 2 described above, DMD is used as a spatial light modulator.

  Moreover, it is preferable that the incident surface of the spatial light modulator 30 has the same shape and size as the illuminated region LZ irradiated with the coherent light by the illumination device 40. In this case, it is because the coherent light from the illuminating device 40 can be used with high utilization efficiency for displaying the image on the screen 15.

  The screen 15 may be configured as a transmissive screen or may be configured as a reflective screen. In the case where the screen 15 is configured as a reflective screen, the observer observes an image displayed by coherent light reflected by the screen 15 from the same side as the projection device 20 with respect to the screen 15. On the other hand, when the screen 15 is configured as a transmissive screen, the observer observes an image displayed by coherent light transmitted through the screen 15 from the side opposite to the projection device 20 with respect to the screen 15. .

  By the way, the coherent light projected on the screen 15 is diffused and recognized as an image by the observer. At this time, the coherent light projected on the screen interferes by diffusion and causes speckle. However, in the projection display apparatus 10 described here, the illumination apparatus 40 described below illuminates the illuminated area LZ on which the spatial light modulator 30 is superimposed with coherent light that changes in angle with time. It is like that. More specifically, the illuminating device 40 described below illuminates the illuminated region LZ with diffused light composed of coherent light, and the incident angle of this diffused light changes over time. As a result, the diffusion pattern of the coherent light on the screen 15 also changes with time, and speckles generated by the diffusion of the coherent light are temporally superimposed and become inconspicuous. Hereinafter, such an illuminating device 40 will be described in more detail.

  The illumination device 40 shown in FIGS. 1 and 2 includes an optical element 50 that directs the traveling direction of the coherent light toward the illuminated region LZ, and an irradiation device 60 that irradiates the optical element 50 with the coherent light. . The optical element 50 includes a hologram recording medium that functions as a light diffusing element (light diffusing element), in particular, a hologram recording medium 55 that can reproduce the image 5 of the scattering plate 6. In the illustrated example, the optical element 50 is formed from a hologram recording medium 55.

  The hologram recording medium 55 constituting the optical element 50 in the illustrated example can receive the coherent light emitted from the irradiation device 60 as the reproduction illumination light La, and can diffract the coherent light with high efficiency. In particular, the hologram recording medium 55 can reproduce the image 5 of the scattering plate 6 by diffracting coherent light incident on each position, in other words, each minute region that should be called each point. ing.

  On the other hand, the irradiation device 60 irradiates the optical element 50 with the coherent light so that the coherent light of the hologram recording medium 55 scans the hologram recording medium 55 of the optical element 50. Therefore, the region on the hologram recording medium 55 that is irradiated with the coherent light by the irradiation device 60 at a certain moment is a part of the surface of the hologram recording medium 55, and in particular in the illustrated example, a minute region to be called a point. It has become.

  Then, the coherent light irradiated from the irradiation device 60 and scanned on the hologram recording medium 55 is diffracted by the hologram recording medium 55 at each position (each point or each region (hereinafter the same)) on the hologram recording medium 55. Incidence is made at an incident angle that satisfies the conditions. The coherent light incident on each position of the hologram recording medium 55 from the irradiation device 60 is diffracted by the hologram recording medium 55 and illuminates areas that overlap each other at least partially. In particular, in the embodiment described here, the coherent light incident on each position of the hologram recording medium 55 from the irradiation device 60 is diffracted by the hologram recording medium 55 to illuminate the same illuminated region LZ. . More specifically, as shown in FIG. 2, the coherent light incident on each position of the hologram recording medium 55 from the irradiation device 60 is superimposed on the illuminated region LZ to reproduce the image 5 of the scattering plate 6. It has become. That is, the coherent light that has entered the hologram recording medium 55 from the irradiation device 60 is diffused (expanded) by the optical element 50 and enters the illuminated area LZ.

  In the illustrated example, a reflection type volume hologram using a photopolymer is used as the hologram recording medium 55 that enables the diffraction action of such coherent light. As shown in FIG. 3, the hologram recording medium 55 is manufactured by using the scattered light from the actual scattering plate 6 as the object light Lo. FIG. 3 shows a state in which the hologram photosensitive material 58 having photosensitivity that forms the hologram recording medium 55 is exposed to the reference light Lr and the object light Lo, which are coherent light beams having coherence with each other. ,It is shown.

  As the reference light Lr, for example, laser light from a laser light source that oscillates laser light in a specific wavelength region is used, and passes through the condensing element 7 formed of a lens and enters the hologram photosensitive material 58. In the example shown in FIG. 3, the laser light that forms the reference light Lr is incident on the condensing element 7 as a parallel light beam parallel to the optical axis of the condensing element 7. The reference light Lr passes through the condensing element 7, so that it is shaped (converted) into a convergent light beam from the parallel light beam so far, and is incident on the hologram photosensitive material 58. At this time, the focal position FP of the convergent light beam Lr is at a position beyond the hologram photosensitive material 58. In other words, the hologram photosensitive material 58 is disposed between the condensing element 7 and the focal position FP of the convergent light beam Lr collected by the condensing element 7.

  Next, the object light Lo is incident on the hologram photosensitive material 58 as scattered light from a scattering plate 6 made of, for example, opal glass. Here, since the hologram recording medium 55 to be manufactured is a reflection type, the object light Lo is incident on the hologram photosensitive material 58 from the surface opposite to the reference light Lr. The object light Lo needs to have coherency with the reference light Lr. Therefore, for example, laser light oscillated from the same laser light source can be divided, and one of the divided lights can be used as the reference light Lr and the other can be used as the object light Lo.

  In the example shown in FIG. 3, a parallel light beam parallel to the normal direction to the plate surface of the scattering plate 6 is incident on and scattered by the scattering plate 6, and the scattered light transmitted through the scattering plate 6 is the object light Lo. The light enters the hologram photosensitive material 58. According to this method, when an isotropic scattering plate that is usually available at a low cost is used as the scattering plate 6, the object light Lo from the scattering plate 6 is incident on the hologram photosensitive material 58 with a substantially uniform light amount distribution. Is possible. Further, according to this method, although depending on the degree of scattering by the scattering plate 6, the reference light Lr is incident on each position of the hologram photosensitive material 58 with a substantially uniform light amount from the entire area of the exit surface 6 a of the scattering plate 6. It becomes easy. In such a case, the light incident on each position of the obtained hologram recording medium 55 reproduces the image 5 of the scattering plate 6 with the same brightness, and the reproduced scattering plate 6 It can be realized that the image 5 is observed with substantially uniform brightness.

  As described above, when the hologram recording material 58 is exposed to the reference light Lr and the object light Lo, an interference fringe formed by the interference of the reference light Lr and the object light Lo is generated. It is recorded on the hologram recording material 58 as a pattern (in the case of a volume hologram, for example, a refractive index modulation pattern). Thereafter, appropriate post-processing corresponding to the type of the hologram recording material 58 is performed, and the hologram recording medium 55 is obtained.

  FIG. 4 shows the diffraction action (reproduction action) of the hologram recording medium 55 obtained through the exposure process of FIG. As shown in FIG. 4, the hologram recording medium 55 formed from the hologram photosensitive material 58 of FIG. 3 is light having the same wavelength as the laser beam used in the exposure process, and the optical path of the reference light Lr in the exposure process. The light traveling in the opposite direction satisfies the Bragg condition. That is, as shown in FIG. 4, the reference point SP positioned with respect to the hologram recording medium 55 in the same positional relationship as the relative position of the focal point FP (see FIG. 3) with respect to the hologram photosensitive material 58 during the exposure process. The divergent light beam that diverges from the light and has the same wavelength as the reference light Lr during the exposure process is diffracted as the reproduction illumination light La to the hologram recording medium 55, and the relative position of the scattering plate 6 relative to the hologram photosensitive material 58 during the exposure process A reproduced image 5 of the scattering plate 6 is generated at a specific position with respect to the hologram recording medium 50 that has the same positional relationship as (see FIG. 3).

  At this time, the reproduction light (light obtained by diffracting the reproduction illumination light La by the hologram recording medium 55) Lb that generates the reproduction image 5 of the scattering plate 6 travels from the scattering plate 6 toward the hologram photosensitive material 58 during the exposure process. Each point of the image 5 of the scattering plate 6 is reproduced as light traveling in the opposite direction along the optical path of the object light Lo that has been emitted. As described above and as shown in FIG. 3, the scattered light Lo emitted from each position on the exit surface 6 a of the scattering plate 6 in the exposure process is incident on almost the entire region of the hologram photosensitive material 58. Is spreading (spreading). That is, the object light Lo from the entire area of the exit surface 6 a of the scattering plate 6 is incident on each position on the hologram photosensitive material 58, and as a result, information on the entire exit surface 6 a is placed on each position of the hologram recording medium 55. Each is recorded. For this reason, each light which forms the divergent light beam from the reference point SP functioning as the reproduction illumination light La shown in FIG. 4 is incident on each position of the hologram recording medium 55 independently and has the same contour. The image 5 of the scattering plate 6 can be reproduced at the same position (illuminated area LZ).

  On the other hand, the irradiation device 60 that irradiates the optical element 50 composed of the hologram recording medium 55 with the coherent light can be configured as follows. In the example shown in FIGS. 1 and 2, the irradiation device 60 includes a laser light source 61a that generates coherent light in a specific wavelength range, and a scanning device 65 that changes the traveling direction of the coherent light from the laser light source 61a. Have. The scanning device 65 changes the traveling direction of the coherent light with time, and directs it in various directions so that the traveling direction of the coherent light is not constant. As a result, the coherent light whose traveling direction is changed by the scanning device 65 scans the incident surface of the hologram recording medium 55 of the optical element 50.

  In particular, in the example shown in FIG. 2, the scanning device 65 includes a reflective device 66 having a reflective surface 66a that can be rotated about one axis RA1. More specifically, the reflection device 66 is configured as a mirror device having a mirror as a reflection surface 66a that can be rotated about one axis RA1. As shown in FIGS. 2 and 5, the mirror device 66 changes the traveling direction of coherent light from the laser light source 61a by changing the orientation of the mirror 66a. At this time, as shown in FIG. 2, the mirror device 66 generally receives coherent light from the laser light source 61a at the reference point SP. For this reason, the coherent light whose traveling direction is finally adjusted by the mirror device 66 is reproduced illumination light La (see FIG. 4) that can form one light beam diverging from the reference point SP, and the hologram recording medium 55 of the optical element 50. Can be incident. As a result, the coherent light from the irradiation device 60 scans on the hologram recording medium 55, and the image of the scattering plate 6 in which the coherent light incident on each position on the hologram recording medium 55 has the same contour. 5 is reproduced at the same position (illuminated area LZ).

  The mirror device 66 shown in FIG. 2 is configured to rotate the mirror 66a along one axis line RA1. FIG. 5 shows the configuration of the illumination device 40 shown in FIG. 2 as a perspective view. In the example shown in FIG. 5, the rotation axis RA <b> 1 of the mirror 66 a has an XY coordinate system defined on the plate surface of the hologram recording medium 55 (that is, the XY plane is parallel to the plate surface of the hologram recording medium 55. It extends parallel to the Y axis of the (XY coordinate system). Then, since the mirror 66a rotates around the axis line RA1 parallel to the Y axis of the XY coordinate system defined on the plate surface of the hologram recording medium 55, the coherent light from the irradiation device 60 is applied to the optical element 50. The incident point IP reciprocates in a direction parallel to the X axis of the XY coordinate system defined on the plate surface of the hologram recording medium 55. That is, in the example shown in FIG. 5, the irradiation device 60 irradiates the optical element 50 with coherent light so that the coherent light scans on the hologram recording medium 55 along a linear path.

  As a practical problem, the hologram recording material 58 may shrink when the hologram recording medium 55 is produced. In such a case, it is preferable to adjust the wavelength of the coherent light irradiated from the irradiation device 60 to the optical element 50 in consideration of the shrinkage of the hologram recording material 58. Therefore, the wavelength of the coherent light generated by the coherent light source 61a does not need to be exactly the same as the wavelength of the light used in the exposure process (recording process) in FIG. 3, and may be substantially the same.

  For the same reason, even if the traveling direction of the light incident on the hologram recording medium 55 of the optical element 50 does not take exactly the same path as the one light beam included in the divergent light beam from the reference point SP, it is illuminated. The image 5 can be reproduced in the region LZ. Actually, in the example shown in FIGS. 2 and 5, the mirror (reflecting surface) 66a of the mirror device 66 constituting the scanning device 65 is inevitably deviated from the rotation axis RA1. Therefore, when the mirror 66a is rotated around the rotation axis RA1 that does not pass through the reference point SP, the light incident on the hologram recording medium 55 may not be a single light beam that forms a divergent light beam from the reference point SP. is there. However, in practice, the image 5 can be substantially reproduced by being superimposed on the illuminated region LZ by coherent light from the irradiation device 60 having the illustrated configuration.

[Effects of basic form]
Next, the operation of the illumination device 40, the projection device 20, and the projection display device 10 having the above-described configuration will be described.

  First, the irradiation device 60 irradiates the optical element 50 with coherent light so that the coherent light scans the hologram recording medium 55 of the optical element 50. Specifically, coherent light having a specific wavelength traveling along a certain direction is generated by the laser light source 61 a, and the traveling direction of the coherent light is changed by the scanning device 65. The scanning device 65 causes coherent light having a specific wavelength to enter each position on the hologram recording medium 55 at an incident angle that satisfies the Bragg condition at the position. As a result, the coherent light incident at each position is superimposed on the illuminated region LZ by the diffraction at the hologram recording medium 55 to reproduce the image 5 of the scattering plate 6. That is, the coherent light that has entered the hologram recording medium 55 from the irradiation device 60 is diffused (expanded) by the optical element 50 and enters the entire illuminated area LZ. In this way, the irradiation device 60 illuminates the illuminated area LZ with coherent light.

  As shown in FIG. 1, in the projection device 20, the spatial light modulator 30 is arranged at a position overlapping the illuminated area LZ of the illumination device 40. For this reason, the spatial light modulator 30 is illuminated in a planar shape by the illumination device 40, and forms an image by selecting and transmitting the coherent light for each pixel. This image is projected onto the screen 15 by the projection optical system 25. The coherent light projected on the screen 15 is diffused and recognized as an image by the observer. However, at this time, the coherent light projected on the screen interferes by diffusion and causes speckle.

  However, according to the lighting device 40 in the basic mode described here, speckles can be made extremely inconspicuous as described below.

  According to the aforementioned Non-Patent Document 1, it is effective to multiplex parameters such as polarization, phase, angle, and time and increase the mode in order to make speckle inconspicuous. The mode here refers to speckle patterns that are uncorrelated with each other. For example, when coherent light is projected from different directions onto the same screen from a plurality of laser light sources, there are as many modes as the number of laser light sources. In addition, when coherent light from the same laser light source is projected onto the screen from different directions by dividing the time, the mode is the same as the number of times the incident direction of the coherent light has changed during the time that cannot be resolved by the human eye. Will exist. When there are a large number of these modes, the interference patterns of light are uncorrelated and averaged, and as a result, speckles observed by the observer's eyes are considered inconspicuous.

  In the irradiation device 60 described above, the optical element 50 is irradiated with the coherent light so as to scan the hologram recording medium 55. The coherent light incident on each position of the hologram recording medium 55 from the irradiation device 60 illuminates the entire illuminated area LZ with the coherent light, but the illumination of the coherent light that illuminates the illuminated area LZ. The directions are different from each other. Since the position on the hologram recording medium 55 where the coherent light enters changes with time, the incident direction of the coherent light to the illuminated region LZ also changes with time.

  Considering the illuminated area LZ as a reference, coherent light constantly enters each position in the illuminated area LZ, but the incident direction constantly changes as indicated by an arrow A1 in FIG. It will be. As a result, the light forming each pixel of the image formed by the light transmitted through the spatial light modulator 30 is projected to a specific position on the screen 15 while changing the optical path over time as indicated by an arrow A2 in FIG. Will come to be.

  The coherent light continuously scans on the hologram recording medium 55. Accordingly, the incident direction of the coherent light from the irradiation device 60 to the illuminated region LZ also changes continuously, and the incident direction of the coherent light from the projection device 20 to the screen 15 also changes continuously. Here, if the incident direction of the coherent light from the projection device 20 to the screen 15 changes only slightly (for example, several degrees), the speckle pattern generated on the screen 15 also changes greatly, and an uncorrelated speckle pattern. Are sufficiently superimposed. In addition, the frequency of scanning devices 65 such as MEMS mirrors and polygon mirrors that are commercially available is usually several hundred Hz or higher, and scanning devices 65 that reach tens of thousands of Hz are not uncommon.

  From the above, according to the basic form described above, the incident direction of the coherent light changes temporally at each position on the screen 15 displaying an image, and this change is caused by human eyes. As a result, a non-correlated coherent light scattering pattern is multiplexed and observed by the human eye. Therefore, speckles generated corresponding to each scattering pattern are overlapped and averaged and observed by an observer. Thereby, speckles can be made very inconspicuous for an observer who observes the image displayed on the screen 15.

  Note that conventional speckles observed by humans include not only speckles on the screen caused by scattering of coherent light on the screen 15, but also scattering of coherent light before being projected on the screen. Speckle on the projection device side can also occur. The speckle pattern generated on the projection device side is projected onto the screen 15 via the spatial light modulator 30 so that it can be recognized by the observer. However, according to the basic mode described above, the coherent light continuously scans on the hologram recording medium 55, and the coherent light incident on each position of the hologram recording medium 55 is superimposed on the spatial light modulator 30, respectively. The entire illuminated area LZ is illuminated. That is, the hologram recording medium 55 forms a new wavefront that is separate from the wavefront used to form the speckle pattern, and the illumination area LZ and further the spatial light modulator 30 are formed in a complex and uniform manner. Through this, the screen 15 is illuminated. Due to the formation of a new wavefront on the hologram recording medium 55, the speckle pattern generated on the projection apparatus side is made invisible.

  By the way, Non-Patent Document 1 described above proposes a method using a numerical value called speckle contrast (unit%) as a parameter indicating the degree of speckle generated on the screen. This speckle contrast is defined as a value obtained by dividing the standard deviation of the actual luminance variation on the screen divided by the average luminance value when displaying a test pattern image that should have a uniform luminance distribution. Amount. The larger the speckle contrast value is, the larger the speckle occurrence level on the screen is, which indicates that the spot-like luminance unevenness pattern is more prominently presented to the observer.

  The speckle contrast of the basic projection type image display apparatus 10 described with reference to FIGS. 1 to 5 was 3.0% (Condition 1). Further, as the above-described optical element 50, an uneven shape designed by using a computer so that the image 5 of the scattering plate 6 can be reproduced when receiving specific reproduction illumination light instead of the reflective volume hologram. The speckle contrast in the case of using the relief type hologram as a computer-generated hologram (CGH) having a ratio of 3.7% was (Condition 2). In HDTV (high-definition television) video display applications, a speckle contrast of 6.0% or less is a standard (for example, WO / 2001/081996) as a level at which an uneven brightness pattern is hardly recognized when an observer observes with the naked eye. The basic form described above sufficiently satisfies this standard. In addition, when actually observed with the naked eye, brightness unevenness (brightness unevenness) that could be visually recognized did not occur.

  On the other hand, when the laser light from the laser light source is shaped into a parallel light beam and incident on the spatial light modulator 30, that is, the spatial light modulator 30 of the projection display apparatus 10 shown in FIG. When the coherent light from the laser light source 61a was made incident as a parallel light beam without passing through 65 or the optical element 50, the speckle contrast was 20.7% (Condition 3). Under these conditions, a spot-like luminance unevenness pattern was observed quite noticeably by visual observation.

  Further, when the light source 61a is replaced with a green LED (non-coherent light source) and light from the LED light source is incident on the spatial light modulator 30, that is, the projection type video display device 10 shown in FIG. When the non-coherent light from the LED light source was incident as a parallel light beam on the spatial light modulator 30 without passing through the scanning device 65 and the optical element 50, the speckle contrast was 4.0% (Condition 4). Under these conditions, brightness unevenness (brightness unevenness) that could be visually recognized by naked eye observation did not occur.

  The results of Condition 1 and Condition 2 were much better than the results of Condition 3, and were also better than the measurement results of Condition 4. As already mentioned, the problem of speckle generation is a problem inherent in the case of using a coherent light source such as a laser beam in practice, and it is necessary to consider in an apparatus using a non-coherent light source such as an LED. There is no problem. In addition, in condition 1 and condition 2, as compared with condition 4, an optical element 50 that can cause speckles is added. From these points, it can be said that Condition 1 and Condition 2 were sufficient to cope with speckle defects.

  In addition, according to the basic mode described above, the following advantages can be obtained.

  According to the basic form described above, the optical element 50 for making speckles inconspicuous can also function as an optical member for shaping and adjusting the beam form of coherent light emitted from the irradiation device 60. Therefore, the optical system can be reduced in size and simplified.

  Further, according to the basic form described above, coherent light incident on each position of the hologram recording medium 55 generates an image 5 of the scattering plate 6 at the same position, and is superimposed on the image 5 to generate spatial light. A modulator 30 is arranged. Therefore, the light diffracted by the hologram recording medium 55 can be used for image formation with high efficiency, and the use efficiency of light from the light source 61a is excellent.

[Deformation to basic form]
Various modifications can be made to the basic form described based on the specific example illustrated in FIGS. Hereinafter, an example of modification will be described with reference to the drawings. In the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above-described embodiment are used, and redundant descriptions are omitted.

(Lighting device)
According to the embodiment described above, speckle can be effectively made inconspicuous. However, this effect is mainly due to the lighting device 40. Therefore, the lighting device 40 can be usefully used in various aspects. For example, the illumination device 40 can be used as simple illumination, and in this case, unevenness in brightness (luminance unevenness, flicker) can be made inconspicuous.

  Moreover, you may use the illuminating device 40 mentioned above as illumination for scanners (an image reading apparatus as an example). In such an example, the speckle generated on the target object can be made inconspicuous by arranging the target object to be scanned on the illuminated region LZ of the lighting device 40. As a result, it is possible to eliminate image correction means and the like that are conventionally required.

  When the illuminating device 40 is incorporated in a scanner, the illuminated area LZ by the illuminating device 40 may be a surface as in the above-described form. Alternatively, the illuminated region LZ by the illumination device 40 may be an elongated region (region also called a linear shape) extending in one direction. In this case, two-dimensional image information can be read by the illuminating device 40 incorporated in the scanner moving relative to the object along a direction orthogonal to the one direction.

  Furthermore, as shown in FIG. 6, the optical element 50 may include a plurality of hologram recording media 55-1, 55-2,... Arranged side by side so as not to overlap. Each of the hologram recording media 55-1, 55-2,... Shown in FIG. 6 is formed in a strip shape, and is arranged side by side with no gap in a direction orthogonal to the longitudinal direction. Further, the hologram recording media 55-1, 55-2,... Are located on the same virtual plane. Each hologram recording medium 55-1, 55-2,... Has an image 5 of the scattering plate 6 in the illuminated areas LZ-1, LZ-2,. Generate, in other words, illuminate the illuminated areas LZ-1, LZ-2,... With coherent light. Each of the illuminated areas LZ-1, LZ-2,... Is formed as an elongated area extending in one direction (an area that is also referred to as a linear shape), and is arranged side by side in a direction orthogonal to the longitudinal direction. ing. In addition, each of the illuminated areas LZ-1, LZ-2,... Is located on the same virtual plane.

  In the example shown in FIG. 6, the illuminated areas LZ-1, LZ-2,... May be illuminated as follows. First, the irradiation device 60 repeatedly scans the path along the longitudinal direction (the one direction) of the first hologram recording medium 55-1 so that the coherent light repeatedly scans the first hologram recording medium 55-of the optical element 50. 1 is irradiated with the coherent light. The coherent light incident on each position of the first hologram recording medium 55-1 is superimposed on the first illumination area LZ-1 to reproduce the image 5 of the linear or elongated scattering plate 6, and the first One illumination area LZ-1 is illuminated with coherent light. When a predetermined time elapses, the irradiation device 60 irradiates the second hologram recording medium 55-2 adjacent to the first hologram recording medium 55-1 with the coherent light, and the first illuminated region LZ-1 Instead, the second illuminated area LZ-2 adjacent to the first illuminated area LZ-1 is illuminated with coherent light. Hereinafter, the hologram recording medium is sequentially irradiated with coherent light, and the illuminated area corresponding to the hologram recording medium is illuminated with the coherent light. According to such a method, it is possible to read two-dimensional image information without moving the illumination device.

(Spatial light modulator, projection optical system, screen)
According to the embodiment described above, speckle can be effectively made inconspicuous. However, this effect is mainly due to the lighting device 40. Even if this lighting device 40 is combined with various known spatial light modulators, projection optical systems, screens, etc., speckles can be effectively made inconspicuous. From this point, the spatial light modulator, the projection optical system, and the screen are not limited to those illustrated, and various known members, components, devices, and the like can be used.

(Projection-type image display device)
Moreover, although the example in which the hologram recording medium 55 is manufactured by the interference exposure method using the planar scattering plate 6 having a shape corresponding to the incident surface of the spatial light modulator 30 is shown, the present invention is not limited thereto. The hologram recording medium 55 may be manufactured by an interference exposure method using a scattering plate having a certain pattern. In this case, the image of the scattering plate having a certain pattern is reproduced by the hologram recording medium 55. In other words, the optical element 50 (hologram recording medium 55) illuminates the illuminated area LZ having a certain pattern. When this optical element 50 is used, the spatial light modulator 30 and the projection optical system 25 are also omitted from the basic form described above, and the screen 15 is disposed on the screen 15 by overlapping with the illuminated region LZ. Any pattern recorded on the hologram recording medium 55 can be displayed. Also in this display device, the speckles on the screen 15 can be made inconspicuous by the irradiation device 60 irradiating the optical element 50 with the coherent light so that the coherent light scans the hologram recording medium 55. .

  FIG. 7 discloses an example of such an example. In the illustrated example, the optical element 50 includes first to third hologram recording media 55-1, 55-2, and 55-3. The first to third hologram recording media 55-1, 55-2, and 55-3 are arranged on surfaces parallel to the incident surface of the optical element 50 so as not to overlap each other. Each of the hologram recording media 55-1, 55-2, 55-3 can reproduce the image 5 having the outline of the arrow, in other words, the illuminated areas LZ-1, LZ- having the outline of the arrow. 2 and LZ-3 can be illuminated with coherent light. The first to third illuminated areas LZ-1, LZ-2, and LZ-3 respectively corresponding to the hologram recording media 55-1, 55-2, and 55-3 overlap each other on the same virtual plane. It is arranged not to become. In particular, in the illustrated example, the directions indicated by the arrows forming the illuminated areas LZ-1, LZ-2, and LZ-3 are all the same, and the first to third illuminated areas LZ-1, LZ-2 and LZ-3 are positioned in this order. For example, when the coherent light from the irradiation device 60 is scanning on the first hologram recording medium 55-1, the first illuminated region LZ-1 located at the rearmost side is illuminated. As an example, next, as shown in FIG. 7, the coherent light from the irradiation device 60 scans the second hologram recording medium 55-2, and the second illuminated region LZ-2 located in the middle is Illuminated. Thereafter, when the coherent light from the irradiation device 60 scans over the third hologram recording medium 55-3, the third illuminated area LZ-3 located in the foremost position is illuminated.

(Irradiation device)
In the embodiment described above, an example in which the irradiation device 60 includes the laser light source 61a and the scanning device 65 has been described. Although the scanning device 65 is an example of the uniaxial rotation type mirror device 66 that changes the traveling direction of the coherent light by reflection, the scanning device 65 is not limited thereto. As shown in FIG. 8, the scanning device 65 has a second rotation in which the mirror (reflection surface 66a) of the mirror device 66 intersects not only the first rotation axis RA1 but also the first rotation axis RA1. It may be rotatable about the axis RA2. In the example shown in FIG. 8, the second rotation axis RA2 of the mirror 66a is a first rotation axis RA1 extending in parallel with the Y axis of the XY coordinate system defined on the plate surface of the hologram recording medium 55. Are orthogonal. Since the mirror 66a is rotatable about both the first axis RA1 and the second axis RA2, the incident point IP of the coherent light from the irradiation device 60 to the optical element 50 is the plate of the hologram recording medium 55. It is possible to move in a two-dimensional direction on the surface. For this reason, as shown in FIG. 8 as an example, the incident point IP of the coherent light to the optical element 50 may be moved on the circumference.

  Further, the scanning device 65 may include two or more mirror devices 66. In this case, even if the mirror 66a of the mirror device 66 can be rotated only about a single axis, the incident point IP of the coherent light from the irradiation device 60 to the optical element 50 is expressed by the hologram recording medium 55. It can be moved in a two-dimensional direction on the plate surface.

  Specific examples of the mirror device 66a included in the scanning device 65 include a MEMS mirror and a polygon mirror.

  The scanning device 65 may include a device other than a reflection device (for example, the mirror device 66 described above) that changes the traveling direction of coherent light by reflection. For example, the scanning device 65 may include a refractive prism, a lens, and the like.

  In the first place, the scanning device 65 is not essential, and the light source 61a of the irradiation device 60 is configured to be displaceable (moving, swinging, rotating) with respect to the optical element 50, and from the light source 61a by the displacement of the light source 61a with respect to the optical element. The irradiated coherent light may be scanned on the hologram recording medium 55.

  Furthermore, although the light source 61a of the irradiation device 60 has been described on the assumption that the laser light shaped as a linear light beam is oscillated, the present invention is not limited to this. In particular, in the above-described form, the coherent light irradiated to each position of the optical element 50 is shaped by the optical element 50 into a light beam that enters the entire illuminated area LZ. Therefore, there is no inconvenience even if the coherent light irradiated to the optical element 50 from the light source 61a of the irradiation device 60 is not accurately shaped. For this reason, the coherent light generated from the light source 61a may be diverging light. Further, the cross-sectional shape of the coherent light generated from the light source 61a may be an ellipse or the like instead of a circle. Furthermore, the transverse mode of the coherent light generated from the light source 61a may be a multimode.

  When the light source 61a generates a divergent light beam, the coherent light is incident not on a point but in a region having a certain area when entering the hologram recording medium 55 of the optical element 50. In this case, the light diffracted by the hologram recording medium 55 and incident on each position of the illuminated area LZ is multiplexed in angle. In other words, at each moment, coherent light is incident on each position of the illuminated area LZ from a certain angle range. Speckle can be made more inconspicuous by such multiplexing of angles.

  Furthermore, although the irradiation apparatus 60 showed the example which injects coherent light into the optical element 50 so that the optical path of one light ray contained in a divergent light beam may be followed in the form mentioned above, it is not restricted to this. For example, in the embodiment described above, the scanning device 65 may further include a condensing lens 67 disposed on the downstream side of the mirror device 66 along the optical path of the coherent light. In this case, as shown in FIG. 9, the light from the mirror device 66 that travels along the optical path of the light beam constituting the divergent light beam becomes light that travels in a certain direction by the condenser lens 67. That is, the irradiation device 60 causes the coherent light to be incident on the optical element 50 so as to follow the optical path of the light beam constituting the parallel light flux. In such an example, a parallel light beam is used as the reference light Lr instead of the above-described convergent light beam in the exposure process when the hologram recording medium 55 is manufactured. Such a hologram recording medium 55 can be produced and duplicated more easily.

  In the above-described embodiment, an example in which the irradiation device 60 includes only a single laser light source 61a has been described. For example, the irradiation device 60 may include a plurality of light sources that oscillate light in the same wavelength region. In this case, the illumination device 40 can illuminate the illuminated area LZ more brightly. Further, coherent lights from different solid laser light sources do not have coherence with each other. Therefore, the multiplexing of the scattering pattern further proceeds and the speckle can be made less noticeable.

(Optical element)
In the embodiment described above, an example in which the optical element 50 includes the reflective volume hologram 55 using a photopolymer has been described, but the present invention is not limited thereto. As already described, the optical element 50 may include a plurality of hologram recording media 55. Further, the optical element 50 may include a volume hologram that is recorded using a photosensitive medium including a silver salt material. Further, the optical element 50 may include a transmission type volume hologram recording medium or a relief type (emboss type) hologram recording medium.

  However, in the relief (embossed) hologram, hologram interference fringes are recorded by the concavo-convex structure on the surface. However, in the case of this relief type hologram, scattering due to the uneven structure on the surface may become a new speckle generation factor. In this respect, the volume type hologram is preferable. In the volume hologram, since the hologram interference fringe is recorded as a refractive index modulation pattern (refractive index distribution) inside the medium, it is not affected by scattering due to the uneven structure on the surface.

  However, in the case of a volume hologram that is recorded using a photosensitive medium containing a silver salt material, scattering by silver salt particles may be a new speckle generation factor. In this respect, the hologram recording medium 55 is preferably a volume hologram using a photopolymer.

  In addition, in the exposure process shown in FIG. 3, a so-called Fresnel type hologram recording medium is produced. However, a Fourier transform type hologram recording medium obtained by performing recording using a lens may be produced. Absent. However, when a Fourier transform type hologram recording medium is used, a lens may also be used during image reproduction.

  Further, the striped pattern (refractive index modulation pattern or concave / convex pattern) to be formed on the hologram recording medium 55 does not use the actual object light Lo and reference light Lr, but the planned wavelength and incident direction of the reproduction illumination light La. In addition, it may be designed using a computer based on the shape and position of the image to be reproduced. The hologram recording medium 55 obtained in this way is also called a computer-generated hologram. When a plurality of coherent lights having different wavelength ranges are irradiated from the irradiation device 60 as in the above-described modification, the hologram recording medium 55 as a computer-generated hologram corresponds to each coherent light in each wavelength range. The coherent light in each wavelength region may be diffracted in the corresponding region to reproduce an image.

  Furthermore, in the embodiment described above, the optical element 50 expands the coherent light irradiated to each position, and uses the expanded coherent light as a light diffusing element that illuminates the entire illuminated area LZ. The hologram recording medium 55 Although the example which has is shown, it is not restricted to this. The optical element 50 changes or diffuses the traveling direction of the coherent light irradiated to each position instead of the hologram recording medium 55 or in addition to the hologram recording medium 55, and diffuses the entire illuminated area LZ with coherent light. You may make it have a lens array as a light-diffusion element (light-diffusion element) to illuminate. Specific examples of the lens array that functions as a light diffusing element include a total reflection type or a refractive type Fresnel lens or a fly-eye lens provided with a diffusion function. Also in such an illuminating device 40, the irradiating device 60 scans the lens array (light diffusing element) with the coherent light so as to irradiate the optical element 50 with the coherent light. The irradiation device 60 and the optical element 50 are configured so that the coherent light incident on each position of the optical element 50 is changed in the traveling direction by the lens array (light diffusing element) and illuminates the illuminated region LZ. Thus, speckle can be effectively inconspicuous.

(Lighting method)
In the embodiment described above, the irradiation device 60 is configured to be able to scan the coherent light on the optical element 50 in a one-dimensional direction, and the hologram recording medium 55 (light diffusion element) of the optical element 50 is irradiated to each position. An example is shown in which the coherent light is configured to diffuse (spread and diverge) in a two-dimensional direction, whereby the illumination device 40 illuminates the two-dimensional illuminated area LZ. However, as described above, the present invention is not limited to such an example. For example, the irradiation device 60 is configured to be able to scan the coherent light on the optical element 50 in a two-dimensional direction, and The hologram recording medium 55 of the optical element 50 ((light diffusing element) is configured to diffuse (spread and diverge) the coherent light irradiated to each position in a two-dimensional direction. 40 may illuminate a two-dimensional illuminated area LZ (aspect already described with reference to FIG. 8).

  Further, the irradiation device 60 is configured to be able to scan the coherent light on the optical element 50 in a one-dimensional direction, and the coherent light is irradiated to the hologram recording medium 55 (light diffusion element) of the optical element 50 at each position. The light may be configured to diffuse (spread and diverge) in a one-dimensional direction, and thereby the illumination device 40 may illuminate the one-dimensional illuminated area LZ. In this aspect, the scanning direction of the coherent light by the irradiation device 60 and the diffusion direction (expansion direction) of the hologram recording medium 55 (light diffusion element) of the optical element may be parallel to each other.

  Further, the irradiation device 60 is configured to be able to scan the coherent light in the one-dimensional direction or the two-dimensional direction on the optical element 50, and the hologram recording medium 55 (light diffusion element) of the optical element 50 is located at each position. The irradiated coherent light may be configured to diffuse (spread and diverge) in a one-dimensional direction. In this aspect, as already described, the optical element 50 has a plurality of hologram recording media 55 (light diffusing elements), and sequentially illuminates the illuminated areas LZ corresponding to the hologram recording media 55 (light diffusing elements). By doing so, the illumination device 40 may illuminate a two-dimensional area. At this time, each illuminated area LZ may be sequentially illuminated at a speed as if it were illuminated simultaneously by the human eye, or it can be recognized that the illuminated area LZ is also illuminated sequentially by the human eye. It may be illuminated sequentially at such a slow speed.

(Combination of modified examples)
In addition, although the some modification with respect to the basic form mentioned above has been demonstrated above, naturally, it is also possible to apply combining several modifications suitably.

<Application form>
[Configuration of application form and operation of application form]
Next, an application form obtained by applying the basic form described above will be described with reference to the illumination device 40, the projection device 20, and the projection video display device 10 illustrated in FIGS. In the following description, only points that are added to the above-described basic form will be described, and other parts that may be configured in the same manner as the above-described basic form are denoted by the same reference numerals as in the above-described basic form in FIGS. A duplicate description will be omitted. In the following, different aspects will be described, but the same reference numerals are used for portions that can be configured in common among the different aspects, and redundant description will be omitted.

  In the basic mode described above, the irradiation apparatus 60 has an example having only a single light source 61a that generates coherent light. The coherent light generated from the single light source 61a is typically light in a narrow wavelength band and is monochromatic light, as represented by laser light. Further, coherent light generated from a substantially usable light source, that is, a light source which can be obtained at a low cost and has a sufficient output is limited to light of a specific wavelength (range). That is, light of various colors cannot be displayed with light from a single light source. On the other hand, in many cases today, it is desirable to illuminate the illuminated area or display an image in a desired color that cannot be displayed with a single light source, or in multiple colors, typically full color. It is rare. An application mode (one embodiment of the present invention) described below is an application of the above-described basic mode in consideration of such points.

  In the applied form, the irradiation device 60 irradiates the optical element 50 with a plurality of coherent lights in different wavelength ranges. In the example shown in FIG. 10, the irradiation device 60 is configured to irradiate the optical element 50 with the combined light SL formed by combining a plurality of coherent lights in different wavelength ranges. In the example shown in FIG. 10, the irradiation device 60 includes the first coherent light La in the first wavelength range, the second coherent light Lb in the second wavelength range different from the first wavelength range, the first wavelength range, The synthetic light SL formed by synthesizing the third coherent light Lc in the third wavelength range different from both of the second wavelength ranges is irradiated. In particular, in the following, the first wavelength range corresponds to the first primary color component (blue component), and the second wavelength range corresponds to the second primary color component (green component) on the longer wavelength side than the first wavelength range. And, the third wavelength region corresponds to the third primary color component (red component) whose wavelength side is longer than the second wavelength region, and the irradiation device 60 uses additive color mixing of the first to third primary color components, An example in which white light can be irradiated will be described.

  In the example illustrated in FIG. 10, the irradiation apparatus 60 includes the above-described scanning device 65 and a light source mechanism 61 that generates the combined light SL. The light source mechanism 61 includes a plurality of light sources 61a, 61b, and 61c that respectively oscillate coherent light in a wavelength region corresponding to the wavelength region of each coherent light, and a combining device that combines the coherent light from the plurality of light sources 61a, 61b, and 61c. 62. The light source mechanism 61 includes, as a plurality of light sources, a first light source 61a that oscillates the first coherent light La in the first wavelength region, a second light source 61b that oscillates the second coherent light Lb in the second wavelength region, And a third light source 61c that oscillates the third coherent light Lc in the three wavelength regions. On the other hand, as the synthesizing device 62, various members, components, apparatuses, and the like that synthesize two lights can be used. In the illustrated example, a dichroic mirror having the advantage of being inexpensive and small compared with a cross dichroic prism or the like is used as the combining device 62.

  In the example shown in FIG. 10, the optical element 50 includes a hologram recording medium 55 made of a reflective volume hologram that diffracts the combined light and illuminates the illuminated region LZ. However, the reflective volume hologram has high wavelength selectivity. For this reason, the illustrated optical element 50 includes first to third hologram recording media 55-1, 55-2, and 55-3 provided corresponding to coherent light in each wavelength region. The first hologram recording medium 55-1 is provided corresponding to the first coherent light La in the first wavelength range, and the second hologram recording medium 55-2 corresponds to the second coherent light Lb in the second wavelength range. The third hologram recording medium 55-3 is provided corresponding to the third coherent light Lc in the third wavelength region.

  In addition, as shown in FIG. 11, the first to third hologram recording media 55-1, 55-2, 55-3 shown in FIG. Element 50 is formed. That is, the optical element 50 is planarly divided into a plurality of regions provided corresponding to the coherent light in each wavelength region, and the coherent light in each wavelength region is diffracted by the hologram recording medium forming the corresponding region. The image 5 of the scattering plate 6 is reproduced.

  In particular, in the example shown in FIG. 10, the first hologram recording medium 55-1 diffracts the first coherent light La in the first wavelength region as the reproduction illumination light, so that the second hologram recording medium 55-2 has the second wavelength. By diffracting the second coherent light Lb in the region as the reproduction illumination light, the third hologram recording medium 55-3 diffracts the third coherent light Lc in the third wavelength region as the reproduction illumination light. The image 5 of the scattering plate 6 can be reproduced. In addition, in the example shown in FIG. 10, the first hologram recording medium 55-1, the second hologram recording medium 55-2, and the third hologram recording medium 55-3 reproduce the corresponding coherent lights La, Lb, and Lc, respectively. The image 5 of the scattering plate 6 can be reproduced at positions overlapping with each other by being diffracted as illumination light.

  Note that the hologram recording media 55-1, 55-2, and 55-3 for coherent light in each wavelength range that constitute the combined light SL are used for exposure in the method already described with reference to FIGS. 3 and 4, for example. As the light (reference light Lr and object light Lo), coherent light in the corresponding wavelength region can be used.

  As shown in FIGS. 10 and 11, the first to third hologram recording media 55-1, 55-2, and 55-3 are arranged adjacent to each other on the same plane. Similarly to the basic form described above, when the irradiation device 60 irradiates the optical element 50 with the combined light SL, the hologram recording media 55-1, 55-2, 55- in which the combined light SL forms the optical element 50. 3 is scanned. When the synthesized light SL is irradiated on the first hologram recording medium 55-1, the first coherent light La in the synthesized light SL is diffracted by the first hologram recording medium 55-1, and the synthesized light SL is When the second hologram recording medium 55-2 is irradiated, the second coherent light Lb of the combined light SL is diffracted by the second hologram recording medium 55-2, and the combined light SL is the third hologram recording medium 55. −3, the third coherent light La of the combined light SL is diffracted by the third hologram recording medium 55-3, and the image 5 is reproduced so as to be superimposed on the illuminated area LZ, respectively. become.

  In other words, in this example, only the coherent light corresponding to any one wavelength region of the combined light SL that scans the hologram recording medium 55 of the optical element 50 is instantaneously irradiated with the illuminated region LZ (or The spatial light modulator 30) will be illuminated. The spatial light modulator 30 may include a color filter and may operate so as to always form a modulated image for each of the coherent lights La, Lb, and Lc in each wavelength range. Alternatively, the spatial light modulator 30 may be operated. May be operated in a time-sharing manner so as to form a modulated image corresponding to coherent light in the wavelength region irradiated on the light. As already described, the frequency of scanning devices 65 such as MEMS mirrors and polygon mirrors that are actually commercially available is usually several hundred Hz or higher, and scanning devices 65 that reach several tens of thousands of Hz are not uncommon. Thus, if the combined light SL is scanned at a very high speed, the human eye cannot recognize the color transition of the light that illuminates the illuminated region LZ (or the spatial light modulator 30). It is recognized that the illuminated area LZ (or the spatial light modulator 30) is illuminated by the combined light and an image is displayed by the combined light.

  As described above, in the application mode shown in FIG. 10, when the combined light SL from the irradiation device 60 is incident on the optical element 50, coherent light (first to third coherent light) in each wavelength region that forms the combined light. The image 5 of the scattering plate 6 is reproduced by each of La, Lb, and Lc so as to overlap the illuminated area LZ. As a result, the illuminated area LZ is illuminated with a color obtained by additive color mixing of the first to third coherent lights La, Lb, and Lc. That is, in this example, the illumination device 60 illuminates the illuminated area LZ with white light.

  In the projection device 20 or the transmissive image display device 10, the spatial light modulator 30 includes, for example, a color filter, and a modulated image can be formed for each of the coherent lights La, Lb, and Lc in each wavelength region. In this case, it is possible to display a video in a plurality of colors, and further to display a video in full color. Further, even if the spatial light modulation area does not include a color filter, the spatial light modulator 30 forms a modulated image corresponding to coherent light diffracted by the hologram recording medium irradiated with the synthesized light SL. Alternatively, it may be operated in a time division manner. Even in such an example, if the time-division operation is fast enough to be undetectable by the human eye, the image can be displayed in a plurality of colors when viewed by the human eye, and further, the image can be displayed in full color. Can be displayed.

  Further, according to the application mode shown in FIG. 10, similarly to the basic mode described above, the illuminated areas of the respective coherent lights La, Lb, and Lc diffracted by the hologram recording media 55a, 55b, and 55c of the optical element 50 are used. The incident direction to each position of LZ changes continuously. Accordingly, the incident direction of the image light composed of the first to third coherent lights La, Lb, and Lc projected from the projection device 20 to each position on the screen 15 also changes continuously. For this reason, as already described in the basic embodiment, uncorrelated speckle patterns are superimposed and averaged, and as a result, speckles observed by the observer's eyes can be made inconspicuous.

  In addition, in the form shown in FIG. 10, the first to third coherent lights La, Lb, and Lc simultaneously illuminate the illuminated region LZ and are projected onto the screen 15 at the same time. The first to third coherent lights La, Lb, and Lc are generated by different light sources 61a, 61b, and 61c, and thus have no coherency. That is, the speckle pattern resulting from each of the coherent lights La, Lb, and Lc is uncorrelated, and the uncorrelated speckle pattern is superimposed on the screen 15 and averaged. For this reason, in the application form shown in FIG. 10, the speckle pattern can be made less noticeable.

  By the way, it is known that the specific visual sensitivity of the human eye, that is, how the human eye perceives the brightness of the light changes according to the wavelength. For this reason, the speckle becomes easier to be visually recognized as the light having a wavelength range with higher specific visibility. FIG. 12 shows the photopic standard relative luminous sensitivity known as the standard specific luminous efficiency defined by CIE (Commission internationale de l'eclairage). As shown in FIG. 12, the relative visibility varies greatly depending on the wavelength, and the so-called three primary colors of light, the blue component light, the green component light, and the red component light are also compared. Sensitivity is very different. Therefore, in the illumination device 40, the projection device 20, and the projection type image display device 10 using a plurality of coherent lights in different wavelength regions, the speckle reduction effect is exerted more strongly with respect to coherent light with high specific vision sensitivity. By doing so, the speckle can be made inconspicuous very effectively as the whole apparatus.

  From this point of view, in an apparatus using a plurality of coherent lights in different wavelength regions, two incidents of coherent light that are incident on a certain point of the illuminated area (position where the image is reproduced) LZ from various directions. It is preferable that the maximum angle made by the direction (hereinafter referred to as “deflection angle”) is not the same among the plurality of coherent lights La, Lb, and Lc. Specifically, it is preferable that the magnitude of the deflection angle of each coherent light is adjusted in accordance with the relative visibility of the coherent light used in the apparatus.

  As described above, when coherent light is incident on each position of the illuminated region LZ from various directions, an uncorrelated scattering pattern is superimposed and averaged, and as a result, specs observed by the observer's eyes You can make it inconspicuous. Therefore, the larger the deflection angle when the coherent light is incident on the illuminated area (position where the image is reproduced) LZ, the more the non-correlated coherent light scattering patterns are multiplexed. As a result, as the deflection angle when the coherent light is incident on the illuminated region LZ is larger, speckles generated corresponding to each scattering pattern are overlapped and averaged. Can be made very effective and inconspicuous. Therefore, when the deflection angle of coherent light with higher relative visibility among multiple coherent lights in different wavelength ranges is large, it exerts a stronger speckle reduction effect on the coherent light that is likely to cause speckle. As a result, speckles in the entire apparatus can be effectively made inconspicuous.

  10 and FIG. 11, the deflection angle θb of the second coherent light Lb, which is the green component light with the highest relative visibility, is larger than the deflection angles θa, θc of the other coherent lights La, Lc. As a result, speckles can be made inconspicuous very effectively.

  The “one point” in the illuminated area (position where the image is reproduced) LZ for specifying the deflection angle is preferably the center of the illuminated area LZ, and each position in the illuminated area LZ. That is, it is more preferable that it is an arbitrary position in the illuminated area LZ. Here, the center of the illuminated area LZ is the position of the center of gravity based on the outer contour of the illuminated area, and is the position where the observer is most sensitive to the display image quality.

  10 and FIG. 11, the deflection angle θb of the second coherent light Lb, which is the green component light with the highest specific visibility, is larger than the deflection angles θa and θc of the other coherent lights, Thereby, speckles can be made inconspicuous very effectively. In the embodiment shown in FIGS. 10 and 11, the deflection angles θa, θb, and θc are adjusted specifically as described below.

  10 and 11, the scanning device 65 of the irradiation apparatus 60 includes a reflection device 66 having a reflection surface 66a that can be rotated about only one axis RA1. Therefore, as shown in FIG. 11, the coherent light irradiated to the optical element 50 from the irradiation device 60 is on the plurality of hologram recording media 55-1, 55-2, and 55-3 along the linear scanning path. Scan repeatedly. As shown in FIG. 11, the length Xb of the scanning path on the second hologram recording medium 55-2 corresponding to the second coherent light Lb is the scanning on the hologram recording medium 55-1 of the first coherent light La. It is longer than the path length Xa and longer than the scanning path length Xc of the third coherent light Lc on the hologram recording medium 55-3. As a result, as shown in FIG. 10, the shake angle θb of the second coherent light Lb is larger than the shake angle θa of the first coherent light La and larger than the shake angle θc of the third coherent light Lc. Yes.

  In the example shown in FIGS. 10 and 11, the length Xc of the scanning path of the synthesized light SL on the hologram recording medium 55-3 of the third coherent light Lc is set to the first coherent according to the magnitude of the specific visibility. The length La of the scanning path of the combined light SL on the hologram recording medium 55-1 of the light La is made longer, and thereby the deflection angle θc of the third coherent light Lc corresponding to the light of the red component is changed to that of the blue component. The deflection angle θa of the first coherent light La corresponding to the light is made larger. However, in the example shown in FIGS. 10 and 11 and also in the examples described later, the speckle reduction effect on the first coherent light La corresponding to the blue component light and the first corresponding to the red component light are the same. The speckle reduction effect on the 3 coherent light Lc does not have to be superior or inferior.

  Incidentally, in the examples shown in FIGS. 10 and 11, the widths of the hologram recording media along the direction parallel to the scanning path of the combined light SL are not the same. Specifically, the width of the hologram recording medium 55-2 corresponding to the second coherent light Lb along the direction parallel to the scanning path of the combined light SL is the first width along the direction parallel to the scanning path of the combined light SL. It is longer than the width of the hologram recording medium 55-1 of the 1 coherent light La and longer than the width of the hologram recording medium 55-3 of the third coherent light Lc along the direction parallel to the scanning path of the combined light SL. . By adjusting the widths of the hologram recording media 55-1, 55-2, and 55-3, the scanning paths on the hologram recording media 55-1, 55-2, and 55-3 are made different.

  10 and 11, the irradiation device 60 synthesizes the coherent light from each of the light sources 61a, 61b, 61c and irradiates the optical element 50 as synthesized light, that is, each light source 61a. , 61b, 61c show an example in which the time when the coherent light is generated is the same. However, the present invention is not limited to this example, and the generation time of each of the light sources 61a, 61b, and 61c of the coherent light La, Lb, and Lc irradiated on the optical element 50 along the same optical path by the combining device 62 is adjusted. Also good. That is, the time when each of the light sources 61a, 61b, 61c is generating coherent light may not be the same.

  As an example, when the scanning device 65 directs the traveling direction of the coherent light toward the first hologram recording medium 55-1, only the first light source 61a generates the coherent light, and the scanning device 65 changes the traveling direction of the coherent light to the first hologram recording medium 55-1. When directed to the second hologram recording medium 55-2, only the second light source 61b generates coherent light, and when the scanning device 65 directs the traveling direction of the coherent light toward the third hologram recording medium 55-3, Only the three light sources 61c may generate coherent light. At this time, the lengths of the scanning paths Xa, Xb on the hologram recording media 55-1, 55-2, 55-3 are adjusted by adjusting the time during which the light sources 61a, 61b, 61c generate the coherent light. , Xc can be controlled, and as a result, the deflection angles θa, θb, θc of the coherent lights La, Lb, Lc are controlled regardless of the widths of the hologram recording media 55-1, 55-2, 55-3. can do.

  In the first place, the coherent light La, Lb, and Lc generated by each of the light sources 61a, 61b, and 61c may be irradiated to the optical element 50 along different paths. In addition, the coherent lights La, Lb, and Lc generated by the light sources 61a, 61b, and 61c are scanned on the hologram recording medium, particularly the corresponding hologram recording medium, by the scanning device assigned to each of the light sources 61a, 61b, and 61c. Also good. That is, the irradiation device 60 is provided corresponding to each of the coherent lights La, Lb, and Lc from the light sources 61a, 61b, and 61c, and the coherent lights La, Lb, and Lc from the corresponding light sources 61a, 61b, and 61c travel. A plurality of scanning devices that change the direction so that the coherent lights La, Lb, and Lc scan the hologram recording medium 55-1, 55-2, and 55-3 may be included. According to these examples, the degree of freedom in adjusting the deflection angles θa, θb, and θc can be increased.

  Next, another aspect using a plurality of coherent lights in different wavelength ranges will be described with reference to FIG. In the embodiment shown in FIG. 13 described below, the speckle can be effectively made inconspicuous by adjusting the magnitudes of the deflection angles θa, θb, θc of the coherent lights La, Lb, Lc. It has become. In FIG. 13 and FIG. 14 described next, the projection optical system 25 and the screen 15 are omitted.

  In the embodiment shown in FIG. 13, a plurality of hologram recording media 55-1, 55-2, and 55-3 for diffracting each of the coherent lights La, Lb, and Lc are arranged in an overlapping manner to form the optical element 50. In the point which is carrying out, it differs from the aspect shown in FIG. 10 and FIG. However, also in the aspect shown in FIG. 13, the first coherent light La is diffracted by the first hologram recording medium 55-1 and the second coherent light Lb is diffracted by the second hologram recording medium 55-2. The third coherent light La is diffracted by the third hologram recording medium 55-3, and the same image 5 is reproduced while being superimposed on the same illuminated area LZ.

  In the mode shown in FIG. 13, for example, by adjusting the generation time of the coherent light La, Lb, and Lc in the light sources 61a, 61b, and 61c, the deflection angles θa, The magnitudes of θb and θc can be adjusted. For example, as in the example shown in FIGS. 10 and 11, the coherent lights La, Lb, and Lc are scanned along the linear scanning path on the hologram recording media 55-1, 55-2, and 55-3. And adjusting the generation time of the coherent lights La, Lb, and Lc in the light sources 61a, 61b, and 61c to obtain the scanning path lengths Xa, Xb, and Xc of the coherent lights La, Lb, and Lc, respectively. By adjusting, the magnitudes of the deflection angles θa, θb, and θc of the coherent lights La, Lb, and Lc can be controlled.

  In the example shown in FIG. 13, the length Xb of the scanning path on the second hologram recording medium 55-2 corresponding to the second coherent light Lb is equal to the scanning path on the hologram recording medium 55-1 of the first coherent light La. It is longer than the length Xa and longer than the length Xc of the scanning path of the third coherent light Lc on the hologram recording medium 55-3. As a result, the shake angle θb of the second coherent light Lb is larger than the shake angle θa of the first coherent light La and larger than the shake angle θc of the third coherent light Lc. In the embodiment shown in FIG. 13, the length Xc of the scanning path on the third hologram recording medium 55-3 corresponding to the third coherent light Lc is the same as that on the hologram recording medium 55-1 of the first coherent light La. Is longer than the scanning path length Xa. As a result, the shake angle θc of the third coherent light Lc is larger than the shake angle θa of the first coherent light La.

  In the example shown in FIG. 13, instead of manufacturing the optical element 50 by laminating the first to third hologram recording media 55-1, 55-2, and 55-3, each of the wavelength regions includes coherent light. The object light Lo and the reference light Lr are exposed to the single hologram photosensitive material 58 at the same time or at different timings so that light in a plurality of wavelength ranges is diffracted by the single hologram recording medium 55, respectively. May be. As represented by laser light, coherent light having different wavelength ranges is generated from different light sources and is not coherent with each other. Therefore, even if the hologram photosensitive material 58 is simultaneously exposed to coherent light in different wavelength regions, interference fringes between coherent light in different wavelength regions are not generated. That is, unnecessary interference fringes are not recorded on the hologram photosensitive material 58, and the hologram recording medium 55 made of the hologram photosensitive material 58 diffracts a plurality of coherent lights in different wavelength ranges with high efficiency. can do.

  Next, another mode using a plurality of coherent lights in different wavelength ranges will be described with reference to FIG. Also in the embodiment shown in FIG. 14 described below, the speckle can be effectively made inconspicuous by adjusting the magnitudes of the deflection angles θa, θb, and θc for the coherent lights La, Lb, and Lc. It is like that.

  The irradiation device 60 shown in FIG. 14 includes a plurality of light sources 61a, 61b, and 61c that respectively generate a plurality of coherent lights La, Lb, and Lc having different wavelength ranges, and a coherent light from the plurality of light sources 61a, 61b, and 61c. A single scanning device 65 that changes the traveling directions of La, Lb, and Lc so that the coherent lights La, Lb, and Lc scan on the hologram recording media 55-1, 55-2, and 55-3; , Including. A plurality of coherent lights La, Lb, and Lc having different wavelength ranges are incident on the scanning device 65 from different directions, and the traveling directions can be changed in different directions.

  In particular, in the example shown in FIG. 14, the scanning device 65 includes a reflecting device 66 having a reflecting surface 66 a that can be rotated about one axis RA <b> 1. Coherent light La, Lb, Lc is received from different directions. In the example shown in FIG. 14, the irradiation device 60 includes a lens 64 disposed in the optical path from each light source 61 a, 61 b, 61 c to the scanning device 65, and each light source 61 a, 61 b is provided by this lens 64. , 61c are directed to a reference point SP on the reflection surface 66a of the reflection device 66. The plurality of coherent lights La, Lb, Lc proceeding in parallel with each other.

  On the other hand, in the example shown in FIG. 14, first to third optical elements each including first to third hologram recording media 55-1, 55-2 and 55-3 respectively corresponding to coherent light in each wavelength range. 50-1, 50-2, and 50-3 are provided. In the example shown in FIG. 14, the first hologram recording medium 55-1 of the first optical element 50-1 diffracts the first coherent light La in the first wavelength region as the reproduction illumination light, so that the second The second hologram recording medium 55-2 of the optical element 50-2 diffracts the second coherent light Lb in the second wavelength region as reproduction illumination light, and further, the third hologram recording medium of the third optical element 50-3. 55-3 diffracts the third coherent light Lc in the third wavelength region as reproduction illumination light, so that the images 5 of the same scattering plate 6 are reproduced at positions overlapping with the same illuminated region LZ. It has become.

  In the example shown in FIG. 14, by adjusting the distances between the hologram recording media 55-1, 55-2, and 55-3 and the illuminated region LZ, the deflection angles θa of the coherent lights La, Lb, and Lc, The magnitudes of θb and θc can be adjusted. Specifically, the deflection angle of the coherent light diffracted by the hologram recording medium arranged at a position close to the illuminated region LZ can be increased. In the example shown in FIG. 14, the hologram recording medium 55-2 corresponding to the second coherent light Lb is a hologram recording medium 55-1 corresponding to the first coherent light La and the hologram recording corresponding to the third coherent light Lc. It is arranged closer to the illuminated area (position where the image is reproduced) LZ than the medium 55-3. The hologram recording medium 55-3 corresponding to the third coherent light Lc is arranged closer to the illuminated area (position where the image is reproduced) LZ than the hologram recording medium 55-1 corresponding to the first coherent light La. Has been. As a result, the shake angle θb of the second coherent light Lb is larger than the shake angle θa of the first coherent La and the shake angle θc of the third coherent Lc, and the shake angle θc of the third coherent light Lc is It is larger than the deflection angle θa of one coherent La.

  In the explanation of the above-described applied mode, in the apparatus using a plurality of coherent lights in different wavelength ranges, it is explained that the deflection angle of the coherent light is increased as a technique for enhancing the speckle reduction effect for the specific coherent light. I have done it. However, as a technique for enhancing the speckle reduction effect for specific coherent light, instead of increasing the deflection angle of the coherent light or in addition to increasing the deflection angle of the coherent light, Increasing the scanning speed on the element 50 is also effective.

  As described above, when coherent light is incident on each position of the illuminated region LZ from various directions, an uncorrelated scattering pattern is superimposed and averaged, and as a result, specs observed by the observer's eyes You can make it inconspicuous. Therefore, as the scanning speed of the coherent light on the optical element 50 increases, the non-correlated coherent light scattering pattern is multiplexed in a certain time. As a result, as the scanning speed of the coherent light on the optical element 50 increases, speckles generated corresponding to each scattering pattern are overlapped and averaged, and speckles due to the coherent light are extremely reduced. It can be effectively inconspicuous. Therefore, when the scanning speed of the coherent light having a higher relative visibility among the plurality of coherent lights in different wavelength ranges on the optical element 50 is increased, the specs stronger than the coherent light that is likely to cause speckle. As a result, speckles in the entire apparatus can be effectively made inconspicuous.

  Therefore, in the aspect using a plurality of coherent lights in different wavelength ranges that have been described as the application form, the second coherent light Lb that is the green component light having the highest relative visibility on the second hologram recording medium 55-2. By making the scanning speed at the higher than the scanning speed of the other coherent lights Lb and Lc on the corresponding hologram recording media 55-1 and 55-3, the speckles can be made extremely inconspicuous. Can do. In particular, when the shake angles θa, θb, θc of the plurality of coherent lights La, Lb, Lc are the same as each other, and furthermore, the hologram recording media 55-1, 55-2 of the plurality of coherent lights La, Lb, Lc. , 55-3, the scanning speed on the optical element of the coherent light is adjusted in accordance with the relative visibility of the coherent light, so that the speckle is effectively inconspicuous. It is effective in letting

  Further, as a technique for enhancing the speckle reduction effect for specific coherent light, each of the coherent lights La, Lb, and Lc periodically and repeatedly scans a certain scanning path on the optical element 50 (hologram recording medium 55). In this case, it is also effective to increase the length of the predetermined scanning path (the total length of the scanning path) on the optical element 50 (hologram recording medium 55) scanned by the specific coherent light. This technique can be employed instead of increasing the deflection angle of the coherent light or in addition to increasing the deflection angle of the coherent light.

  As described above, when coherent light is incident on each position of the illuminated region LZ from various directions, an uncorrelated scattering pattern is superimposed and averaged, and as a result, specs observed by the observer's eyes You can make it inconspicuous. Therefore, as the length of the constant scanning path of coherent light is longer, the non-correlated light scattering pattern is more multiplexed while the coherent light scans the constant scanning path. As a result, as the length of the constant scanning path of coherent light is longer, speckles generated corresponding to each scattering pattern are overlapped and averaged, and speckles due to the coherent light are extremely reduced. It can be effectively inconspicuous. Therefore, when the length of a certain scanning path on the optical element 50 of coherent light having a higher relative visibility among a plurality of coherent lights in different wavelength ranges is long, speckle is likely to occur. On the other hand, it is possible to exert a stronger speckle reduction action, and as a result, speckles in the entire apparatus can be effectively made inconspicuous.

  Therefore, in the aspect using a plurality of coherent lights in different wavelength ranges described as application forms, each of the plurality of coherent lights periodically scans a certain scanning path on the optical element 50 (hologram recording medium 55). In this case, the length of the scanning path on the second hologram recording medium 55-2 (the total length of the scanning path) of the second coherent light Lb, which is the green component light having the highest specific visibility, is the other coherent light Lb, By making the length longer than the length of the scanning path on the hologram recording media 55-1 and 55-3 corresponding to Lc (the total length of the scanning path), the speckles can be made extremely inconspicuous. In particular, when the shake angles θa, θb, and θc of the plurality of coherent lights La, Lb, and Lc are the same as each other, and further, the plurality of coherent lights La, Lb, and Lc are the hologram recording media 55-1, 55-2. , 55-3, the time (cycle) required to travel the entire length of the scanning path is the same as each other, the constant scanning path on the optical element of the coherent light according to the relative visibility of the coherent light. Adjusting the length (the total length of the scanning path) is effective in effectively making the speckle inconspicuous.

  As a specific example, the irradiation device 60 includes a plurality of light sources 61a, 61b, and 61c that respectively generate a plurality of coherent lights La, Lb, and Lc having different wavelength ranges, and a coherent light La from each of the light sources 61a, 61b, and 61c. Lb and Lc are provided in correspondence with each other, and the traveling directions of the coherent lights La, Lb, and Lc from the corresponding light sources 61a, 61b, and 61c are changed, and the coherent lights La, Lb, and Lc are scanned on the hologram recording medium. A mode including a plurality of scanning devices 65-1, 65-2, and 65-3 to be performed is examined (for example, a mode of FIG. 16 described later). Then, as shown in FIG. 15, the coherent light La, Lb, Lc is on the hologram recording medium 55 at a constant first direction frequency (or first direction frequency) along the first direction (Y-axis direction). It vibrates and vibrates at a constant second direction frequency (or second direction frequency) equal to or lower than the first direction frequency even in the second direction (X-axis direction) intersecting (for example, orthogonal to) the first direction. Thus, it is assumed that each of the plurality of scanning devices 65-1, 65-2, 65-3 changes the traveling direction of the coherent light corresponding thereto.

  Note that the scanning devices 65-1, 65-2, and 65-3 shown in FIG. 15 are configured in the same manner as the scanning device 65 described with reference to FIG.

  As shown in FIG. 15, when the scanning devices 65-1, 65-2, and 65-3 change the traveling direction of the coherent light La, Lb, and Lc, the traveling direction of the coherent light with high relative visibility is changed. It is preferable to set a large value of the ratio of the first direction frequency to the second direction frequency of the scanning device to be changed. When the ratio value increases, the length Zy that the coherent light scans along the first direction and the length Zyx that scans along the second direction are kept constant, that is, the deflection angle θz is kept substantially constant. However, the length of the scanning path per cycle of the coherent light on the hologram recording medium 55 (the length of the constant scanning path) can be increased, thereby making speckles inconspicuous. it can.

  Therefore, in the aspect using a plurality of coherent lights in different wavelength ranges described as application forms, each of the plurality of coherent lights periodically scans a certain scanning path on the optical element 50 (hologram recording medium 55). In this case, the ratio of the first direction frequency to the second direction frequency equal to or lower than the first direction frequency of the scanning device that changes the traveling direction of the second coherent light Lb changes the traveling direction of the first coherent light La. The first direction vibration of the scanning device that changes the value of the ratio of the first direction frequency to the second direction frequency less than or equal to the first direction frequency of the scanning device and the traveling direction of the coherent light of the third coherent light Lc. It is preferable to make the speckle inconspicuous when it is larger than the value of the ratio of the first direction frequency to the second direction frequency less than the number. The ratio of the first direction frequency to the second direction frequency equal to or lower than the first direction frequency of the scanning device that changes the traveling direction of the third coherent light Lc is the progression of the coherent light of the first coherent light La. A ratio larger than the ratio of the first direction frequency to the second direction frequency less than or equal to the first direction frequency of the scanning device that changes the direction is preferable in order to make the speckle inconspicuous. In particular, when the scanning time per cycle of the coherent light on the hologram recording medium 55 is the same among the plurality of coherent lights, that is, when the second direction frequency of the plurality of scanning devices is the same, Speckle can be made inconspicuous effectively.

  Furthermore, in the application form described above, an example in which a plurality of coherent lights La, Lb, and Lc in different wavelength regions reproduce the image 5 of the scattering plate 6 at the same position is shown, but the present invention is not limited to this. As an example, as shown in FIGS. 16 and 17, a plurality of coherent lights La, Lb, and Lc in different wavelength regions may reproduce the image 5 of the scattering plate 6 at different positions. In such an aspect, the coherent light is adjusted by adjusting the swing angle of each coherent light according to the specific visibility of the coherent light used and / or according to the specific visibility of the coherent light used. By adjusting the scanning speed of light on the optical element 50 and / or when each of the plurality of coherent lights periodically scans a certain scanning path on the optical element 50 (hologram recording medium 55). The speckle is effectively made inconspicuous by adjusting the length of the constant scanning path (the total length of the scanning path) of the coherent light on the optical element 50 according to the specific visibility of the coherent light used. I can.

  In the aspect shown in FIG. 16, a plurality of light sources 61a, 61b, and 61c that generate a plurality of coherent lights La, Lb, and Lc in different wavelength ranges are provided. Scanning devices 65-1, 65-2, and 65-3 and optical elements 50-1, 50-2, and 50-3 are provided for the light sources 61a, 61b, and 61c, respectively. In addition, spatial light modulators 30-1, 30-2, and 30-3 are provided at positions that overlap with the image 6 reproduced by the coherent lights La, Lb, and Lc, that is, positions that overlap the illuminated areas, respectively. It has been. Further, a combined projection optical system 26 that combines and projects the modulated images obtained on the spatial light modulators 30-1, 30-2, and 30-3 is provided. The composite projection optical system 26 includes a device that synthesizes the modulated image, for example, a dichroic prism 26a, and a device that projects the combined modulated image on the screen 15, for example, a lens 26b.

  In the aspect shown in FIG. 16, each modulated image projected on the screen 15 can make speckles inconspicuous as described in the basic mode. Furthermore, by adjusting the generation time of coherent light in each of the light sources 61a, 61b, and 61c, and controlling the operations of the scanning devices 65-1, 65-2, and 65-3, the shake described in the application mode is performed. By controlling one or more of the size of the corner, the scanning speed on the optical element 50, and the length of the scanning path for one cycle on the optical element 50, the relative visibility of the coherent light is taken into consideration. Speckle can be made inconspicuous extremely effectively.

  The embodiment shown in FIG. 17 is different from the embodiment shown in FIG. 16 in that only a single scanning device is provided. That is, in the aspect shown in FIG. 17, the irradiation device 60 has a plurality of light sources 61a that respectively generate a plurality of coherent lights La, Lb, and Lc having different wavelength ranges, as in the aspect described with reference to FIG. , 61b, 61c and the traveling directions of the coherent light La, Lb, Lc from the plurality of light sources 61a, 61b, 61c are changed so that the coherent light La, Lb, Lc is generated by the hologram recording media 55-1, 55-2. , 55-3, and a single scanning device 65 adapted to scan. A plurality of coherent lights La, Lb, and Lc having different wavelength ranges are incident on the single scanning device 65 from different directions, and their traveling directions can be changed in different directions.

  In particular, in the example shown in FIG. 17, the scanning device 65 includes a reflecting device 66 having a reflecting surface 66 a that can be rotated about one axis RA <b> 1. Coherent light La, Lb, Lc is received from different directions. In the example shown in FIG. 17, the irradiation device 60 includes a lens 64 disposed in the optical path from each light source 61 a, 61 b, 61 c to the scanning device 65, and each light source 61 a, 61 b is provided by this lens 64. , 61c are directed to a reference point SP on the reflection surface 66a of the reflection device 66. The plurality of coherent lights La, Lb, Lc proceeding in parallel with each other. The coherent lights La, Lb, and Lc traveling in different directions from the scanning device 65 are guided to the optical elements 50-1, 50-2, and 50-3 by the guiding device 27 including a mirror or the like. The configurations after the optical elements 50-1, 50-2, and 50-3 can be configured in the same manner as the mode shown in FIG.

  In such an embodiment shown in FIG. 17, by increasing the optical path length from the only scanning device 65 to each optical element 50-1, 50-2, 50-3, each coherent light is irradiated in the illuminated region LZ. The deflection angles θa, θb, and θc when entering each position of the (spatial light modulator) can be increased. That is, the deflection angles θa, θb, and θc of the plurality of coherent lights La, Lb, and Lc can be adjusted according to the relative visibility of the coherent light, thereby making speckles inconspicuous extremely effectively. Can do.

  The following various modifications can be made to the application mode described with reference to a plurality of specific examples illustrated in FIGS. Hereinafter, an example of the change (deformation) will be described.

  First, the modified examples described with respect to the basic form can naturally be adopted in the applied form.

  For example, the example in which each of the hologram recording media 55a, 55b, and 55c is configured as a reflective volume hologram has been described, but the present invention is not limited thereto. Each hologram recording medium 55a, 55b, 55c may be configured as a transmission type volume hologram. Note that the transmission type volume hologram has lower wavelength selectivity than the reflection type volume hologram. However, the wavelength selectivity of the transmission-type volume hologram can be adjusted by a measure such as increasing the film thickness of the hologram photosensitive material 58, for example. Then, by adjusting the wavelength selectivity of the transmission type volume hologram, each transmission type volume hologram diffracts only the coherent light in the target wavelength region with high efficiency, and the wavelength that is not the target. It can be avoided that the path of the coherent light in the region is greatly bent.

  Further, the striped pattern (refractive index modulation pattern or concavo-convex pattern) to be formed on the hologram recording medium 55 can be obtained without using the actual object light Lo and the reference light Lr. In addition, a hologram (so-called computer-generated hologram) designed using a computer based on the shape, position, etc. of the image to be reproduced can also be used as the hologram recording medium 55. A hologram recording medium 55 as a computer-generated hologram is planarly divided into a plurality of regions provided corresponding to the coherent light in each wavelength region, and the coherent light in each wavelength region is diffracted in the corresponding region and imaged. May be played back.

  Further, as described as a modification to the basic form, the optical element 50 changes the traveling direction of the coherent light irradiated to each position and diffuses it so as to illuminate the entire area to be illuminated LZ with the coherent light. As a diffusing element (light diffusing element), a lens array may be provided instead of or in addition to the hologram recording medium 55. Also in such an aspect, the magnitude of the deflection angle, the scanning speed on the optical element 50, and the length of the scanning path for one cycle on the optical element 50 are determined according to the relative visibility of the coherent light used. By adjusting one or more of the lengths, speckles can be effectively made inconspicuous as a whole apparatus.

  In the case where the optical element 50 has a lens array as a light diffusing element (light diffusing element), a plurality of coherent lights La, Lb, and Lc in different wavelength regions may be subjected to different optical effects from different lens arrays. The traveling direction can be changed so as to illuminate the illuminated area LZ with a single lens array. However, since one or more of the deflection angle, the scanning speed on the optical element 50, and the length of the scanning path for one cycle on the optical element 50 are controlled for each coherent light, the wavelength ranges are different. A plurality of lens arrays may be provided corresponding to each coherent light. Similarly to the case of using the hologram recording medium described above, by adjusting the optical path of the coherent light and the generation time in the light sources 61a, 61b, 61c, according to the relative visibility of the coherent light used, It is also possible to control one or more of the magnitude of the deflection angle, the scanning speed on the optical element 50 (lens array), and the length of the scanning path for one cycle on the optical element 50 (lens array). Good.

  Furthermore, in the above-described example, the irradiation device 60 emits the first to third coherent lights La, Lb, and Lc in three different wavelength ranges, and the first to third coherent lights La, In the example, Lb and Lc are primary color components for displaying white. However, the first to third coherent lights La, Lb, and Lc in each wavelength region do not need to be primary color components for displaying white. Moreover, the irradiation apparatus 60 does not need to irradiate the coherent light of three different wavelength ranges, For example, you may make it irradiate the coherent light of two different wavelength ranges. In this case, it is possible to illuminate the illuminated area with a color that cannot normally be displayed with coherent light from a single light source. In addition, with coherent light from a single light source, it is usually possible to display an image in a color that cannot be displayed, or display an image in a plurality of colors.

  Further, as already described with reference to FIG. 9 as a modified example of the basic form, the irradiation device 60 irradiates the optical element 50 with the combined light SL along the optical path of one light beam forming a virtual parallel light beam. You may do it. That is, the irradiation device 60 may irradiate each position of the hologram recording medium 55 of the optical element 50 with the combined light SL traveling in a certain direction. As a specific configuration, as shown in FIG. 9, in addition to the reflection device 66 described above, the scanning device 65 is a lens as a collimator that deflects the traveling method of the light reflected by the reflection device 66 in a certain direction. 67 may be included. Here, since the combined light SL including a plurality of coherent lights La, Lb, and Lc having different wavelength regions is incident on the lens 67, the lens 67 is achromatic from the viewpoint of preventing problems such as chromatic dispersion. It is preferable to use a lens.

5 Image 6 Scattering plate 10 Projection type image display device 15 Screen 20 Projection device 25 Projection optical system 26 Composite projection optical system 26a Cross dichroic prism 26b Lens 27 Guide devices 30, 30-1, 30-2, 30-3 Spatial light modulation Device 40 illumination device 50, 50-1, 50-2, 50-3 optical element 55, 55-1, 55-2, 55-3 hologram recording medium 58 hologram photosensitive material 60 irradiation device 61 light source mechanism 61a light source (first Light source) B
61b Light source (second light source) G
61c Light source (third light source) R
65, 65-1, 65-2, 65-3 Scanning device 66 Mirror device (reflection device)
66a Mirror (reflective surface)
LZ Illuminated area SL Synthetic light La Coherent light (first coherent light)
Lb coherent light (second coherent light)
Lc coherent light (third coherent light)

Claims (34)

A hologram recording medium capable of diffracting a first coherent light in a first wavelength region and a second coherent light in a second wavelength region different from the first wavelength region;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device illuminates an area where the first coherent light is diffracted by the hologram recording medium and overlaps at least partially, and the hologram recording from the irradiation device The irradiation device and the hologram recording medium are arranged so that the second coherent light incident on each position of the medium illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially.
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. Greater than the maximum angle formed by the two incident directions of the first coherent light incident on a point from various directions;
A plurality of the hologram recording media are provided corresponding to coherent light in each wavelength region, and the plurality of hologram recording media are arranged on a plane.
The irradiation device includes: a light source mechanism that generates combined light obtained by combining a plurality of coherent lights having different wavelength ranges; and a traveling direction of the combined light from the light source mechanism, and the combined light is converted into the hologram A scanning device adapted to scan over a recording medium,
The irradiation device irradiates the combined light so as to scan a plurality of hologram recording media in which the combined light is arranged side by side along a linear scanning path,
The length of the scanning path of the combined light on the hologram recording medium corresponding to the second coherent light is longer than the length of the scanning path of the combined light on the hologram recording medium corresponding to the first coherent light. apparatus. The hologram recording medium can diffract third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region;
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation apparatus and the hologram recording so that the third coherent light incident on each position of the hologram recording medium from the irradiation apparatus illuminates a region that is diffracted by the hologram recording medium and at least partially overlaps each other. Medium is placed,
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. Greater than the maximum angle formed by the two incident directions of the third coherent light incident on a point from various directions;
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. The illumination device according to claim 1, wherein the illumination device corresponds to the third primary color component on a longer wavelength side than the wavelength region.   The width of the hologram recording medium corresponding to the second coherent light along the direction parallel to the scanning path of the combined light corresponds to the first coherent light along the direction parallel to the scanning path of the combined light. The illumination device according to claim 1, wherein the illumination device is longer than a width of the hologram recording medium. The overlapping part in the region illuminated by the first coherent light and the overlapping part in the region illuminated by the second coherent light overlap each other,
A plurality of hologram recording media are provided corresponding to coherent light in each wavelength region,
4. The hologram recording medium corresponding to the second coherent light is disposed closer to the overlapping portion than the hologram recording medium corresponding to the first coherent light. The lighting device described in 1. A hologram recording medium capable of diffracting a first coherent light in a first wavelength region and a second coherent light in a second wavelength region different from the first wavelength region;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device illuminates an area where the first coherent light is diffracted by the hologram recording medium and overlaps at least partially, and the hologram recording from the irradiation device The irradiation device and the hologram recording medium are arranged so that the second coherent light incident on each position of the medium illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially.
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. Greater than the maximum angle formed by the two incident directions of the first coherent light incident on a point from various directions;
The overlapping part in the region illuminated by the first coherent light and the overlapping part in the region illuminated by the second coherent light overlap each other,
A plurality of hologram recording media are provided corresponding to coherent light in each wavelength region,
The illuminating device, wherein the hologram recording medium corresponding to the second coherent light is disposed closer to the overlapping portion than the hologram recording medium corresponding to the first coherent light. The irradiation device scans the hologram recording medium by changing a traveling direction of the coherent light from the plurality of light sources respectively generating the plurality of coherent lights having different wavelength ranges and the plurality of light sources. And a scanning device to
The illumination apparatus according to claim 4 or 5, wherein the plurality of coherent lights having different wavelength ranges are incident on the same scanning device from different directions, and the traveling directions thereof are changed in different directions.   The illumination according to claim 1, wherein a speed at which the second coherent light scans the hologram recording medium is faster than a speed at which the first coherent light scans the hologram recording medium. apparatus. Each coherent light periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent light is longer than the length of the constant scanning path on the hologram recording medium scanned by the first coherent light. The lighting device according to any one of Items 1 to 7. A hologram recording medium capable of diffracting a first coherent light in a first wavelength region and a second coherent light in a second wavelength region different from the first wavelength region;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device illuminates an area where the first coherent light is diffracted by the hologram recording medium and overlaps at least partially, and the hologram recording from the irradiation device The irradiation device and the hologram recording medium are arranged so that the second coherent light incident on each position of the medium illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially.
The maximum angle formed by the two incident directions of the second coherent light that comes to enter a certain point in the overlapping area in the illuminated area from various directions is in the overlapping area in the illuminated area. Greater than the maximum angle formed by the two incident directions of the first coherent light incident on a point from various directions;
Each coherent light periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent light is longer than the length of the constant scanning path on the hologram recording medium scanned by the first coherent light apparatus. The irradiation device is provided corresponding to each of a plurality of light sources that respectively generate a plurality of coherent lights having different wavelength ranges, and a coherent light from each light source, and changes a traveling direction of the coherent light from the corresponding light source. A plurality of scanning devices for allowing the coherent light to scan on the hologram recording medium,
Each of the plurality of scanning devices has a corresponding coherent light that vibrates on the hologram recording medium at a constant first direction frequency along the first direction and along a second direction that intersects the first direction. However, the traveling direction of the corresponding coherent light is changed so as to vibrate at a constant second direction frequency equal to or lower than the first direction frequency,
The ratio of the first direction frequency to the second direction frequency of the scanning device that changes the traveling direction of the second coherent light is the second value of the scanning device that changes the traveling direction of the first coherent light. The lighting device according to claim 8 or 9, wherein the lighting device is larger than a value of a ratio of the first direction frequency to a direction frequency. A hologram recording medium capable of diffracting a first coherent light in a first wavelength region and a second coherent light in a second wavelength region different from the first wavelength region;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium,
The first coherent light incident on each position of the hologram recording medium from the irradiation device illuminates an area where the first coherent light is diffracted by the hologram recording medium and overlaps at least partially, and the hologram recording from the irradiation device The irradiation device and the hologram recording medium are arranged so that the second coherent light incident on each position of the medium illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially.
A speed at which the second coherent light scans on the hologram recording medium is faster than a speed at which the first coherent light scans on the hologram recording medium;
The maximum angle formed by the two incident directions of each coherent light that comes to be incident from a variety of directions at a point in the overlapping portion of the illuminated region is the same among the plurality of coherent lights. Lighting device. The hologram recording medium can diffract third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region;
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation apparatus and the hologram recording so that the third coherent light incident on each position of the hologram recording medium from the irradiation apparatus illuminates a region that is diffracted by the hologram recording medium and at least partially overlaps each other. Medium is placed,
The speed at which the second coherent light scans on the hologram recording medium is faster than the speed at which the third coherent light scans on the hologram recording medium,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. The illumination device according to claim 11, wherein the illumination device corresponds to the third primary color component on a longer wavelength side than the wavelength region. A holographic recording medium capable of diffracting a second coherent light in a second wavelength range different from the first wavelength range;
An irradiation device that irradiates a plurality of coherent lights having different wavelength ranges so that the first coherent light and the second coherent light scan on the hologram recording medium. The first coherent light incident on each position illuminates a region that is diffracted by the hologram recording medium and overlaps at least partially, and the first coherent light incident on each position of the hologram recording medium from the irradiation device. The irradiating device and the hologram recording medium are arranged so that two coherent lights are each diffracted by the hologram recording medium and illuminate a region that overlaps at least partly,
Each of the plurality of coherent lights periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent is longer than the length of the constant scanning path on the hologram recording medium scanned by the first coherent,
The maximum angle formed by the two incident directions of each coherent light that comes to be incident from a variety of directions at a point in the overlapping portion of the illuminated region is the same among the plurality of coherent lights. Lighting device. The hologram recording medium can diffract third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region;
The irradiation device irradiates the third coherent light so as to scan the hologram recording medium,
The irradiation apparatus and the hologram recording so that the third coherent light incident on each position of the hologram recording medium from the irradiation apparatus illuminates a region that is diffracted by the hologram recording medium and at least partially overlaps each other. Medium is placed,
The third coherent light periodically scans a certain scanning path on the hologram recording medium,
The length of the constant scanning path on the hologram recording medium scanned by the second coherent is longer than the length of the constant scanning path on the hologram recording medium scanned by the third coherent,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. The lighting device according to claim 13, which corresponds to the third primary color component on a longer wavelength side than the wavelength region.   The illuminating device according to any one of claims 1, 2, 5, 9, and 11 to 14, wherein a plurality of the hologram recording media are provided corresponding to coherent light in each wavelength region.   The illumination device according to claim 15, wherein the plurality of hologram recording media provided corresponding to the coherent lights in the respective wavelength ranges are arranged on a certain plane.   The illuminating device according to claim 15, wherein the plurality of hologram recording media provided corresponding to the coherent lights in the respective wavelength ranges are arranged to overlap each other. The irradiation device includes: a light source mechanism that generates combined light obtained by combining a plurality of coherent lights having different wavelength ranges; and a traveling direction of the combined light from the light source mechanism, and the combined light is converted into the hologram A scanning device adapted to scan over a recording medium,
The said light source mechanism has a some light source which each produces | generates the coherent light of each wavelength range, and the synthetic | combination device which synthesize | combines the coherent light from these light sources, The 1, 2, 5, 9, and 11-11. The lighting device according to any one of 17.   The irradiation device is provided corresponding to each of a plurality of light sources that respectively generate a plurality of coherent lights having different wavelength ranges, and a coherent light from each light source, and changes a traveling direction of the coherent light from the corresponding light source. The illuminating device according to claim 1, further comprising: a plurality of scanning devices that allow the coherent light to scan the hologram recording medium. The irradiation device scans the hologram recording medium by changing a traveling direction of the coherent light from the plurality of light sources respectively generating the plurality of coherent lights having different wavelength ranges and the plurality of light sources. And a scanning device to
The plurality of coherent lights having different wavelength ranges are incident on the same scanning device from different directions, and the traveling directions thereof are changed in different directions, respectively. The lighting device according to claim 1.   The lighting device according to any one of claims 18 to 20, wherein each light source is generating the coherent light at different times. A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiating device illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other, and The irradiation apparatus and the light diffusing element are configured such that the second coherent light incident on each position of the light diffusing element is changed in a traveling direction by the light diffusing element and illuminates regions overlapping at least in part. Is placed,
A speed at which the second coherent light scans on the light diffusing element is faster than a speed at which the first coherent light scans on the light diffusing element;
The maximum angle formed by the two incident directions of each coherent light that comes to be incident from a variety of directions at a point in the overlapping portion of the illuminated region is the same among the plurality of coherent lights. Lighting device. The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The irradiation apparatus so that the third coherent light incident on each position of the light diffusing element from the irradiation apparatus illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other. And the light diffusing element is disposed,
A speed at which the second coherent light scans on the light diffusing element is faster than a speed at which the third coherent light scans on the light diffusing element;
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. The lighting device according to claim 22, wherein the lighting device corresponds to the third primary color component on a longer wavelength side than the wavelength region. A light diffusing element that changes the traveling direction of incident light;
Irradiating a plurality of coherent lights having different wavelength ranges so that the first coherent light in the first wavelength range and the second coherent light in the second wavelength range different from the first wavelength range scan on the light diffusion element. An irradiation device,
The first coherent light incident on each position of the light diffusing element from the irradiating device illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other, and The irradiation apparatus and the light diffusing element are configured such that the second coherent light incident on each position of the light diffusing element is changed in a traveling direction by the light diffusing element and illuminates regions overlapping at least in part. Is placed,
Each of the plurality of coherent lights periodically scans a certain scanning path on the light diffusing element,
The length of the constant scanning path on the light diffusing element scanned by the second coherent is longer than the length of the constant scanning path on the light diffusing element scanned by the first coherent,
The maximum angle formed by the two incident directions of each coherent light that comes to be incident from a variety of directions at a point in the overlapping portion of the illuminated region is the same among the plurality of coherent lights. Lighting device. The irradiation device irradiates a third coherent light in a third wavelength region different from the first wavelength region and the second wavelength region so as to scan the light diffusing element,
The irradiation apparatus so that the third coherent light incident on each position of the light diffusing element from the irradiation apparatus illuminates a region where the traveling direction is changed by the light diffusing element and at least partially overlaps each other. And the light diffusing element is disposed,
The third coherent light periodically scans a certain scanning path on the light diffusing element,
The length of the constant scanning path on the light diffusing element scanned by the second coherent is longer than the length of the constant scanning path on the light diffusing element scanned by the third coherent,
The first wavelength range corresponds to a first primary color component, the second wavelength range corresponds to a second primary color component on a longer wavelength side than the first wavelength range, and the third wavelength range corresponds to the second primary color component. The lighting device according to claim 24, wherein the lighting device corresponds to the third primary color component on the longer wavelength side than the wavelength region.   The lighting device according to any one of claims 22 to 25, wherein the light diffusing element is a lens array. The lighting device according to any one of claims 1 to 21,
A spatial light modulator disposed at a position illuminated by the coherent light incident and diffracted from each position of the hologram recording medium from the irradiation device. The lighting device according to any one of claims 22 to 26;
A projection device comprising: a spatial light modulator disposed at a position illuminated by the coherent light that is incident on each position of the light diffusing element from the irradiation device and whose traveling direction is changed;   The projection apparatus according to claim 27 or 28, further comprising a projection optical system that projects a modulated image obtained on the spatial light modulator onto a screen. The overlapping portions in the region illuminated by the coherent light diffracted by the hologram recording medium are located at different positions between the plurality of coherent lights,
A plurality of the spatial light modulators are provided corresponding to each of the plurality of coherent lights,
Each spatial light modulator is arranged so as to overlap with an overlapping part in the region illuminated by the corresponding coherent light,
28. The projection apparatus according to claim 27, further comprising a composite projection optical system that synthesizes and projects the modulated image obtained on each spatial light modulator. The overlapping portions in the region illuminated by the coherent light whose traveling direction is changed by the light diffusing element are located at different positions between the plurality of coherent lights,
A plurality of the spatial light modulators are provided corresponding to each of the plurality of coherent lights,
Each spatial light modulator is arranged so as to overlap with an overlapping part in the region illuminated by the corresponding coherent light,
29. The projection apparatus according to claim 28, further comprising a composite projection optical system that synthesizes and projects the modulated image obtained on each spatial light modulator. A projection device according to any one of claims 27 to 31,
And a screen on which a modulated image obtained on the spatial light modulator is projected. The lighting device according to any one of claims 1 to 21,
A screen illuminated by the coherent light incident on and diffracted from each position of the hologram recording medium from the irradiation device,
The overlapping portions in the region illuminated by the coherent light diffracted by the hologram recording medium overlap each other between the plurality of coherent lights,
The projection-type image display device, wherein the screen is arranged so as to overlap with an overlapping portion in an area illuminated by the plurality of coherent lights. The lighting device according to any one of claims 22 to 26;
A screen illuminated by the coherent light that is incident on each position of the light diffusing element from the irradiation device and whose traveling direction is changed, and
The overlapping portions in the region illuminated by the coherent light whose traveling direction is changed by the light diffusing element overlap each other among the plurality of coherent lights,
The projection-type image display device, wherein the screen is arranged so as to overlap with an overlapping portion in an area illuminated by the plurality of coherent lights.

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