JP2000029374A - Production of hologram - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a hologram which can display uniformly bright image and enables observing image having unchangeable brightness and color from a wide angle. SOLUTION: In a hologram manufacturing optical system 1 in which a photosensitive member 30 is converted to the hologram by interference between a reference ray 16 and an object ray 14 transmitted through a light diffuser 20, the light diffuser 20 is provided with a mirror 21 arranged in a direction approximately vertical thereto and further the photosensitive member 30 and the light diffuser 20 are arranged by rotating by the same angle θ with an axis vertically crossing the center of the photosensitive member 30 as a rotation center. In this manufacturing method of the hologram, P polarized light or S polarized light is attained by inclining the polarization direction of the laser beam to be used at θ-5 deg. to θ+5 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a hologram, which can be used as a display device for displaying images such as still images and moving images by irradiating image light.

[0002]

2. Description of the Related Art An object beam 14 and a reference beam 16 are made incident on a photosensitive member 30 using a hologram producing optical system 9 as shown in FIG. As a result, interference fringes formed by the object light 14 and the reference light 16 are recorded on the photosensitive member 30. Therefore, the light diffuser 20 is recorded on the photosensitive member 30, and the photosensitive member 30 becomes a hologram.

A hologram screen composed of such a hologram is used as a display device 35 for displaying images such as still images and moving images by irradiating image light 390 from an irradiation device 39 as shown in FIG. it can.

[0004]

By the way, a large screen may be required as a screen used for advertising exhibition products in a showroom. However, in the manufacturing method using the hologram manufacturing optical system 9 described above, it is very difficult to manufacture a large hologram by one photographing.

In other words, a large hologram requires a large photosensitive member, but the exposure of such a photosensitive member requires a long time. In addition, since it is necessary to irradiate the entire large photosensitive member with the reference light, the intensity of the reference light is weakened, and in this respect, there is a problem that the exposure time becomes long. For this reason, the exposure time may exceed the time during which the interference fringes can be stably stopped on the photosensitive member, and the production yield of the hologram may be deteriorated.

Further, in order to obtain object light capable of irradiating the entirety of a large photosensitive member, it is necessary to use a large light diffuser, but it is very difficult to manufacture such a light diffuser. Furthermore,
Since the object light obtained from such a large light diffuser is composed of diffused light diffused over a wide range, there is a problem that the intensity is low and the exposure time of the photosensitive member is long.

As means for solving this, the present applicants have proposed (1) a method of reducing the size of the photosensitive member and (2) a method of reducing the size of the light diffuser (Japanese Patent Application No. 9-349572).
issue). In the method (1), as shown in FIG.
It is conceivable to configure the hologram screen 3 by integrating a plurality of holograms 31 to 34 so as to have a two-dimensional spread via connection means. In this case, the four holograms 31 to 34 are separately manufactured and then connected.

In the method (2), FIG.
As shown in FIG. 3, it is conceivable to provide mirrors 21 to 24 perpendicular to the light diffuser 20. In this case, since the light diffuser 20 is reflected on the mirrors 21 to 24, it is possible to obtain wide and wide object light as in the case where the larger light diffuser 20 is arranged.

However, in the method (2), when combined with the method (1), sufficient recording is not performed on the photosensitive member from the light diffuser reflected on the mirror, and the light diffuser is directly There is a problem in that there is a difference in brightness between the portion recorded and recorded. As a result, there is a possibility that the image reflected on the hologram screen may be partially darkened or the color may change depending on the viewing angle of the observer. In some cases, the boundary line between the diffusion plate and the mirror is reflected on the hologram screen, which may cause an unsightly state.

The present invention has been made in view of such a conventional problem, and when used as a display device, it is possible to display a bright image uniformly, and to observe an image whose brightness and hue do not change from a wide angle. It is an object of the present invention to provide a method of manufacturing a hologram capable of performing the following.

[0011]

According to a first aspect of the present invention, there is provided a hologram producing optical system for recording a light diffuser on a photosensitive member to form a hologram by interference between reference light and object light transmitted through the light diffuser. The light diffuser is provided with a mirror arranged in a direction substantially perpendicular to the light diffuser, and the light diffusion member and the light diffusion member are rotated about an axis perpendicular to the center of the photosensitive member. A method for producing a hologram in a case where the hologram is arranged by rotating the body at the same angle θ,
A hologram manufacturing method according to the hologram manufacturing method, wherein the laser beam used in the hologram manufacturing method is P-polarized light or S-polarized light inclined at θ-5 to θ + 5 degrees.

The most remarkable point in the present invention is to use P-polarized light or S-polarized light having a polarization direction in the range of θ-5 degrees to θ + 5 degrees as the laser light. If the polarization direction is out of this range, the light diffuser reflected on the mirror will be dark, and the image may be partially dark depending on the viewing angle of the observer.

Next, the operation of the present invention will be described. The light diffuser used in the manufacturing method of the present invention is provided with a mirror perpendicular to the light diffuser (see FIGS. 2 and 3 described later). When the light diffuser is recorded on the photosensitive member, object light is emitted from the light diffuser, and a part of the object light directly reaches the photosensitive member. To arrive.

Accordingly, the angle range of incidence of the object light on the photosensitive member is widened, and a small light diffuser is used to obtain object light having the same spread as when a larger light diffuser is used. Can be.

When the hologram is manufactured, the light diffuser and the photosensitive member are rotated at the same angle θ about an axis perpendicular to the center point of the photosensitive member as the center of rotation. FIG. 8 illustrates the positional relationship among the photosensitive member 90, the light diffuser 94, and the reference beam 92, which is necessary for manufacturing a hologram screen 3 having the size shown in FIG.

In the same figure, when one large hologram screen 3 is formed by using four holograms 31 to 34 as shown in FIG. 5 described later, one hologram 31 is manufactured. The positional relationship between the photosensitive member 901 and the light diffuser 941 required for this is described.

In FIG. 8, the reference light 92 diverges on a plane AA formed by a center line X passing through the center point C of the photosensitive member 90 and an axis 905 which is perpendicularly incident on the center point C of the photosensitive member 90. There is a point 920. This divergence point 920
Means the objective lens 105 in the hologram producing optical system 9 described above.

Referring to FIG. 8, the photosensitive member 901
Through the center point C1 of the photosensitive member 901
Consider a straight line X1 that is parallel to a straight line X passing through. A plane including the straight line X1 and parallel to the plane AA is referred to as a plane AA1 (not shown). In this case, the divergence point 92 on the plane AA1
0 does not exist.

FIG. 9 is a view of FIG. 8 viewed from the z-axis direction.
It described in. As can be seen from the figure, the reference light 92 is directed toward the center point C1 of the photosensitive member 901 by the center line X (plane A).
It is necessary to irradiate obliquely at an angle of θb to A). When manufacturing the hologram 31 which constitutes a part of the large hologram screen 3 as described above, it is necessary to irradiate the reference beam 92 obliquely.

In FIG. 9, an axis passing through the center point C1 and perpendicular to the drawing is considered. The photosensitive member, the light diffuser 94, and the reference beam 92 are all rotated rightward by an angle θb shown in FIG. This state is shown in FIG.
0. As can be seen from the figure, the rotation of the angle θb causes the divergence point 920 of the reference light 92 to move on the plane AA1.

Therefore, when actually manufacturing a hologram, as described above, the light diffuser and the photosensitive member are set at the same angle θ.
Rotate with. Further, the reference light is incident on the photosensitive member on the same horizontal plane as the object light. If θ = θb, the hologram producing optical system for exposing the photosensitive member can be easily installed. Therefore, according to the present invention, the hologram can be easily and safely produced.

The cause of such a problem occurring in the prior art will be described in detail. In the present invention, as shown in FIG.
P-polarized or S-polarized light having a polarization direction in the range of degrees is used. Here, FIG. 4 illustrates a state where FIG. 3 is viewed from the direction a. It is assumed that the light diffuser is irradiated with S-polarized laser light having a polarization direction as indicated by an arrow L0 shown in FIG. The polarization direction is clear from the figure, but is perpendicular to the mirrors 24 and 23.

Here, when the light diffuser 20 and the mirrors 21 to 24 provided on the light diffuser 20 are rotated at an angle θ as shown in FIG. 12 about an axis perpendicular to the center point of the light diffuser 20 as a rotation center. think of. In this case, since the polarization direction of the laser light is the arrow L0 without change, it remains in the vertical direction (S-polarized light).

Considering the case where such a laser beam passes through the light diffuser 20 as shown in FIG. 13 and is reflected by the mirror 22 and the object beam Ob is formed by the reflection, the polarization direction of the object beam Ob is considered. Is considered. As shown in the figure, the polarization direction of the object light Oa that passes through the light diffuser 24 and reaches the mirror 22 is indicated by an arrow La. However, since the mirror 22 is inclined by the angle θ degrees, the polarization direction of the object light Ob reflected by the mirror 22 becomes the arrow Lb.
That is, it is inclined by an angle of 2θ degrees with respect to the polarization direction before being reflected.

The polarization direction of the reference light reaching the photosensitive member is the same as the polarization direction of the original laser light,
Polarization. Therefore, of the reflected object light Ob, the one that can contribute to the formation of interference fringes with the reference light is, as shown in FIG. 14, in the same direction as the arrow Lc indicating the vertical component of the arrow Lb. Only ingredients. In other words, the substantial intensity of the object light reflected by the mirror is attenuated, becomes weaker than the intensity of the object light directly incident on the photosensitive member after passing through the light diffuser, and the efficiency of interference fringes is directly applied to the photosensitive member. The efficiency becomes lower than the efficiency of interference fringes formed from the incident object light.

In this case, as described in the prior art, sufficient recording is not performed on the photosensitive member from the light diffuser reflected on the mirror, and the light diffuser is directly reflected and recorded between the recorded portion and the photosensitive member. , A difference occurs in brightness. As a result, there is a possibility that a problem that the image reflected on the hologram screen is partially darkened depending on the viewing angle of the observer.

As described above, the present invention uses P-polarized light or S-polarized light having a polarization direction in the range of θ-5 degrees to θ + 5 degrees as laser light. Therefore, even a light diffuser or a mirror inclined at an angle θ can be in a state of P-polarized light or S-polarized light.

That is, in the present invention, since the object light is prevented from being reflected by the mirror and the polarization direction is largely changed, the above-mentioned problem can be prevented, and the hologram can be partially darkened. The image can be prevented from being partially darkened depending on the viewing angle of the observer. Note that, for example, in FIG. 4, the laser polarization direction is inclined by θ degrees so that the polarization direction of the laser light is parallel to the mirrors 21 and 22 in FIG. The polarization direction perpendicular to this (parallel to the mirrors 23 and 24) is called P-polarized light having an angle θ.

As described above, according to the present invention, a method for manufacturing a large hologram which can display a uniformly bright image, can be observed from a wide angle, can be manufactured safely, and has excellent manufacturing yield. Can be provided.

The laser light used in the manufacturing method of the present invention is generated by using a general laser oscillator. By providing a half-wave plate to the laser oscillator, the above-mentioned θ-5 degrees or less can be obtained. P-polarized light or S-polarized light having a polarization direction in the range of θ + 5 degrees can be generated.

Here, the wave plate is an optical element that changes the polarization state of the light wave by giving a phase difference to the light wave due to the difference in the refractive index of the optical crystal having the optical anisotropy with respect to the polarization component. The half-wave plate is an optical element that can change the polarization direction of linearly polarized light. When linearly polarized light is incident on the optical axis of the half-wave plate at an angle of θ, the polarization direction of the outgoing light is inclined by 2θ with respect to the incident light. The above θ can be changed continuously. As described above, by using the half-wave plate, a laser beam having a desired polarization direction can be easily obtained.

As the half-wave plate, a wave plate that achieves the above function by utilizing the optical anisotropy of the optical crystal can be used. Further, as the half-wave plate, a Fresnel rhomb wave plate using total reflection in the optical element can be used. In particular, a Fresnel rhomb wave plate can be used for high-power laser light, and has a wide range of wavelengths of laser light that can be used. In this regard, it is particularly preferable to use a Fresnel rhomb wave plate as the half wave plate.

As a method of integrating the plurality of holograms, for example, the hologram may be attached to a film with an adhesive (for example, a PTE film), or attached to a large glass using a colorless and transparent optical adhesive. Method. As the laser light, for example, light oscillated by an Ar laser oscillator can be used. As the photosensitive member, for example, a photopolymer, gelatin dichromate, or the like can be used. As the light diffuser, for example, frosted glass or opal glass can be used.

According to the manufacturing method of the present invention,
A transparent hologram constituting the hologram screen can be manufactured. In this case, a transparent hologram screen can be obtained by making the joining means of the hologram transparent. This makes it possible to display advertisements on show windows in department stores and underground shopping malls, and to serve customers at the same time while displaying necessary information at the counters of banks and hospitals. Can be obtained.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 A method for manufacturing a hologram according to an embodiment of the present invention, a hologram manufacturing optical system used for the manufacturing, and a hologram screen as a display device constituted by the obtained hologram are described. This will be described with reference to FIGS. In the present example, as shown in FIG.
A method of manufacturing the hologram screen 3 in which the hologram screen 4 is integrated so as to have a two-dimensional spread via the connection means will be described.

The outline of the manufacturing method of this embodiment will be described.
As shown in FIG. 1, a laser beam 11 is divided into
2 and 15 are formed, one of the separated lights 12 is transmitted through the light diffuser 20 to form the object light 14, and the other separated light 15 is formed as the reference light 16. The object light 14 and the reference light 16 are incident on the photosensitive member 30 on the same horizontal plane, and the light diffuser 20 is recorded on the photosensitive member 30 to manufacture each of the holograms 31 to 34. Then, this hologram 3
1 to 34 are integrated into one large hologram screen 3 as shown in FIG.

In this manufacture, as shown in FIGS. 1 to 3, the light diffuser 20 is provided with mirrors 21 to 24 in a direction perpendicular to the light diffuser 20. As shown in FIG. 3, an axis 20 perpendicular to the center of the photosensitive member 30 is provided.
The light diffuser 20 and the mirrors 21 to 2 are rotated around 0 as a rotation center.
4 and the photosensitive member 30 are rotated at the same angle θ, and S-polarized light having a polarization direction of the angle θ is used as the laser light 11. This rotation angle θ is equal to the holograms 31 to 3
All four differ.

The details will be described below. As shown in FIG. 1, in the hologram producing optical system 1, a wave plate 101 is provided between a laser oscillator 10 and a beam splitter 102, and a laser beam passes through the wave plate 101 to make a polarization of θ degrees. It becomes S polarized light having a direction. The wave plate 101 is a Fresnel rhomb 1/2 wave plate. The laser oscillator 10 is an Ar laser oscillator. The laser light oscillated by the laser oscillator 10 and passed through the wave plate 101 is split into two beams by the beam splitter 102, and the separated light 1
2,15.

After one split light 12 is converted into divergent light 130 by the objective lens 103, it is converted into parallel light 13 by the off-axis parabolic mirror 104. After that, the parallel light 13 passes through the light diffusion section 2 to form diffused light. This diffused light becomes the object light 14. Further, the other separated light 15 is passed through the objective lens 105 and becomes the reference light 16.

As shown in FIGS. 2 and 3, the light diffusing section 2 is a rectangular and plate-shaped light diffusing body 2 made of frosted glass.
0 and a mirror 2 disposed perpendicular to the light diffuser 20
1 to 24. In the light diffusing unit 2, the length of the mirror 21 is shorter than that of the other mirrors 22 to 24, in order to form a space into which the reference light 16 is introduced. Each of the mirrors 21 to 24 is a mirror made of a dielectric multilayer film and the phase of reflected light is not shifted. This mirror may be a mirror made of a metal deposition film. However,
The mirror faces inwards.

As shown in FIG. 4, the light diffusing section 2 is disposed in a state of being rotated by an angle θ degrees to the right with respect to the axis 200 in the drawing. Since the light diffuser 2 is disposed perpendicular to the light diffuser 20, the light diffuser 20 is disposed in a state where the light diffuser 20 is rotated at an angle θ degrees. Further, although not shown, the photosensitive member 30 is also rotated and disposed at the same angle. The polarization direction of the parallel light 13 entering the light diffuser 20 is the direction of the arrow L as shown in FIG. That is,
This polarization direction is also θ degrees.

Then, the object light 14 and the reference light 16
Are incident on the photosensitive member 30, and the interference fringes formed by the two are recorded on the photosensitive member 30. As a result, the light diffuser 20 is recorded on the photosensitive member 30, and becomes a hologram functioning as a screen as described later. Holograms 31 to 34 having a diagonal length of 20 inches are prepared by the above-described manufacturing method.

However, the rotation angle θ is different for all four sheets.
For example, in FIG. 5, when the image light 390 is incident on the center of 40 inches at an angle of 35 degrees, the hologram 31 is 15 degrees to the right, the hologram 32 is 15 degrees to the left, the hologram 33 is 11 degrees to the left, and the hologram 34 Is 11 degrees to the right.

Next, a method of connecting the holograms 31 to 34 will be described. As shown in FIG. 7A, a hologram 31 is laminated on a glass substrate 41, and a transparent PET with an adhesive layer is formed on the glass substrate 41 using a roller 40.
A film 42 (20 inch size) is attached. Next, the hologram 31 and the transparent PET film
After cutting the portion exceeding the inch size, the glass substrate 4
Remove 1

Thereafter, the other holograms 32, 33, 34
, A transparent PET film 42 is also attached. Then, as shown in FIG. 7B, the holograms 31 to 34 are arranged so that there is no gap, with the surface where the hologram is exposed facing up, and then a transparent P with an adhesive layer of 40 inches in size.
The ET film 43 was stuck by the roller 40. As described above, one large hologram screen 3 having a diagonal length of 40 inches is obtained.

Next, a display device 35 using the hologram screen 3 according to this embodiment will be described. As shown in FIG. 6, an image projection device 39 such as a projector is arranged above the back side of the hologram screen 3. The image projected by the projection light from the image projection device 39 is formed on the hologram screen 3 so that the observer 38
Can observe an image on the hologram screen 3.

That is, when the projection light is applied,
The light diffuser 20 recorded on the holograms 31 to 34 is reproduced, and the holograms 31 to 34 diffract and diffuse the image light in the same manner as when the diffused light is emitted from the light diffuser 20.
Thereby, the holograms 31 to 34 function as a screen. Since the holograms 31 to 34 are transparent and the connection means of the holograms 31 to 34 are transparent PET films 42 and 43, the observer 38 can observe the background 381 together with the video.

The operation and effect of this embodiment will be described. The light diffuser used in the manufacturing method of this example is provided with a mirror perpendicular to the light diffuser (see FIGS. 2 and 3). In the exposure of the photosensitive member, object light is emitted from the light diffuser by making the separated light incident on the light diffuser, and a part of the object light directly reaches the photosensitive member, but the rest of the object light is reflected by the mirror. After being reflected once, it reaches the photosensitive member.

Therefore, the angle range of incidence of the object light on the photosensitive member is widened, and the object light having the same spread as that obtained by using the larger light diffuser can be obtained by using a small light diffuser. Can be.

In this embodiment, four holograms are individually manufactured, and these are integrated to manufacture a hologram screen. When manufacturing this hologram, the light diffuser and the photosensitive member are rotated at the same angle θ as described above.
Is different for each of the four holograms. Further, the reference light is incident on the photosensitive member on the same horizontal plane as the object light.

In this embodiment, as described above, S-polarized light having a polarization direction of θ degrees is used as laser light. Accordingly, as described above, the polarization direction of the object light can be set to the S-polarized state even with respect to the light diffuser or the mirror inclined at the angle θ. That is, in this example, since the object light is prevented from being reflected by the mirror and the polarization direction is largely changed, the above-described problem can be prevented, and the hologram can be partially darkened or the observer's view can be reduced. It is possible to prevent the image from being partially darkened depending on the viewing angle.

As described above, according to the present embodiment, it is possible to provide a method of manufacturing a hologram capable of displaying a uniformly bright image and observing an image whose brightness and color are unchanged from a wide angle.

Embodiment 2 As shown in FIGS. 15 to 22, this embodiment is directed to a manufacturing method according to the present invention shown in Embodiment 1 (with an angle of 1 as laser light).
The comparison is made between a manufacturing method using S-polarized light having a polarization direction of 5 °) and a manufacturing method using S-polarized light having a polarization direction of 0 ° as laser light. First, the hologram screens 3 manufactured by both manufacturing methods were prepared. For this hologram screen 3, as shown in FIG.
A white screen is projected from above by using the video projection device 39,
An observer 38 visually observed the hologram screen 3 at an angle of 15 degrees.

According to this observation, it was found that the hologram screen 3 obtained by the manufacturing method according to the present invention was uniformly whitish as a whole, but the S-polarized light having no polarization direction at an angle of 15 degrees as a laser beam. As shown in FIG. 16, in the hologram screen according to the manufacturing method (hereinafter, comparative example) using, a dark m part was observed in addition to a bright n part. A boundary line was clearly shown between the m and n portions, and this boundary line was located at a height of 60 mm from the lower edge of the hologram screen. It is considered that the m portion is a portion where the light diffuser is recorded by the object light reflected by the mirror. This hologram corresponds to hologram 34 in FIG.

In order to examine this point in more detail, a color luminance meter is installed at the position of the eyes of the observer 38 as shown in FIG. 15, and the luminance and chromaticity (u ′) of the six measurement points shown in FIG. , V ') [CIE1976 UCS chromaticity coordinates (u', v '), described in JIS standard Z8729]. The measurement results are shown in FIGS.
Note that the "position" on the horizontal axis in FIGS.
As shown in FIG. 5, it is the height from the lower end of the hologram screen 3. These measurement points are located 200 mm from the right end of the hologram screen 3.

As can be seen from the measurement results shown in FIGS. 17 to 22, in the hologram screen 3 according to the manufacturing method according to the present invention, the boundary between the mirror side and the light diffuser side is not clear, and the difference in luminance and chromaticity is almost zero. I knew it wasn't. on the other hand,
In the comparative example, both the luminance and the chromaticity varied discontinuously at the above boundary, and it was found that the portion exposed by the mirror-side object light was dark and had a different color. As described above, according to the manufacturing method of the present invention, it was found that a hologram screen capable of displaying a uniformly bright image can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a hologram producing optical system used for producing a hologram constituting a hologram screen in a first embodiment.

FIG. 2 is an explanatory perspective view of a light diffusing body according to the first embodiment.

FIG. 3 is an explanatory view of a main part of a light diffuser in the first embodiment.

FIG. 4 is a plan view of a light diffuser section according to the first embodiment.

FIG. 5 is an explanatory diagram of a hologram screen in the first embodiment.

FIG. 6 is an explanatory diagram of a display device using a hologram screen in the first embodiment.

FIG. 7 is an explanatory view showing a hologram connection method in the first embodiment.

FIG. 8 is an explanatory diagram showing a positional relationship between a light diffuser and reference light when exposing photosensitive members 90 and 901.

9 is a plan view of the photosensitive member 901, the light diffuser, and the reference light as viewed from the z-axis direction in FIG.

FIG. 10 is a plan view showing a state where the photosensitive member 901, the light diffuser, and the reference light according to FIG. 9 are rotated.

FIG. 11 is a plan view showing a relationship between a light diffusion unit and a polarization direction.

FIG. 12 is a plan view showing a state where the light diffusion unit according to FIG. 11 is rotated.

FIG. 13 is an explanatory diagram showing the polarization directions of object light Oa formed by passing through a light diffusion unit and object light Ob reflected by the mirror.

FIG. 14 is an explanatory diagram showing a relationship between the object light Ob according to FIG. 13 and reference light in the hologram producing optical system.

FIG. 15 is an explanatory diagram of a hologram screen observation method according to the second embodiment.

FIG. 16 is an explanatory diagram of a hologram screen measuring method according to the second embodiment.

FIG. 17 is an explanatory diagram showing the relationship between the position of the measurement point and the luminance on the hologram screen according to Embodiment 2 by the manufacturing method of the present invention.

FIG. 18 shows the position of a measurement point and u ′ on a hologram screen according to Embodiment 2 of the present invention, which is manufactured by the manufacturing method.
FIG.

FIG. 19 is a diagram illustrating a position of a measurement point and v ′ on a hologram screen according to a second embodiment of the present invention, which are manufactured by the manufacturing method.
FIG.

FIG. 20 is an explanatory diagram showing the relationship between the position of the measurement point and the luminance on the hologram screen according to the manufacturing method of the comparative example according to the second embodiment.

FIG. 21 shows the positions of measurement points and u ′ on the hologram screen according to the manufacturing method of the comparative example according to the second embodiment.
FIG.

FIG. 22 shows the position of a measurement point and v ′ on the hologram screen according to the manufacturing method of the comparative example according to the second embodiment.
FIG.

FIG. 23 is an explanatory diagram of a hologram producing optical system that can be used for producing a conventional hologram screen.

[Explanation of symbols]

 1. . . Hologram production optical system, 12,15. . . Separated light, 14. . . Object light, 16. . . Reference light, 20. . . Light diffuser, 21-24. . . Mirror, 3. . . Hologram screen, 30. . . Photosensitive member, 31-34. . . hologram,

Claims (1)

[Claims] In a hologram producing optical system for recording a light diffuser on a photosensitive member to form a hologram by interference between reference light and object light transmitted through the light diffuser, the light diffuser includes a light diffuser. A mirror disposed substantially perpendicular to the body, and rotating the photosensitive member and the light diffuser at the same angle θ about an axis perpendicular to the center of the photosensitive member as a rotation center; A method of manufacturing a hologram when arranged, wherein the polarization direction of a laser beam used in the method of manufacturing a hologram is P-polarized light or S-polarized light inclined at θ-5 to θ + 5 degrees. Method.