JP2017219824A - Full-color high resolution computer-generated hologram display device, fabrication method of the same, and fabrication apparatus of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hologram display device that displays a full-color three-dimensional stereoscopic image which can be displayed/appreciated by using a super-high resolution computer-generated hologram and a color filter, and a fabrication method thereof.SOLUTION: A hologram display device according to the present invention includes: a metal film on which interference fringes is formed; a color filter constituted by combining color filter segments of a plurality of colors; and a reference light source which illuminates the metal film and the color filter. Interference fringes of the metal film are formed corresponding to individual color filter segments constituting the color filter, and a guard gap which guards illuminated reference light is provided for interference fringes of the metal film which correspond to an area where color filter segments of different colors are adjacent to each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hologram display device, a manufacturing method thereof, and a manufacturing device thereof, and more particularly to a full-color high-resolution computer-generated hologram display device, a manufacturing method thereof, and a manufacturing device thereof.

  In order to generate a three-dimensional stereoscopic image by color holography, it is necessary to record interference fringes on a recording material by irradiating an object with laser beams of three colors in a dark room in conventional optical holography. This shooting requires extremely high skill.

  Further, only real objects can be recorded and reproduced by the above-described methods, and non-existing virtual objects (for example, computer graphic data) or large objects that cannot be irradiated with laser light (for example, buildings) Is difficult to visualize.

  On the other hand, computer-generated holograms (Computer-Generated Holograms: CGH) have a feature that non-existent objects and scenes expressed by numerical data can be reproduced. Conventionally, a method using a color filter for colorization of CGH has been proposed. For example, Patent Document 1 discloses a method using a spatial light modulator and a color filter. However, in the current spatial light modulator, the display resolution is insufficient by three digits or more to obtain a high-quality three-dimensional stereoscopic image, and a high-quality image cannot be obtained even if a large-scale apparatus is used. Also, Patent Document 2 discloses a reproduction method using a color filter. However, the reproduction method is premised on the use of a coherent light source or a complicated optical circuit by a laser device. It is very difficult to create a possible hologram.

  On the other hand, the inventors of the invention according to the present application calculate an ultra-high resolution CGH of 10 billion pixels or more that can be actually displayed and appreciated, and etch a chromium film on a glass substrate to produce a high-contrast interference fringe. Thus, a high-quality 3D stereoscopic image is obtained by reflection or transmission reproduction using a simple LED light source. In fact, with these CGHs, images with a sense of depth and natural motion parallax that cannot be expressed by conventional stereoscopic video technology are reproduced (see Non-Patent Documents 1 to 3). However, since this image is obtained by monochromatic light, reproduction with a white light source or full color is difficult.

  Therefore, Non-Patent Document 4 discloses an apparatus for color reproduction by combining reproduction light of three holograms with an optical system. However, the actual display is difficult because the device becomes larger.

JP 2008-281774 A JP-A-8-201630 JP 2008-122668 A

K. Matsushima, et al., Appl. Opt. 48, H54-H63 (2009) K. Matsushima, et al., J. Electron. Imaging 21, 023002 (2012) Matsushima, HODIC Circular 32, No. 2, 31-40 (2012) Miyaoka, Matsushima, Nakahara 3D Image Conference 2014, P-13, (2014)

  The present invention is a full-color three-dimensional display that can be displayed and viewed with a non-coherent LED light source or white light source using a 10 billion pixel scale ultra-high resolution computer-generated hologram made of a high-contrast metal reflective film and a color filter. It is an object of the present invention to provide a hologram display device that displays a stereoscopic image and a manufacturing method thereof.

  Furthermore, the present invention relates to a method for manufacturing a hologram display device using a volume hologram generated by transfer, and a device for manufacturing the hologram display device, and a method for manufacturing a hologram display device that displays a full-color three-dimensional stereoscopic image. An object is to provide an apparatus.

The present invention has been made to achieve the above-described object. The hologram display device according to the present invention is
A metal film on which interference fringes are formed;
A color filter configured by combining color filter segments of a plurality of colors;
A reference light source for illuminating the metal film and the color filter,
The interference fringes of the metal film are formed corresponding to individual color filter segments constituting the color filter,
In the interference fringes of the metal film corresponding to the portions where the color filter segments of different colors are adjacent to each other, a guard gap for guarding the illuminated reference light is provided.

  By using the present invention, a full-color three-dimensional stereoscopic image that can be displayed and viewed is displayed using an ultrahigh-resolution computer-generated hologram with a scale of 10 billion pixels made of a high-contrast metal reflective film and a color filter. A hologram display device can be obtained. Further, by utilizing the present invention, a full-color high-resolution computer-generated hologram display device that can be mass-produced and has excellent wavelength selectivity and angle selectivity can be transferred using an ultra-high-resolution computer-generated hologram and a color filter. Can be obtained.

It is a figure which shows the preparation methods of the hologram display apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows typically the structure of the hologram display apparatus which concerns on the 1st Embodiment of this invention. Fig.3 (a) is a figure which shows the example of the spectral characteristic of fluorescent substance type white LED which permeate | transmitted the color filter twice. FIG. 3B is a diagram illustrating an example of spectral characteristics of a multi-chip color LED that has passed through the color filter twice. It is a figure for demonstrating the positional relationship of the color filter and interference fringe layer in the hologram display apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the pixel block structure of the color filter in the hologram display apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the outline | summary of the drawing method by the lithography using a laser drawing apparatus or an electron beam drawing apparatus. It is a figure for demonstrating the positional relationship of the color filter and interference fringe layer in the hologram display apparatus which concerns on the 1st Embodiment of this invention. FIG. 8A shows an interference fringe layer without a guard gap. FIG. 8B is a diagram showing an interference fringe layer provided with a guard gap. FIG. 9A is a diagram showing the effect of the guard gap in a configuration used as a reflection hologram display device. FIG. 9B is a diagram showing the effect of the guard gap in a configuration used as a transmission hologram display device. It is a figure which shows the color filter in which a some segment forms a horizontal stripe. It is a figure which shows the reflection type hologram display apparatus using the amplitude modulation of light, and the reflection type hologram display apparatus using the phase modulation of light. FIG. 12A is a simplified diagram showing a conventional photographic (recording) form of a transmission hologram. FIG. 12B is a simplified diagram showing a conventional imaging (recording) form of a reflection hologram. FIG. 12C is a simplified diagram showing a photographing (recording) form of a Denniske volume hologram. FIG. 13A is a schematic longitudinal sectional view of a thin hologram. FIG. 13B is a schematic longitudinal sectional view of a volume hologram (thick hologram). It is the schematic which shows the mode of reproduction | regeneration of the metal film high-resolution original edition CGH used by preparation by transcription | transfer of the Denniske type volume hologram which concerns on 3rd Embodiment. It is the schematic which shows the mode of transcription | transfer to the recording material of the original CGH of metal film high resolution. It is a figure which shows the manufacturing method and manufacturing apparatus of a full-color high-resolution computer-synthesizing hologram display device which makes the dennisk type | mold volume hologram produced by transcription | transfer of a 1st form a full-color thing. It is a figure which shows the manufacturing method and manufacturing apparatus of a full-color high-resolution computer-synthesizing hologram display which make the Denniske type | mold volume hologram produced by transcription | transfer of a 2nd form full-color thing. It is a figure which shows the manufacturing method and manufacturing apparatus of a full-color high-resolution computer-synthesizing hologram display device which makes the dennisk type | mold volume hologram produced by transcription | transfer of a 3rd form full-color thing. It is a figure which shows the manufacturing method and manufacturing apparatus of a full-color high-resolution computer-synthesizing hologram display which make the Denniske type | mold volume hologram produced by transcription | transfer of a 4th form into a full color thing.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[First embodiment]
1. Configuration of Hologram Display Device FIG. 2 is a diagram schematically showing the configuration of the hologram display device according to the first embodiment of the present invention. FIG. 1 is a diagram showing a method for manufacturing a hologram display device according to the first embodiment of the present invention.

1.1. Configuration of Color Filter System The hologram display device shown in FIG. 2 displays a full-color computer-generated hologram (CGH) using the color filter 4 and the single interference fringe layer 2. In the production of the color filter type full-color computer-generated hologram display device according to the first embodiment, first, the single-plate interference fringe layer 2 is spatially divided into RGB blocks (2r, 2g, 2b) to interfere with each color. Draw stripes. As will be described later, the interference fringes are formed in the metal layer 8. Subsequently, color filters (4r, 4g, 4b) of colors corresponding to each of the RGB blocks are bonded and juxtaposed on the metal film on which the interference fringes are formed. The color filter type full-color computer-generated hologram display device according to the first embodiment performs full-color reproduction by irradiating white light, which is reference light, to the juxtaposed interference fringe layer 2 and the color filter 4. This white light is emitted from a white light source (reference light source) 100. Each color reproduction illumination light that has passed through (or passed through) the color filter 4 illuminates the corresponding block, thereby reproducing each color image. In general, since the hologram has a characteristic that can be reproduced even from a part of the interference fringes, it is possible to reproduce the color by synthesizing the images of the respective colors.

  The high-precision color filter 4 can be created by various methods. For example, it can be created by a digital silver salt laser printing technique in which image data is directly drawn on a reversal film using three primary color lasers. By this method, various color filter patterns can be easily and accurately created.

1.2. Configuration of White Light Source First, the white light source 100 that emits white light as reference light will be described. The RGB illumination lights in the white light source 100 are preferably in a narrow band. This is because if the band is wide, the image (holography) is blurred due to the occurrence of chromatic aberration in each color. In general, a color filter has a wide band and low wavelength selectivity. Therefore, it is desirable that the light source be a laser (ie, monochromatic light) if possible. However, it is not desirable to use a laser for display and viewing. Therefore, in the hologram display device according to the present embodiment, a narrow band of each illumination light is realized by using a multichip color LED light source (pseudo white light source). 3A shows an example of the spectral characteristics of a phosphor type white LED that has passed through the color filter twice, and FIG. 3B shows the spectral characteristics of the multi-chip color LED that has passed through the color filter twice. An example is shown. 3 (a) and 3 (b), it can be confirmed that the wavelength band of each color is narrower in the multi-chip full color LED than in the phosphor type white LED. In a multi-chip full color LED, three LED chips of RGB are enclosed in one package. As an example of the specifications of the multichip full color LED, there are a view angle of 116 deg and a luminance of 970 to 1940 mcd (simultaneous lighting).

1.3. Next, the positional relationship between the color filter 4 and the interference fringe layer 2 will be described. Conventionally, in the case of a monochromatic reflection type CGH, as shown in FIG. 4A, a high reflectivity film 2 (such as a Cr film) in which interference fringes are formed on the back surface of the light incident surface of the glass substrate 10, In addition, a low reflectance film 14 (such as a CrO film) that protects the glass substrate and the interference fringe layer is disposed. In order to attach the color filter 4 to the configuration shown in FIG. 4A, it is necessary to attach it to the front surface of the glass substrate 10 as shown in FIG. 4B. However, due to the gap generated between the color filter 4 and the reflectance film 2, an error occurs particularly near the boundary of the RGB segments. For this reason as well, it has been conventionally considered that full color reproduction of CGH using a color filter is difficult.

  Based on the above, in the hologram display device according to the present embodiment, as shown in FIG. 4 (c), the Cr film (high reflectance film 2) on the back side of the glass substrate 10 that has not been used conventionally. The color filter 4 is attached in close contact with the surface. At this time, the protective film (low reflectance film) may be removed or the film thickness may be reduced.

1.4. Pixel Block Configuration in Color Filter Next, (color) filtering in units of pixel blocks will be described. When the color filter 4 is attached to the interference fringe layer 2 on the surface of the high reflectivity film (Cr film), it is impossible to apply one color filter to one pixel of the interference fringe. This is because the pixel pitch of the interference fringes is as very fine as 0.8 to 1.0 μm, whereas the color filter cannot create a pattern on the micron order. Therefore, as shown in FIG. 5, the (RGB) segment (4r, 4g, 4b) of the color filter is applied to each pixel (pixel) block (2r, 2g, 2b) of the interference fringe 16.

1.5. Formation of interference fringes In the hologram display device according to the present embodiment, the interference fringes are formed on the metal film layer by lithography using a laser drawing device or an electron beam drawing device. FIG. 6 is a diagram showing an outline of a lithography drawing method. A Cr film 8 ′ and a resist layer 6 are laminated on the glass substrate 10 (see FIG. 6A). First, as shown in FIG. 6A, the resist layer 6 is exposed by laser irradiation or electron beam irradiation 12. Next, as shown in FIG. 6B, the exposed resist layer 6 is removed. Next, as shown in FIG. 6C, the exposed Cr film 8 is etched, and finally the remaining resist layer 6 is removed as shown in FIG. 6D. The layer for forming the interference fringes is not limited to the metal film 8 such as the Cr film 8 ', and the method for forming the interference fringes is not limited to lithography. Interference fringes may be formed on a member that can be processed to give a fine pattern and that has a high contrast.

1.6. Method for Manufacturing Hologram Display Device A method for manufacturing a hologram display device according to the present embodiment will be described. FIG. 1 is a diagram showing a method for manufacturing a hologram display device according to the first embodiment of the present invention. First, using RGB (light emission) spectrum data data (and color filter transmittance spectrum data) (104) as input data, the design wavelength of each RGB CGH (Computer-Generated Hologram) is optimized. The calculation is performed by the computer (step S02). At this time, after the data relating to the colors of the respective RGB LEDs, for example, the data (106) relating to the hue and the brightness, is also inputted, the calculation for optimizing the design wavelength of each of the RGB CGHs is performed (step S02). preferable.

  Next, the optimized design wavelength data for each RGB CGH (see step S02) and the three-dimensional scene model data (102) are used as input data, and the CGH interference fringes for each of RGB are first created. Then, calculation is performed by a computer (step S04, step S06, and step S08), and CGH interference fringe pattern data for each of RGB is generated.

  That is, in steps S02 to S08, the interference fringe data in the computer-generated hologram for each primary color reference light is calculated to generate CGH interference fringe pattern data for each of RGB (step S09). If the CGH interference fringe pattern data for each of RGB is appropriately generated, the calculation of the interference fringe data in the computer-generated hologram for each primary color reference light may be different from steps S02 to S08.

  In general, color filters do not have high production accuracy. Further, as described above, the resolution of the color filter is lower by one digit or more than the physical resolution (1 μm or less, 25000 dpi or more) of the interference fringes on the high reflectance film (Cr film) surface. Based on these facts, position error information (data) (108) of the color filter is input to the computer. Based on the position error information (data) (108) of the color filter, the computer generates position correction data of interference fringes by color filter patterns, for example, stripes and guard gaps (step S10). The “stripe” and “guard gap” will be described later.

  The computer inputs the CGH interference fringe pattern data (see steps S04, S06, and S08) for each of the RGB generated by calculation, and the interference fringe position correction data by the stripe and guard gap, and the computer performs high reflection. Data after the synthesis of the interference fringe pattern actually formed on the rate film (Cr film) is generated and output (step S12).

  The steps from S02 to S12 are performed by the computer based on the input data.

  Further, as shown in FIG. 6, the interference fringe layer 2 is formed on the metal high reflectivity film (Cr film) 8 by the lithography apparatus (step S14). The high reflectivity film (Cr film) 8 on which the interference fringe layer 2 is formed is bonded to the color filter 4 (see FIGS. 5 and 4).

  In this way, the hologram display device (110) for full color CGH is manufactured.

1.7. Next, a description will be given of a guard gap formed in an interference fringe. In principle, full color reproduction by a hologram display device is possible if a color filter is accurately mounted on the surface of a high reflectivity film (Cr film). However, in practice, it is impossible to bond the high reflectance film (Cr film) 8 on which the interference fringe layer 2 is formed and the color filter 4 without causing an error as shown in FIG. Yes, as shown in FIG. 7B, the positions of the interference fringe layer 2 and the color filter 4 shift. In FIG. 7B, the color filter 4 is slightly shifted below the paper surface with respect to the interference fringe layer 2. As described above, when the positions of the interference fringe layer 2 and the color filter 4 are misaligned, the error portion is irradiated with illumination light having a wavelength different from that at the time of calculation of interference fringes (and at the time of recording), thereby causing chromatic aberration. This occurs and the reproduced image deteriorates.

  For example, since the illumination light indicated by the first arrow from the top in FIG. 7B is illumination light having a wavelength of blue (B), it must be reflected by the interference fringe for blue (B). . However, if the color filter 4 and the interference fringe layer 2 are bonded to each other as shown in FIG. 7B, the illumination light indicated by the top arrow in FIG. 7B is red (R). It has been reflected by the interference fringes for. Here, chromatic aberration occurs, and the reproduced image deteriorates. The same applies to the illumination light indicated by the second to sixth arrows from the top in FIG.

  In order to cope with such degradation of the reproduced image, in this embodiment, as shown in FIG. 8B, a gap 18 is provided at the boundary between the interference fringe blocks of each color to give an allowable amount for the error. Hereinafter, the gap 18 is referred to as a guard gap (Guard Gap) (FIG. 8A is a diagram showing the interference fringe layer 2 in which no guard gap is provided). When the guard gap 18 is provided in the hologram display device shown in FIG. 7B in which chromatic aberration has occurred, an interference fringe having a structure as shown in FIG. Since the interference fringes transmit illumination light having a wavelength different from that at the time of recording, which causes chromatic aberration, the illumination light does not affect the reproduction light.

  For example, the blue (B) wavelength illumination light indicated by the first arrow from the top of FIG. 9A is illuminated by the first arrow from the top of FIG. 7B if there is no guard gap 18. It will be reflected by interference fringes for red (R) like light. Since the guard gap 18 is provided here as shown in FIG. 9B, the blue (B) wavelength illumination light is transmitted to the glass substrate 10, and this blue (B). Illumination light having a wavelength does not cause chromatic aberration (does not affect reproduction light).

  Here, the configuration shown in FIG. 9A is used as a reflection type hologram display device, and does not generate chromatic aberration by transmitting light in a boundary region (guard gap). On the other hand, the configuration shown in FIG. 9B is used as a transmissive hologram display device, and prevents chromatic aberration from occurring by blocking (not transmitting) light in the boundary region (guard gap). . For example, the blue (B) wavelength illumination light indicated by the first arrow from the top in FIG. 9B passes through the interference pattern for red (R) without the guard gap 18 and then passes through the interference fringe for FIG. The light passes through the color filter 4b for blue (B) like the illumination light indicated by the first arrow from above (b). Since the guard gap 18 is provided here as shown in FIG. 9B, the blue (B) wavelength illumination light is blocked at the end of the glass substrate 10, and thus this blue ( B) Illumination light having a wavelength does not cause chromatic aberration (does not affect reproduction light).

  Thus, since the reflection hologram display device and the transmission hologram display device have different roles of the guard gap, it is necessary to design according to the application.

  The inventor has also found that the reproduced image deteriorates if the guard gap width is too wide. As a result of repeating the simulation and optical reproduction, the inventor has determined that the optimum value is 100 μm for the stripe width and 50 μm for the guard gap width (the stripe will be described later).

1.8. Next, a configuration example of a plurality of segments in the color filter will be described. As shown in FIG. 5, the (RGB) segment (4r, 4g, 4b) of the color filter 4 is applied to each pixel block (2r, 2g, 2b) of the interference fringe 16. That is, the color filter 4 according to the present embodiment is composed of a plurality of segments. A segment adjacent to one segment is different from the (one) segment.

  In the color filter 4 shown in FIGS. 2, 5, and 8, the plurality of segments form vertical stripes, but the configuration of the plurality of segments is not limited to this. For example, as shown in FIG. 10, a plurality of segments may form a horizontal stripe. When forming horizontal stripes, it is only necessary to consider errors in the vertical direction, so there is an advantage that the alignment between segments is easy. Furthermore, in the first place, the parallax in the horizontal direction is important in a stereoscopic image. In other words, since it is desirable that errors are not generated as much as possible in the parallax in the horizontal direction, in a hologram display device using a color filter, it can be said that the reproduced image looks better when the stripes formed by the segments are horizontal rather than vertical. .

  Further, the configuration of the plurality of segments of the color filter may be other than the vertical stripe and the horizontal stripe. Although not shown, a delta may be configured.

[Second Embodiment]
2. Other Configurations of Hologram Display Device The hologram display device according to the present invention is not limited to that of the first embodiment, and various changes and modifications can be incorporated. Below, especially the example of the other structure of a reflection type hologram display apparatus is demonstrated. The rest of the configuration of the reflection type hologram display apparatus below is basically the same as that of the reflection type hologram display apparatus according to the first embodiment, and the difference between them will be mainly described.

  In general, a reflection-type full-color computer-generated hologram display device with a color filter often has a problem that an image is not so bright. The reasons for this include the fact that the manufacturing error of the color filter is not necessarily small and that the light is transmitted at least twice through the color filter, which has a transmittance that is not so high in the reflection hologram.

  One solution to the above problem is the use of phase modulation. FIGS. 11B-1 and 11B-2 are schematic views of a reflection hologram display device using the concept of phase modulation. On the other hand, FIGS. 11A-1 and 11A-2 are schematic diagrams of a reflection-type hologram display device using light amplitude modulation.

  FIG. 11 (a-1) is a diagram schematically showing opaque interference fringes in a reflection hologram display device that utilizes amplitude modulation of light. In the reflection type hologram display device using the amplitude modulation of light, it is relatively easy to manufacture the opaque interference fringes, but there is a problem that the use efficiency of light is low and the image becomes dark. On the other hand, FIG. 11 (b-1) is a diagram schematically showing transparent interference fringes in a reflection hologram display device using phase modulation of light. In a reflection hologram display device using phase modulation of light, the light utilization efficiency is increased and the image is brightened.

  FIG. 11A-2 is a diagram schematically showing a transverse section of a reflection-type hologram display device using light amplitude modulation. FIG. 11B-2 is a diagram schematically showing a transverse section of a reflection type hologram display device using phase modulation of light. The reflection hologram display device shown in FIG. 11A-2 is configured by laminating the glass substrate 10, the interference fringe layer 2, and the color filter 4 as already described. Here, the interference fringe layer 2 is formed of a metal layer.

  On the other hand, the reflection hologram display device shown in FIG. 11B-2 is configured by laminating the glass substrate 10, the metal film 32, the photoresist layer 22, and the color filter 4. Here, the photoresist layer 22 forms interference fringes. Since the transparent photoresist layer 22 forms interference fringes, the light utilization efficiency is increased and the image is brightened.

[Third embodiment]
The third embodiment uses a volume hologram generated by transfer. In other words, the third embodiment uses the principle of a volume hologram, particularly the principle of a Denniske volume hologram.

3.1. Advantages of Thin and Thick Holograms and Volume Type Hologram (Thick Hologram) The advantages of thin and thick holograms and volume type holograms will be described with reference to FIGS.

3.1.1. Thin Hologram First, FIG. 12 (a) is a simplified diagram showing a conventional transmission hologram recording (recording) configuration. In the transmission hologram recording (recording) form shown in FIG. 12A, the light emitted from the laser 52 is branched in two directions by the beam splitter 54. One of the branched laser beams is applied to the object 64 (to be recorded) via the mirror 56 and the lens 60. The other of the branched laser beams is directly irradiated onto the recording material 70 via the mirror 58, the lens 62a, and the lens 62b.

  The object light 68 that is the reflected light from the object 64 and the reference light 66 that is directly irradiated onto the recording material 70 interfere with each other on the recording material, but a hologram whose intensity distribution is recorded by the recording material becomes a hologram. . During reproduction, the recording material 70 is irradiated with the same reproduction illumination light as the reference light 66. At this time, when the recording material 70 is viewed from the side opposite to the reproduction illumination light, the object image is reproduced at the point where the recording material 70 is transmitted. Therefore, the hologram recorded by the photographing (recording) form shown in FIG. 12A is a transmission hologram.

  Further, as in the photographing (recording) form shown in FIG. 12A, since the reference light 66 and the object light 68 are irradiated to the recording material 70 from the same direction (same side), the interference fringes are recorded on the recording material. 70 is generated on the surface. Such a hologram is generally referred to as a “thin hologram” as opposed to a “thick hologram” described later.

3.1.2. Thick hologram (volume hologram)
Next, FIG. 12B is a simplified diagram showing a conventional reflection (hologram) form of the reflection hologram. In the reflection hologram photographing (recording) mode shown in FIG. 12B, the light emitted from the laser 52 is branched in two directions by the beam splitter 54. One of the branched laser beams is applied to the object 64 (to be recorded) via the mirror 56 and the lens 60. The other of the branched laser beams is directly irradiated onto the recording material 70 from the side opposite to the object 64 via the two mirrors (mirror 58 and mirror 59), the lens 62a and the lens 62b.

  The object light 68 that is the reflected light from the object 64 and the reference light 66 that is directly irradiated onto the recording material 70 from the side opposite to the object 64 interfere with each other on the recording material, but the intensity distribution is recorded on the recording material. What is recorded by the above becomes a hologram. During reproduction, the recording material 70 is irradiated with the same reproduction illumination light as the reference light 66. At this time, when the recording material 70 is viewed from the side of the reproduction illumination light, the object image is reproduced by reflection of the reproduction illumination light. Therefore, the hologram recorded by the photographing (recording) form shown in FIG. 12B is a reflection hologram.

  12B, the recording material 70 is irradiated from the opposite direction (reverse side) of the reference beam 66 and the object beam 68, so that the interference fringes are generated. Recording material 70 is recorded three-dimensionally in the depth direction. Such a hologram is generally referred to as a “thick hologram”, and is also referred to as a “volume hologram”, in contrast to the aforementioned “thin hologram”.

3.1.3. Advantage of Volume Type Hologram FIG. 13A is a schematic longitudinal sectional view of a thin hologram. In a thin hologram, interference fringes are generated two-dimensionally on the surface of the recording material 70. On the other hand, FIG. 13B is a schematic longitudinal sectional view of a volume hologram (thick hologram). In the volume hologram, the interference fringes are generated three-dimensionally in the depth direction of the recording material 70. In this case, the interference fringes are recorded as a large number of layered structures substantially parallel to the hologram surface. Since reproduced light is generated by multiple interference between fringes, it is known that volume holograms are superior in wavelength selectivity and angle selectivity compared to thin holograms.

  Then, assuming a “volume-type computer-generated hologram” in which the volume-type hologram and the computer-generated hologram (CGH) described above are combined, the following (1-a) to (2-b), etc. Benefits.

(1) Advantages of computer-generated hologram (CHG) itself (1-a) No real object is required for creating a hologram. A hologram can be created only from the three-dimensional model as data.
(1-b) Data can be stored and transferred as digital data.

(2) Advantages of volume hologram (2-a) It has excellent wavelength selectivity, and even when white reproduction illumination light is used, only the same wavelength as that during recording is selected and reproduced. That is, it can be reproduced with white reproduction illumination light.
(2-b) It has excellent angle selectivity and can be reproduced even when the light source of the reproduction illumination light is large.

  By the way, a volume type in which interference fringes are generated three-dimensionally in the depth direction of the recording material depending on a normal method for creating a computer-generated hologram (CHG), for example, a method using a printer or a method using a fine processing technique. A hologram cannot be generated. Therefore, in the third embodiment, the “volume-type computer-generated hologram” assumed above is realized by transferring the original CGH (computer-generated hologram) (interference fringes) to the volume-type hologram. Since the “volume type computer-generated hologram” according to the third embodiment is generated by transfer, mass production is facilitated.

3.1.4. Denniske-type Volume Hologram Here, the Denniske-type volume hologram will be described. FIG. 12C is a simplified diagram showing a photographing (recording) form of a Denniske volume hologram. In the imaging (recording) form of the Denniske type volume hologram shown in FIG. 12C, the light that exits the laser 52 and passes through the mirror 56 and the lens 60 passes through the recording material 70 (is desired to be recorded). Is irradiated. The light emitted from the laser 52 and passing through the mirror 56 and the lens 60 also functions as the reference light 66. Therefore, the object light 68 reflected from the object 64 interferes with the reference light 66, and interference fringes are recorded on the recording material 70, thereby producing a Denniske hologram. In the production of the denishuku type hologram, the object light 68 is incident on the recording material 70 from the side opposite to the reference light 66, so that the denishuku type hologram becomes a volume hologram.

  It is known that a Denniske-type hologram that captures (records) a volume hologram has advantages such as a very simple recording optical system, resistance to disturbances such as vibration, and the ability to easily photograph large objects. . Therefore, in the third embodiment, a hologram display device is manufactured by transferring an original CGH (computer-generated hologram) (interference fringe) to a Denniske-type volume hologram.

3.2. Preparation of Dennisque Volume Hologram by Transfer The principle and schematic procedure of transfer of a Dennisku volume hologram according to the third embodiment will be described. FIG. 14 is a schematic view showing a state of reproduction of a metal film high-resolution original CGH used for production by transfer of a Denniske-type volume hologram according to the third embodiment. The metal film high-resolution original CGH (interference fringes) is produced by laser lithography, and the interference fringes themselves have a high reflectivity, enabling high-efficiency reproduction as a reflection type. .

  The metal film high-resolution master CGH (interference fringes thereof) is formed on the surface of the chromium film 88. Further, the surface of the chromium film 88 is covered and covered with the glass substrate 90. When the reproduction illumination light 82 is irradiated from the reproduction illumination light source 80 onto the surface of the glass substrate 90 and the chromium film 88, the reproduction light 84 accompanied with the reproduction image 86 is given to the observer 94 on the reproduction illumination light source 80 side. It is generated (reproduced) and arrives.

  Next, FIG. 15 is a schematic view showing a state of transfer of the metal film high-resolution master CGH to the recording material 105. In FIG. 15, a recording material 105 is attached to a glass substrate 90 that closely covers the surface of a chromium film 88 on which a metal film high-resolution original plate CGH (interference fringes) is formed. Further, the pinhole position of the spatial filter 98 of the reproduction illumination light source 96 is set so as to coincide with the center position of the virtual reference light spherical wave for creating the original CGH.

  When the reproduction illumination light 82 is irradiated from the reproduction illumination light source 96 onto the surface of the chromium film 88 on which the original CGH (interference fringes) is formed, the reproduction light 84 accompanied with the reproduction image 86 is generated as described with reference to FIG. Generated (reproduced). This reproduction light becomes the object light 103, and the reproduction illumination light 82 from the reproduction illumination light source 96 simultaneously becomes the reference light 101, and interference fringes are recorded on the recording material 105. This is a transfer of the metal film high-resolution master CGH. At the same time, this is the same as recording the object light 68 light wave of the object 64 placed on the back surface of the recording material 70 in the imaging (recording) form of the Denniske volume hologram shown in FIG. It is. Therefore, what is produced by transfer is a volume hologram.

  As the recording material 105 shown in FIG. 15, a silver salt film, a photopolymer, or the like is used. In FIG. 15, the recording material 105 is affixed to a glass substrate 90 that closely adheres to the surface of the chromium film 88 on which the metal film high-resolution master CGH (interference fringes) is formed. The film may be affixed to the surface of the chromium film 88 on which the high-resolution original CGH (interference fringes) is formed.

  As described above, the volumetric hologram of Denisek type produced by transfer utilizes the fact that the high-resolution metal film CGH produced by laser lithography enables high-efficiency reproduction as a reflection hologram. Yes. Since it can be transferred to a volume hologram by one step of single exposure, the recording optical system is simple, the resistance to vibration is extremely strong, and a hologram excellent in wavelength selectivity and angle selectivity can be generated. Become.

  Therefore, the Denniske volume hologram produced by transfer can be a transfer CGH that can be reproduced by various light sources such as a white light source and a large light source. Even when a white reproduction light source is used, only the wavelength of light (reproduction illumination light, reproduction light, and reference light) used during transfer is reproduced. From this, as will be described below, it is possible to develop a Denniske volume hologram produced by transfer on a full-color high-resolution computer-generated hologram display device.

3.3. Full color high-density computer-generated hologram display device of Denishuku type volume hologram manufactured by transfer using FIG. 16, FIG. 17, FIG. 18 and FIG. Explain the development to.

3.3.1. Method for Producing Full Color High-Resolution Computer-Generated Hologram Display Device of First Embodiment FIG. 16 is a full-color high-resolution computer-generated hologram display in which the Denniske volume hologram produced by transfer according to the first embodiment is full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of an apparatus. First, the original CGH • R110r, the original CGH • G110g, and the original CGH • B110b represent CGH interference fringes of R (red), G (green), and B (blue), respectively. First, the original CGH / R110r is transferred to the volume hologram R (red) 112r by using the R (red) laser as reproduction illumination light and reference light (in FIGS. 14 and 15) (recording after recording). Create material R (red)). Next, the master CGH · R110g is transferred to the volume hologram G (green) 112g by using a G (green) laser as reproduction illumination light and reference light (a recording material G (green) after recording is created). ). Further, the original CGH · R110b is transferred to the volume hologram B (blue) 112b by using B (blue) laser as reproduction illumination light and reference light (recording material B (blue) after recording is created). .

  Finally, the recording materials R, G, and B after recording are superposed to produce a full-color high-resolution computer-generated hologram display device. In the manufacturing method according to the first embodiment, three master CGHs and three transfer holograms are used, and the number of transfer shots is three. This manufacturing method is characterized by easy alignment. Of course, the production order of the recording materials R, G, and B generated by the transfer may be different from that shown in FIG. The order of superimposition of the recording materials R, G and B after recording may be different from that shown in FIG.

3.3.2. Method for Producing Full-Color High-Resolution Computer-Generated Hologram Display Device of Second Embodiment FIG. 17 is a full-color high-resolution computer-generated hologram display in which the Denniske volume hologram produced by transfer according to the second embodiment is full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of an apparatus. First, as in FIG. 16, the original CGH / R110r, the original CGH / G110g, and the original CGH / B110b represent CGH interference fringes of R (red), G (green), and B (blue), respectively. Yes.

  First, the original CGH / R110r is transferred to the volume hologram R (red) 112r by using the R (red) laser as reproduction illumination light and reference light (in FIGS. 14 and 15) (recording after recording). Create material R (red)).

  Next, the original CGH / G110g is transferred onto the recording material R (red) of the volume hologram R (red) 112r, using the G (green) laser as reproduction illumination light and reference light, and the volume hologram RG (red) , Green) 112 rg recording material RG (red, green) is produced.

  Further, the volume hologram RG (red, green) 112 rg is overlaid on the recording material RG (red, green) and the original CGH / B110b is transferred using the B (blue) laser as the reproduction illumination light and the reference light. The recording material RGB (red, green, blue) of RGB (red, green, blue) 112 rgb is created. In the manufacturing method according to the second embodiment, three master CGHs and one transfer hologram are used, and the number of transfer shots is three. This manufacturing method is characterized in that multiple exposure is performed and alignment is difficult. In the manufacturing method according to the second embodiment, the transfer order by the R, G, and B lasers may be different from that shown in FIG.

3.3.3. FIG. 18A is a full-color high-resolution computer in which the Denniske volume hologram produced by transfer according to the third embodiment is a full-color one. It is a figure which shows the manufacturing method and manufacturing apparatus of a synthetic hologram display apparatus. The recording material 120 of the original CGH and the color filter 118 shown in FIG. 18A are each a metal film on which the interference fringe layer 2 according to the first embodiment (shown in FIG. 2) is formed. And it corresponds to the color filter 4. Therefore, the recording material 120 of the original CGH includes RGB interference fringe blocks and guard gaps between the interference fringe blocks (see FIG. 8B). The color filter 118 includes a color filter (RGB) segment corresponding to the interference fringe block (see FIG. 2).

  First, by using the recording material 120 of the original CGH and the color filter 118, the R (red) laser is used as reproduction illumination light and reference light (in FIGS. 14 and 15), so that the original CGH is converted into a volume hologram R Transferred to (red) 122r (creates recording material 124 (red) after recording). At this time, the red block portion of the original CGH is transferred.

  The schematic positional relationship among the recording material 120 of the original CGH, the color filter 118, the recording material 124 after recording, and the laser for transfer is as shown in FIG. The same applies to the following procedures.

  Next, using the recording material 120 of the original CGH and the color filter 118, the G (green) laser is used as the reproduction illumination light and the reference light, so that it is superimposed on the recording material 124 of the volume hologram R (red) 122r, The master CGH is transferred to produce the recording material 124 (red, green) of the volume hologram RG (red, green) 122 rg. At this time, the green block portion of the original CGH is transferred.

  Further, by using the recording material 120 of the original CGH and the color filter 118, the B (blue) laser is used as the reproduction illumination light and the reference light so as to overlap the recording material 124 of the volume hologram RG (red, green) 122 rg. Then, the master CGH is transferred to produce the recording material 124 (red, green, blue) of the volume hologram RGB (red, green, blue) 122 rgb. At this time, the blue block portion of the original CGH is transferred. In the manufacturing method according to the third embodiment, one original CGH, one color filter, and one transfer hologram are used, and the number of transfer shots is three. This production method is characterized in that multiple exposure is performed, alignment is easy, and a higher quality hologram than the original is obtained. The color filter can be reused. In the manufacturing method according to the third embodiment, the order of transfer by the R, G, and B lasers may be different from that shown in FIG.

3.3.4. FIG. 19A is a full-color high-resolution computer in which the Denniske volume hologram produced by transfer according to the fourth embodiment is a full-color one. It is a figure which shows the manufacturing method and manufacturing apparatus of a synthetic hologram display apparatus. Similarly to the manufacturing method according to the third embodiment, the recording material 120 of the original CGH and the color filter 118 shown in FIG. 19A are respectively related to the first embodiment (shown in FIG. 2). ) Corresponds to the metal film on which the interference fringe layer 2 is formed and the color filter 4. Therefore, the recording material 120 of the original CGH includes RGB interference fringe blocks and guard gaps between the interference fringe blocks (see FIG. 8B). The color filter 118 includes a color filter (RGB) segment corresponding to the interference fringe block (see FIG. 2).

  In the manufacturing method according to the fourth embodiment, an RGB laser (mixed of R (red) laser, G (green) laser, and B (blue) laser) using the recording material 120 of the original CGH and the color filter 118 is used. Is transferred to the volume hologram RGB (red, green, blue) 122 rgb (recording material 124 after recording (red, green). , Blue))). In the manufacturing method according to the fourth embodiment, RGB three-wavelength lasers are superimposed on the same axis. In the manufacturing method according to the fourth embodiment, all of the red block portion, the green block portion, and the blue block portion of the original CGH are transferred.

  The schematic positional relationship between the recording material 120 of the original CGH, the color filter 118, the recording material 124 after recording, and the laser for transfer is as shown in FIG. In the manufacturing method according to the fourth embodiment, one original CGH, one color filter, and one transfer hologram are used, and the number of transfer shots is one. This production method is characterized in that multiple exposure is performed, alignment is easy, and a higher quality hologram than the original is obtained. The color filter can be reused. In addition, since the number of transfer shots is one, the manufacturing method according to the fourth embodiment is more for mass production.

2 ... interference fringe layer, 4 ... color filter, 6 ... resist layer, 8 ... metal film, 8 '... Cr film, 10 ... glass substrate, 16 ... interference fringe , 18 ... guard gap, 22 ... photoresist layer, 32 ... metal film, 64 ... object, 70 ... recording material, 94 ... observer, 82 ... reproduction illumination light 84... Reproducing light, 101... Reference light, 103.

Claims (15)

A metal film on which interference fringes are formed;
A color filter configured by combining color filter segments of a plurality of colors;
A reference light source for illuminating the metal film and the color filter,
The interference fringes of the metal film are formed corresponding to individual color filter segments constituting the color filter,
A hologram display device provided with a guard gap for guarding the reference light to be illuminated in the interference fringes of the metal film corresponding to portions where the color filter segments of different colors are adjacent to each other.   The hologram display device according to claim 1, wherein the interference fringes are formed based on a computer-generated hologram. The hologram display device according to claim 1, wherein each color filter segment corresponds to a plurality of pixels in the interference fringes. The hologram display device according to claim 1, wherein the guard gap transmits reference light. The hologram display device according to claim 1, wherein the guard gap blocks reference light. The hologram display device according to claim 1, wherein the reference light source is a multi-chip color LED light source. The hologram display device according to claim 1, wherein the metal film and the color filter are formed in close contact with each other. The hologram display device according to claim 1, wherein the plurality of color filter segments form a color filter pattern. A metal film,
A photoresist layer formed with interference fringes on the metal film;
Furthermore, a color filter configured by combining a plurality of color filter segments on the photoresist layer;
A reference light source that illuminates the metal film, the photoresist layer, and the color filter, and the interference fringes of the photoresist layer are formed corresponding to individual color filter segments constituting the color filter,
In the interference fringes of the photoresist layer corresponding to the portions where the color filter segments of different colors are adjacent to each other, a guard gap for guarding the illuminated reference light is provided,
A hologram display device in which the guard gap transmits reference light.   The hologram display device according to claim 1 or 9, wherein an interference fringe is formed on a member capable of processing a fine pattern in place of the metal film and having a high contrast of the applied pattern. Calculating interference fringe data in a predetermined computer-generated hologram;
Calculating correction data of the position of the color filter and correction data of the position of the guard gap in the interference fringe based on the position error information of the color filter;
Generating interference fringe pattern composite data based on the correction data of the position of the color filter and the correction data of the position of the guard gap in the interference fringe;
Forming interference fringes on the film based on the combined data of the interference fringe patterns;
A method for producing a hologram display device, comprising the step of bonding a film having interference fringes and a color filter together. Design of computer-generated hologram for primary color reference light emitted by each primary color LED constituting multichip color LED based on emission spectrum data of each primary color LED constituting multichip color LED and transmittance spectrum data of color filter A step of optimizing the wavelength;
Calculating interference fringe data in the computer-generated hologram for each primary color reference light based on the model data of the three-dimensional scene and the design wavelength data in the optimized computer hologram;
Calculating correction data of the position of the color filter and correction data of the position of the guard gap in the interference fringe based on the position error information of the color filter;
Generating interference fringe pattern synthesis data based on interference fringe data in computer-generated holograms for each primary color reference light, color filter position correction data, and guard gap position correction data in interference fringes;
Forming interference fringes on the film based on the combined data of the interference fringe patterns;
A method for producing a hologram display device, comprising the step of bonding a film having interference fringes and a color filter together.   The method for producing a hologram display device according to claim 11 or 12, wherein an interference fringe is formed on a member capable of performing a fine pattern in place of the film and having a high contrast of the applied pattern. A step of preparing a metal film on which an original CGH (computer-generated hologram) is recorded and a color filter formed by combining a plurality of color filters, wherein the original CGH of the metal film is the color filter A guard that guards the reproduction illumination light that is illuminated in the original CGH of the metal film, which is formed corresponding to the individual color filter segments constituting the color filter segments and corresponds to the adjacent portions of the color filter segments of different colors A step with a gap, and
Illuminating the metal film and the color filter with reproduction illumination light from a reproduction illumination light source to reproduce the reproduction light of the original CGH;
And transferring the original CGH by recording a volume hologram on a recording material using the reproduction light as object light and the reproduction illumination light as reference light. A metal film on which an original CGH (computer-generated hologram) is recorded;
A color filter configured by combining color filters of a plurality of colors;
A reproduction illumination light source for illuminating the metal film and the color filter to reproduce the original CGH;
Recording material,
The original CGH of the metal film is formed corresponding to each color filter segment constituting the color filter, and the original CGH of the metal film corresponding to a portion where the color filter segments of different colors are adjacent to each other A guard gap is provided to guard the playback illumination light to be illuminated,
Illuminating the illumination light from the reproduction illumination light source on the metal film and the color filter to reproduce the reproduction light of the original CGH,
Furthermore, the original CGH is transferred by recording a volume hologram on a recording material using the reproduction light as object light and the reproduction illumination light as reference light.
A device for manufacturing a hologram display device.