JPH10232592A - Picture recording device and picture reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to observe a three-dimensional picture of high quality in a broader observation area even with a small area of recording material by forming information of interference between an object beam and a reference beam passed through a waveguide tube type optical system on a surface of a recording medium and recording picture information based on the object beam from an object beam forming means on the recording medium. SOLUTION: An object OB is illuminated with a light flux from an object beam forming means, and an object beam CL from the object OB is made to reach a photosensitive material 1 through a waveguide tube type optical system 3 of which an exit light part 3b has a smaller aperture diameter compared with that of an incident part 3a. A reference beam RL from the reference beam forming means is made incident on the photosensitive material 1. Interference fringes of the object beam OL and the reference beam RL are recorded on the photosensitive material for making a hologram. In a case of reproduction, the hologram 2 is irradiated with illumination light of a same wavelength and wavefront as the original reference beam RL, and a reproduced beam SL from the hologram 2 is magnified larger than the incident part 3a by using the waveguide tube type optical system 3 in reverse to the time of recording, for guiding the light beam to an observer, and a reproduced picture 10 of the object OB is observed by a formed wavefront.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus and an image reproducing apparatus for recording and reproducing three-dimensional image information, for example, a dynamic image or a static image using a hologram as a recording material on which image information is recorded. This is suitable for recording and reproducing.

[0002]

2. Description of the Related Art Conventionally, a holographic technique has been used.
Various methods for recording and reproducing a dimensional object have been proposed. As the most common method, a three-dimensional object is illuminated with coherent light from a laser, and its diffuse reflected light (object light) interferes with coherent light (reference light) from laser light coming from another direction, The interference fringes (hologram interference fringes) are recorded on a recording material to form a hologram, and the same wavefront (reconstructed light) as the original object light even when the hologram is irradiated with illumination light having the same wavelength and the same wavefront as the reference light. ), That is, a method of reproducing an object image.

This method requires a photosensitive material or the like that resolves a high spatial frequency to form hologram interference fringes, and the reproduced image is limited to a still image. On the other hand, a technology that enables reproduction of a three-dimensional moving image while using holography technology is disclosed in, for example, JP-A-64-84793, JP-A-6-186901, and JP-A-6-24.
No. 2715, for example.

Japanese Patent Application Laid-Open No. Sho 64-84993 discloses FIG.
Liquid crystal dot matrix display element 33-1 as shown in FIG.
There is disclosed a real-time hologram reproducing apparatus using a hologram. In the drawing, a microprocessor 33-5 and a video control circuit 33-4 generate an interference fringe pattern enabling a desired three-dimensional image reproduction, and the driver circuit 33-2 converts the interference fringe pattern into a liquid crystal dot matrix element 33-. 1
Draw as a light and dark pattern on top. This is irradiated with laser light generated from the laser light emitting circuit 33-3, and the observer observes from the direction A to observe a stereoscopic image. Further, a three-dimensional moving image is obtained by dynamically changing an interference fringe pattern drawn on the liquid crystal dot matrix element 33-1.

[0005] JP-A-6-186901 and JP-A-6-186901
JP-A-242715 discloses a three-dimensional moving image display device using a still image hologram as shown in FIG. In the figure, 34-1 is a laser light source, 34-2 is a magnifying lens, 34-3 is a hologram, 34-4 is a motor,
34-5 is a control device. The laser light emitted from the laser light source 34-1 is magnified by the lens 34-2, and then enters a predetermined area of the hologram 34-3 as reference light.

As shown in FIG. 34, the hologram 34-3 is pasted on a disk 35-0 together with a plurality of other holograms 35-1 to 35-3, and is configured to be rotatable by a motor 34-4. In this configuration, the reference light is sequentially incident on each hologram by the rotation of the motor 34-4.

Each hologram 35-1, 35-2, 35-
3 are point images 35-4 at different positions in the three-dimensional space,
Exposure is performed to reproduce 35-5 and 35-6. If the number of holograms is increased and the number of reproducible point images is increased, it is possible to reproduce, for example, a rectangular box or the like in the three-dimensional space. Control circuit 34-5
An image signal indicating which of the plurality of point images is to be emitted and a rotation angle signal of the hologram disk are inputted to the laser light source 34 when the point image is to be emitted.
-1 is turned on, and the laser light source 34-1 is controlled not to be turned on when a point image should not be emitted. By executing these series of processes within human afterimage time,
A desired object corresponding to the image signal is displayed three-dimensionally. In addition, a moving image is obtained by moving an image created every afterimage time.

[0008]

In the hologram reproducing apparatus shown in FIG. 32, first, the resolution of a spatial modulation element for displaying an interference fringe pattern is considerably lower than the resolution of a conventional photosensitive material, and The observation area of the reproduced image is narrowed because the diffraction angle of the light cannot be increased so much.
In general, the effective area of a spatial light modulator capable of forming a fine interference fringe pattern, which is used in a real-time hologram reproducing apparatus, cannot be increased so much that the size of a reproduced image is limited. The spatial modulation element capable of forming a fine interference fringe pattern, such as that used in a hologram reproducing apparatus, generally has extremely low diffracted light utilization efficiency, and fourthly, the information amount of the interference fringe pattern displayed on the spatial modulation element Is too large to handle the processing capability of the system for calculating and processing the interference fringe pattern.

In the three-dimensional moving image display device shown in FIG. 33, the trade-off is made between the size of the reproduced image and the amount of information of the recordable image with respect to the effective area of each hologram area to be recorded. ing. That is, if the effective area is small, the reproduced image is limited to a small one, and if the effective area is large, the amount of information that can be recorded is reduced.

According to the present invention, when recording image information on a recording material and reproducing the image information recorded on the recording material,
An image recording apparatus capable of observing a high-quality stereoscopic image (three-dimensional image) in a wide observation area even with a recording material having a relatively small area by using an appropriately set waveguide type optical system; It is intended to provide an image reproducing device.

[0011]

According to the image recording apparatus of the present invention, there is provided an image recording apparatus comprising: (1-1) an inner peripheral portion of an object light based on an object light generating means for generating coherent object light, wherein an exit aperture is smaller than an entrance aperture. Forming interference information between the object light and the reference light from the reference light generating means on the recording material surface via the waveguide type optical system having the surface as a reflecting surface, based on the object light from the object light generating means; It is characterized in that image information is recorded on the recording material.

In particular, (1-1-1) the waveguide type optical system has a conical tube, a trumpet tube, or a horn tube;
The waveguide type optical system has a lens group, (1-1
-3) The image information is three-dimensional image information.

According to the image reproducing apparatus of the present invention, there is provided (2-1) illumination of the same wavelength and the same wavefront as the reference light from a lighting means on a recording material on which image information is recorded by utilizing interference between the object light and the reference light. Irradiating light, and guiding reproduction light generated from the recording material to a waveguide type optical system having an inner peripheral surface having a larger exit opening as compared with an entrance opening and having a reflective surface; The image information is reproduced from a light beam passing through the image information.

In particular, (2-1-1) a plurality of the recording materials are provided on a drivable substrate, and the driving means drives the substrate, so that at least one of the plurality of recording materials becomes a recording material. (2-1-2) performing intensity modulation of the illumination light emitted from the illumination means by the control means based on the displacement information of the substrate, wherein the illumination light is emitted from the illumination means. (2-1-3) The image information is three-dimensional image information.

The image recording / reproducing apparatus according to the present invention comprises: (3-1)
The recording material on which the image information is recorded by using the image recording device having the configuration (1-1) is used to reproduce the image information recorded on the recording material by using the image reproducing device having the configuration (2-1). It is characterized by:

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic view of a main part of a first embodiment of the present invention. 1A shows the time of recording image information (at the time of creating a hologram), and FIG. 1B shows the time of reproducing image information (at the time of observing an object image recorded on the hologram).

In FIG. 1A, the object OB is illuminated with a light beam (coherent light) from an object light generating means (not shown). At this time, the object light OL from the object OB reaches the photosensitive material 1 through the waveguide type optical system 3 in which the opening diameter of the emission part 3b is smaller than the opening diameter of the incidence part 3a. On the other hand, the reference light RL from the reference light generating means is incident on the photosensitive material 1. Then, an interference fringe between the object light OL and the reference light RL is recorded on the photosensitive material 1 to create a hologram. Reference numeral 4 denotes a wavefront based on the object light OL.

Reference numeral 2 in FIG. 1B denotes a hologram created by the system shown in FIG. 1A. At the time of reproduction in FIG. 1B, the hologram 2 is irradiated with the illumination light IL having the same wavelength and the same wavefront (including the opposite phase wavefront) as the original reference light RL. Then, by using the waveguide type optical system 3 used for recording the reproduction light SL from the hologram 2 in the opposite direction to that for recording, the light is expanded from the incident part 3a and guided to the observer side, and formed at this time. The reproduced image IO of the object OB is observed by the wavefront.

FIG. 2 is a schematic diagram showing a conventional case where image information such as a three-dimensional image is recorded on a recording material 1 to form a hologram. As shown in the figure, in the conventional hologram preparation, the reference light RL and the object light O
L is recorded to create a hologram.

The hologram 2 recorded on the recording material 1
Is reproduced, the hologram 2 has the original reference light R
Illumination light I having the same wavelength and the same wavefront as L (including an antiphase wavefront)
L was irradiated and the reproduction light PL was directly observed. In this case, as shown in FIG. 3, of the images from the hologram 2, those that enter both eyes of the observer are each eye and the hologram 2.
Is limited to the region connecting the ends of Further, the existence region of the image which can be stereoscopically viewed, including the recognition of the binocular parallax, is limited to a hatched portion in the drawing. For this reason, if the size of the three-dimensional image to be reproduced is to be increased, the size of the hologram 2 must be increased.

On the other hand, in the present embodiment, as shown in FIG. 1, a waveguide type optical system (hereinafter also referred to as “optical system”) 3.
Is used to record and reproduce the object image. At this time, the size of the reproduced image IO does not depend on the size of the hologram 2,
It depends on the diameter of the image-side (observer-side) incident part 3a of the optical system 3. In particular, the size of the hologram 2 is reduced by making the diameter of the emission part (hologram side) 3b of the optical system smaller than the diameter of the incidence part (observer side) 3a.

In this embodiment, the hologram 2 and the optical system 3
When the image is recorded / reproduced in combination with the above, even if the optical system 3 has aberration, the optical system 3 records the wavefront including the aberration on the hologram, and reproduces it through the original optical system 3. Therefore, the image can be reproduced with no aberration.

As is apparent from FIG. 1, the object light OL that reaches the photosensitive material 1 at the time of recording a hologram is not the light reflected and diffused on the surface of the object OB, but has already passed through the optical system 3 and is optically reflected. It has a wavefront 4 'that has undergone wavefront conversion.
The aberration and the imaging effect of the optical system 3 are folded into the wavefront 4 'as a kind of the above-mentioned wavefront conversion, and the amplitude / phase information of the wavefront 4' on the photosensitive material 1 including all of them is recorded. Are recorded as interference fringes with the reference light RL. The illumination light IL of the hologram 2 basically uses illumination light having the same wavelength and the same wavefront (including an opposite phase wavefront) as the reference light RL at the time of recording.

Since the hologram 2 thus reproduced has a property of reproducing the object light at the time of recording without aberration, the hologram 2 reproduced under such a condition converts the illumination light into a light beam having the wavefront 4 '. This light beam is reversed in the optical system 3 placed at the same position as at the time of recording to perform an inverse conversion of the optical wavefront conversion at the time of recording, and the light beam having the wavefront 4 for reproducing the original object OB is obtained. Is to happen.

If a plurality of holograms for reproducing a point image are prepared in the manner described above and are sequentially replaced in the optical path, a plurality of point images can be reproduced before and after in time. In the present invention, in particular, the diameter of the emission part (hologram side) 3b of the optical system for image reproduction is changed to the incidence part (observer side) 3a.
, The area of one hologram for image reproduction is reduced, and a large number of holograms for image reproduction can be integrated and recorded at high density. The plurality of holograms for image reproduction are dynamically switched at high speed to make it appear as if a large number of images in a three-dimensional space are simultaneously reproduced by the afterimage effect.

In particular, as shown in FIG. 4, each image is set as a point image 41, and a set of the point images 41 formed at predetermined intervals in a predetermined three-dimensional space is reproduced to obtain an arbitrary three-dimensional image. The image can be reproduced.

FIG. 5 is a block diagram showing the configuration of a three-dimensional image display apparatus for integrating and recording a plurality of holograms according to the first embodiment, switching and reproducing each hologram, and reproducing an arbitrary three-dimensional image. Such a device is roughly divided into four parts: a three-dimensional image information control unit 51, a pulse beam forming unit 52, a beam conversion unit 53, and an image reproducing optical system 54.

The stereoscopic image information control unit 51 receives the position information signal from the beam conversion unit 53 and outputs a luminance information signal to the pulse beam forming unit 52. The pulse beam forming unit 52 includes:
A pulse-like light beam whose intensity is modulated at a high frequency in accordance with the luminance information signal is formed, and the beam converter 53 modulates the phase of the light beam at high speed for each pulse beam. The image reproducing optical system 54 sequentially forms the converted beam as an image in a three-dimensional space.

Thus, the speed of the beam conversion and the intensity modulation is sufficiently high and synchronized, so that an observer observing from a predetermined direction of the image reproducing optical system 54 can form an aggregate of a plurality of images by an afterimage effect. Can be observed.

Next, features of the first embodiment of the present invention will be described.

In the present embodiment, in order to make the most of the features of the aberration-free imaging of the hologram 2 and the integrated recording, the object light is efficiently focused on the recording area when recording the image as an optical system for reproducing the image. The waveguide type optical system 3 is used. FIG. 6 shows a conical tube 5 which is an example of a waveguide type optical system used in the present embodiment and has an inner peripheral side surface 5c as a reflection surface. The conical tube 5 is a conical tube molded of metal, glass, plastic, or the like, and the inner peripheral side surface 5c is a smooth reflecting surface that reflects light.

For this reason, as shown in FIG. 7, when the object light OL is made to enter from the opening 5a of the conical tube 5 having the larger diameter,
As shown in FIG. 7, the light travels backward while being reflected multiple times on the inner peripheral side surface 5c of the conical tube 5, and emerges from the opening 5b of the conical tube 5 having a smaller diameter. The photosensitive material 1 is disposed near the opening 5b having the smaller diameter, and interference fringes with the reference light RL are recorded, and information on the object light OL is recorded as a hologram 2 in a region as small as the opening 5b. doing.

Although the conical tube 5 itself has no image forming function, the conical tube 5 is arranged at the same position as that for recording when reproducing the hologram and has the same wavelength as that of the reference light RL.
The hologram 2 is illuminated with light having the same wavefront (including the opposite phase wavefront), and the original image of the object is reproduced through the conical tube 5.

If the distance between the optical system and the hologram is large at the time of recording, the light emitted from the opening on the hologram side spreads, making it difficult to record the hologram in a small area. It is desirable to make the distance between the hologram and the hologram as short as possible.

FIG. 8 is a schematic view of a main part of an image reproducing optical system using the waveguide type optical system of the present embodiment. The three-dimensional image information control unit 51 is configured by the computer 6. The computer 6 obtains a position information signal from the beam conversion unit 53, obtains position information of a reproducible image point, and outputs a corresponding luminance information signal to the pulse beam forming unit 52. The pulse beam forming section 52 has a light source 7 and a light beam transmittance control section 8. In order to enhance the imaging performance, the light source 7 having a high spatial coherency is used. For example, LE
D, a semiconductor laser or the like is used.

In this embodiment, the light source 7 is a single color L in the visible region.
An ED point light source is used, and a light beam from the light source is collimated into a parallel light beam. The light beam transmittance control unit 8 is arranged on the beam optical path using a high-frequency light modulation element such as an AOM (acoustic optical element) or an EO (electro-optical device). The high-frequency light modulation element 8 controls the beam transmittance in accordance with the luminance information signal output from the computer 6.

However, when the light source 7 itself uses a device capable of modulating the intensity at a high frequency, such as a semiconductor laser, the light intensity of the light source can be directly controlled in accordance with the luminance information signal. No rate controller 8 is required.

The light beam emitted from the pulse beam forming section 52 enters the beam converting section 53. Beam converter 53
Is a disk-shaped hologram array plate 10 in which a plurality of holograms recorded so as to reproduce a point image as described above are arranged side by side;
Hologram array plate displacing means 9 for displacing the hologram array at high speed and periodically.

In the present embodiment, a motor is used as the hologram array plate displacement means 9 so that the hologram array plate 10 can be rotated at a high speed.

In the example of FIG. 8, a large number of transmission holograms are arranged along the circumferential direction (here, H (1), H (2), H (2), ...
Handle with the number H (n). ). The displacement of the motor 9 is detected by a motor position detection encoder.
It is transmitting to the computer 6. Thus, the computer 6 derives the displacement of the hologram array plate 10 from the displacement of the motor 9. The timing at which the center of an arbitrary hologram H (k) (k is a natural number, 1 ≦ k ≦ n) on the hologram array plate 10 comes on the optical axis of the pulse beam is detected.

Further, the computer 6 accurately detects the timing at which a desired point image is reproduced, derives the luminance of the point image from three-dimensional image information given in advance, and transmits the light beam transmittance control unit 8 or the light source. 7, a luminance information signal is transmitted to control the luminance of the point image.

Thus, only at the moment when the center of the hologram H (k) is on the optical axis of the pulse beam, the pulse beam is made incident on the hologram to reproduce the point image, and otherwise, the pulse beam is not generated. To prevent the generation of unnecessary light.

For the above-described reason, the optical system 3 for image reproduction has the same arrangement as that for recording, the diameter of the incident side 3b is as small as the incident beam, and the diameter of the exit side 3a is a general display. A waveguide type optical system having the size of a screen is used.

In the present embodiment, the hologram is switched at high speed in order to reproduce an arbitrary three-dimensional image.
The device is designed to prevent the observer from perceiving the flicker of the point image by generating an afterimage effect. For example, when the hologram array plate 10 makes one round, the holograms are arranged so that all the point images are reproduced, and the number of rotations of the motor 9 is set to 20 to 30 or more per second, and the corresponding point images are set. Is performed so that the observer does not feel the flicker of the point image due to the afterimage effect.

The computer 6 holds the information of the three-dimensional image to be reproduced as a set of the coordinates (x, y, z) of the point image and the luminance L (x, y, z) of the point image. The luminance information signal is transmitted while checking the displacement amount of the hologram array plate 10 to enable reproduction of an arbitrary three-dimensional image without flicker.

The components of the three-dimensional image display device of the present embodiment can be replaced with other components as necessary, thereby increasing the applicability and versatility. An example is shown below.

(A) Hologram Array Plate The purpose of using the hologram array plate 10 in the present invention is to "collect and mount a plurality of small area holograms and switch their positions at high speed". If so, changes to the following embodiments are also effective.

(A1) Shape of Hologram The shape of the hologram integrated and mounted is not limited to a circular shape as shown in FIG. For example, in order to increase the effective area, a fan-shaped hologram 2a as shown in FIG. 9 or a polygonal shape may be used.

(A2) Types of hologram In the example shown in FIG. 8, a transmission hologram is used. However, there is no problem if a reflection hologram is used.
Further, in the above example, an on-axis hologram is used. However, when the on-axis hologram is difficult to copy or when the 0th-order light of the diffracted light is easily superimposed on the reproduced image, FIG. As shown in FIG. 10, the incident direction of the illumination light is inclined with respect to the optical axis of the optical system 3 for image reproduction.
An is-type hologram 2b may be used. At this time, also at the time of recording a hologram, reference light obliquely incident is used similarly to illumination light.

(A3) Shape of Hologram Array Plate The shape of the hologram array plate itself may be replaced with something other than a disk depending on the required specifications. For example,
The holograms 2 may be arranged one-dimensionally on a long plate 11 as shown in FIG. 11, and may be connected to a linear motor 12 that drives linearly reciprocally along the longitudinal direction. Also, a method of arranging holograms on something other than the plate can be applied as long as the above object is satisfied.
For example, as shown in FIG. 12, a method in which the holograms 2c are arranged on a tape and driven by a roller 13 and a motor 9 is applicable. Also, as shown in FIG. 13, a method in which holograms 2c are arranged on the side surface of a drum-shaped rotating body T1 and driven by a motor 9 like a plate can be applied.

(B) Image Reproduction Optical System (Waveguide Optical System) The purpose of the image reproduction optical system (waveguide optical system) of the present invention is to obtain a reproduced image larger than the hologram area. ,
Another object of the present invention is to efficiently collect object light during hologram recording. As long as this object is achieved, a change to an embodiment other than the side reflection cone tube 5 is also effective. However, in order to achieve the above object, the following conditions should be satisfied.

(B1) The opening on the hologram side is smaller than the opening on the object (reproduced image) side.

(B2) Most of the object light entering the optical system from the opening on the object (reproduced image) side reaches the opening on the hologram side.

The above condition (b1) is a problem of the shape of the optical system, and it is necessary that one of the two apertures is large and the other is small. The condition (b2) also largely depends on the shape of the optical system.

Next, the shape of the image reproducing optical system which is considered to be effective in the present invention will be described.

(B3) Improvement of Conical Optical System Since the waveguide type optical system focuses light to a minute area by using multiple reflection on the side surface, depending on the shape of the optical system, light may be transmitted even in the middle. May return to the object side. For example, as shown in FIG. 14, a light beam from a point light source 15 is passed through a conical side reflector (inner peripheral reflector) 14 to the recording material 1.
Consider a case where hologram recording is performed on a hologram. In the side reflector 14 shown in FIG. 14, since the slope of the side surface with respect to the rotational symmetry axis 16 is considerably large, of the light rays emitted from the point light source 15, those reflected at the point A each time the reflection is repeated, the semi-emission angle with respect to the reflecting surface As θ increases, the reflection angle at the reflection point B is substantially a right angle, and at the reflection point C exceeds the right angle, so that the light ray returns to the original direction. At this time, since this light beam does not reach the photosensitive material 1, the point light source 15
Is not recorded in the hologram.

On the other hand, as shown in FIG. 15, when a conical side reflector 17 having a smaller apex angle (elongated as a whole shape) is used, the slope of the side surface with respect to the rotational symmetry axis 16 is small, so that a point light source is used. Of the light rays emitted from the light source 15, those reflected at the point A also reach the photosensitive material 1 by multiple reflection. Thereby, the information of the point light source 15 is hologram-recorded.

As can be seen from FIG. 14, the reflection angle θ with respect to the reflecting surface increases each time the object light is repeatedly reflected on the side surface of the side reflector 14, so that the light does not return to the original direction. To achieve this, the number of reflections may be reduced. Therefore, as shown in FIG. 16, the object light easily reaches the photosensitive material 1 from the side reflector 14 having a short overall length and a small side gradient with respect to the rotational symmetry axis 16.
However, in the case of this shape, the opening 14b on the hologram side becomes large and the area of the hologram recording area becomes large, so that the hologram integration effect tends to be slightly reduced.

From the above, as for the shape of the side reflector 14, when the length of the rotationally symmetric axis 16 is LX and the opening diameters on the incident side and the exit side are LY1 and LY2, for example, 0.5 <LY1 / LX <1 0.01 <LY2 / LY1 <0.1

(B4) Trump-Shaped Optical System A trumpet-shaped side reflector 18 as shown in FIG. 17 is also applicable as a waveguide type optical system. In the trumpet-shaped side reflector 18, the gradient of the side surface with respect to the rotationally symmetric axis 16 becomes smaller as approaching the opening on the hologram side (θ ₁ > θ ₂ > θ _{3 in the} figure). Therefore, the rate of increase of the reflection angle of the incident light is smaller than that of the above-mentioned conical side reflector, and it is difficult for the light to return to the original direction, so that the object light can be efficiently collected. This is effective as the optical system for image reproduction of the present invention.

As shown in FIG. 18, a tube shape is formed near the opening 19a on the object (image) side, and a conical shape is formed in the middle portion 19b.
In the vicinity of the opening 19c on the hologram side, the compound side reflector 19 having a trumpet shape also has a high light-collecting efficiency of the object light and is effective as an image reproducing optical system.

(B5) Horn-Shaped Optical System One of the optical instruments for efficiently condensing light is a Wood optical trap 20 as shown in FIG. 19 (reference: written by Masao Tsuruta). "Light pencil"). This was devised to produce the darkest possible observation background during various optical measurements. Twist the glass tube to the shape of a horn as shown in Fig. 19 while gradually reducing the diameter of the glass tube. , With black paint applied to the outside. Light incident from the entrance surface 20a of the tube having such a shape is extremely unlikely to return to the original direction, and most of the light is guided to the narrow portion 20c at the tip. FIG. 19 shows the principle of the optical trap applied to the image reproducing optical system of the present invention.

FIG. 20 shows an example in which a horn-shaped waveguide type optical system 20 is used as an image reproducing optical system. FIG. 20 shows FIG.
The difference is that an optical system 20 having the shape shown in FIG. 19 is used in place of the conical optical system 3 described above, and the other configuration is the same. A reflection film is formed on the inner surface or the outer surface of the optical system. A small opening 20b is provided in the narrow portion of the tip of the optical trap, and the hologram H is arranged near the small opening 20b. Regarding the shape of the optical system 20, an optimum shape for efficiently condensing the object light is obtained in advance by computer simulation or the like.

When an optical system 20 as shown in FIG. 20 is used, the light-collecting effect in the y-axis direction in the figure is large, but the light-collecting effect in the x-axis direction may be reduced. Is an optical system 20 that is spirally wound as shown in FIG.
If d is used, it is possible to provide a configuration having a light-collecting effect on light incident from any direction.

(B6) Synthesizing System with Lens System FIG. 22 shows a combination of various waveguide type optical systems as described above and a conventional optical system 21 to improve the light collecting effect for image reproduction. It is a schematic diagram of an optical system. FIG. 22 shows an image reproducing optical system in which a conical side reflector 5 and a convex lens 21 are combined. The convex lens 21 has a function of making the incident angle α of the object light incident on the conical side reflector 5 smaller. This makes it difficult for the incident light to return to the original direction. Of course, in order to achieve an improvement in the light condensing effect, a composite optical system using the above-mentioned other waveguide type optical system other than the conical shape and the conventional optical system may be used.

Next, a second embodiment of the present invention will be described. In the present embodiment, a so-called RGB color of red (R), green (G), and blue (B) is used as a light source to achieve full color reproduction. Next, a specific method of full color conversion will be described.

In the first method, as shown in FIG.
Holograms HR, HG, H in which beams of each color are arranged in three rows
This is a method in which the light beams are independently made to enter B, respectively. At this time, the holograms HR, H on the hologram array plate 10
The arrangement of G and HB is as shown in FIG.

Also, utilizing the multiplex recording property of the hologram,
As shown in FIG. 25, a method in which three beams are simultaneously incident on one hologram region H from different directions, and a beam of each wavelength is converted into a desired wavefront is also applicable.

Further, as shown in FIG. 26, it is also possible to apply a method in which the beams after the respective color beams are converted by the individual holograms HR, HG, HB are combined by the dichroic mirror 22.

Next, a third embodiment of the present invention will be described. A feature of the present embodiment is that the number of images that can be recorded and reproduced is increased. A first method for increasing the number of images that can be recorded / reproduced is a method of increasing the number of holograms by more efficiently integrating holograms.

FIG. 27 illustrates the specific method. The feature of this method is that, as shown in FIG. 28, the hologram arrays H (1) to H (n) have holograms arranged spirally like pits of a CD-ROM. In order to perform beam conversion using the hologram array plate 10, an incident beam is guided to a desired position, and an exit beam is guided to an image reproducing optical system.

Thus, as shown in the figure, the tracking mirror 23 is provided on both the incident side and the exit side of the hologram array plate 10, and guides the beam as required. The tracking mirror 23 is constituted by a galvanometer mirror, and its displacement information is transmitted to the computer 6 and contributes to derivation of a luminance information signal of a point image.

Since the light emitted from the image reproducing optical system 3 becomes a light beam which easily spreads at a stretch, a waveguide type tracking pipe 24 as shown in FIG. 29 is connected between the image reproducing optical system 3 and the photosensitive material. It is effective to perform beam tracking in the same manner at the time of recording and reproducing a hologram while operating at the same time.

A second method for increasing the number of images that can be recorded / reproduced is to scan a beam with a hologram in FIG.
As shown in (1), two-dimensional scanning within one plane defined by the optical axis 16 of the reproducing optical system 3 and a straight line perpendicular to the optical axis is limited, and the rotational scanning around the optical axis is optically performed. To express three-dimensional information. That is, the three-dimensional image represented by this method has position information and luminance information expressed in a cylindrical coordinate system.

FIG. 31 is a schematic diagram specifically illustrating this method. Although the basic configuration is the same as that of the above-described embodiment, the image rotator 25
Is inserted, and is rotated about the optical axis of the image reproduction optical system 3 and the hologram H by the motor 9 via the roller 26 and the belt 27. The image rotator 25 is a device that is inserted into the optical system to rotate the image forming position around the optical axis. The displacement of the image rotator 25 is detected by an encoder attached to the motor 9 and sent to the computer 6. The image rotator 25 makes one rotation while one hologram is on the optical axis, and the hologram array plate 10
When rotated, a method that enables all the point images in the cylindrical space to be reconstructed, or the hologram array plate 10
Is rotated by a minute angle during one rotation, and if this is repeated for one rotation, any one of the driving methods of the above-described method in which all the point images in the cylindrical space can be reproduced can be adopted.

In any case, image rotator 2
The drive of No. 5 is performed in synchronization with the drive of the hologram array plate 10 or a beam conversion means equivalent thereto. In this method, the image reproducing optical system and the hologram are rotationally symmetric.

The present apparatus can be configured by replacing the beam converting section 53 with a spatial light modulator (SLM) that can generate and control hologram interference fringes electrically. FIG. 32 shows an example in which a spatial light modulator (SLM) is used as a beam converter. A block diagram of the present apparatus in such a configuration is different from that shown in FIG. 5 and is as shown in FIG.

In FIGS. 32 and 33, the stereoscopic image information control unit 51 switches the position information of the point image to be reproduced to the selection by itself, and transmits the luminance information signal to the pulse beam forming unit 52 according to the information. A hologram interference fringe information signal is sent to 53. The pulse beam forming unit 52 controls the beam generation as described above, and the beam converting unit 53 generates hologram interference fringes on the SLM according to the information signal. The pulse beam incident on the SLM is subjected to wavefront conversion by the hologram interference fringes, and after multiple reflection in the side reflection conical tube 5, forms a desired point image. Information on the hologram interference fringes to be generated on the SLM can be calculated in advance from position information on a point image to be reproduced and information on an illumination pulse beam. When the position of the point image to be reproduced is switched, the hologram interference fringes on the SLM are controlled to be switched, and this is performed at high speed, and finally, a desired three-dimensional image can be obtained as a set of point images.

[0079]

As described above, according to the present invention, when image information is recorded on a recording material and when image information recorded on the recording material is reproduced, an appropriately set waveguide type optical system is used. By using the same, it is possible to achieve an image recording apparatus and an image reproducing apparatus capable of observing a high-quality stereoscopic image (three-dimensional image) in a wide observation area even with a recording material having a relatively small area.

In particular, according to the present invention, hologram recording and
Reproduction is performed in a state where a waveguide type optical system and other optical systems are combined, and the size of the hologram can be suppressed smaller than the size of the reproducible image, and the hologram uses the waveguide type optical system It is possible to reproduce an arbitrary three-dimensional image by switching and reproducing them, and to record and reproduce holograms by using a waveguide type optical system while performing multiple multiplex reflection. It is possible to achieve an image recording apparatus and an image reproducing apparatus that can obtain effects such as efficient use of light by guiding the light in a predetermined direction.

[Brief description of the drawings]

FIG. 1 is a schematic view of a main part of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of recording and reproduction of a hologram.

FIG. 3 is an explanatory diagram of a hologram observation range.

FIG. 4 is an explanatory view of a part of FIG. 1;

FIG. 5 is a main part block diagram of the first embodiment of the present invention.

FIG. 6 is an explanatory view of a part of FIG. 1;

FIG. 7 is an explanatory view of a part of FIG. 1;

FIG. 8 is a schematic diagram of a main part of the image reproducing apparatus according to the first embodiment of the present invention.

FIG. 9 is an explanatory diagram of another embodiment of a part of the first embodiment of the present invention.

FIG. 10 is an explanatory diagram of another embodiment of a part of the first embodiment of the present invention.

FIG. 11 is an explanatory view of another embodiment of a part of the first embodiment of the present invention.

FIG. 12 is a diagram illustrating another embodiment of a part of the first embodiment of the present invention.

FIG. 13 is an explanatory diagram of another embodiment of a part of the first embodiment of the present invention.

FIG. 14 is an explanatory view of a waveguide type optical system according to the present invention.

FIG. 15 is an explanatory diagram of a waveguide type optical system according to the present invention.

FIG. 16 is an explanatory view of a waveguide type optical system according to the present invention.

FIG. 17 is an explanatory view of a waveguide type optical system according to the present invention.

FIG. 18 is an explanatory view of a waveguide type optical system according to the present invention.

FIG. 19 is an explanatory view of an optical trap.

FIG. 20 is a main part schematic diagram when a part of the first embodiment of the present invention is changed.

FIG. 21 is an explanatory view of a waveguide type optical system according to the present invention.

FIG. 22 is an explanatory view of a waveguide type optical system according to the present invention.

FIG. 23 is a schematic view of a main part of a second embodiment of the present invention.

FIG. 24 is an explanatory view of a part of FIG. 23;

FIG. 25 is a main part schematic diagram when a part of the second embodiment of the present invention is changed.

FIG. 26 is a schematic view of a main part when a part of the second embodiment of the present invention is changed.

FIG. 27 is a schematic view of a main part of a third embodiment of the present invention.

FIG. 28 is an explanatory view of a part of FIG. 27;

FIG. 29 is a main part schematic diagram when a part of the third embodiment of the present invention is changed.

FIG. 30 is a main part schematic diagram when a part of the third embodiment of the present invention is changed.

FIG. 31 is a schematic view of a main part when a part of the third embodiment of the present invention is changed.

FIG. 32 is a schematic view of a main part of a fourth embodiment of the present invention.

FIG. 33 is a main part block diagram of a fourth embodiment of the present invention.

FIG. 34 is a schematic view of a main part of a conventional hologram reproducing apparatus.

FIG. 35 is a schematic view of a main part of a conventional three-dimensional moving image display device.

FIG. 36 is an explanatory view of a part of FIG. 33. 1 Recording material 2 Hologram 3 Waveguide optical system 4 Wavefront 5 Side reflection cone tube 6 Computer 7 Light source 8 Light beam transmittance control unit 9 Hologram array plate displacement means 10 Hologram array Plate 14,17 cone 15 point light source 16 optical axis H hologram

Claims (9)

[Claims] 1. An object light based on an object light generating means for generating a coherent object light, the object light passing through a waveguide type optical system having an inner peripheral surface having a smaller exit aperture than an entrance aperture as a reflection surface. Forming interference information between the reference light from the reference light generating means and a reference light on a recording material surface, and recording image information based on the object light from the object light generating means on the recording material. Recording device. 2. The image recording apparatus according to claim 1, wherein said waveguide type optical system has a conical tube, a trumpet tube, or a horn tube. 3. An image recording apparatus according to claim 1, wherein said waveguide type optical system has a lens group. 4. The image recording apparatus according to claim 1, wherein said image information is three-dimensional image information. 5. A recording material on which image information is recorded using interference between object light and reference light is irradiated with illumination light having the same wavelength and the same wavefront as that of the reference light from an illuminating means, and is generated from the recording material. The reproduced light is guided to a waveguide type optical system having an inner peripheral surface having a larger exit aperture than the entrance aperture as a reflection surface, and the image information is reproduced from a light beam passing through the waveguide type optical system. An image reproducing apparatus, comprising: 6. A method in which a plurality of recording materials are provided on a drivable substrate, and the driving means drives the substrate so that at least one of the plurality of recording materials emits illumination light from the illumination means. 6. The image reproducing apparatus according to claim 5, wherein the light is irradiated. 7. The image reproducing apparatus according to claim 6, wherein the intensity of illumination light emitted from said illumination means is modulated by a control means based on the displacement information of said substrate. 8. The apparatus according to claim 5, wherein said image information is three-dimensional image information. 9. A recording material on which image information is recorded by using the image recording apparatus according to claim 1 is used for the image reproducing apparatus according to claim 5. An image recording and reproducing apparatus for reproducing image information recorded on a recording material.