JP2003015229A - Hologram screen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hologram screen superior in color reproducibility. SOLUTION: The screen is constituted of a hologram element 11 having a function for diffracting projected light 21 projected from a projector 2 and a light scattering element which is combined with the hologram element 11 and scatters projected light 21 made incident in the range of a specified incident angle. It is desirable that the range of the specified incident angel is 25 to 60 deg. and the scattering degree of the light scattering element 12 is not less than 5 deg.. The light scattering element 12 is arranged on a projector side, or the light scattering element 12 is arranged on the opposite side of the projector side.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a transmissive hologram screen that uses a hologram element as a screen.

[0002]

2. Description of the Related Art FIG. 17 shows a transparent hologram screen which is attached to a show window or the like and used as a display for displaying advertisements or the like in moving images or still images. As shown in FIG. 17, the hologram screen 9 is used by the observer 6
With respect to the hologram element 11, projection light 21 is projected on the hologram element 11 from a projection device 2 (for example, a projector) provided below (or above) the hologram element 11 to form an image, and the projection is performed by the hologram element 11. Light 21
The image was made to be recognized by the observer 6 by diffracting / scattering to the front.

The hologram element 11 used in such a transmissive hologram screen 9 is manufactured by recording the diffuser 88 on the photosensitive member 85 by the exposure optical system 8 as shown in FIG.

A laser beam 800 (for example, a wavelength of 514.5 nm) emitted from a laser oscillator 80 (for example, an Ar laser) is split into two directions by a semitransparent mirror 890. One of the lights passes through two reflecting mirrors 891 and becomes divergent light by the objective lens 831 and then is projected onto the photosensitive member 85. Note that this light is the reference light 86. Further, the other light also passes through the two reflecting mirrors 892, becomes divergent light by the objective lens 832, and then is introduced into the parabolic mirror 89. The light reflected by the parabolic mirror 89 passes through the diffuser 88 to be diffused light, and then is projected on the photosensitive member 85. The light from the diffuser 88 becomes the object light 87.

[0005]

However, in the hologram screen 9 using the hologram element 11 manufactured in this way, the image projected from the projection device 2 has a greenish color tone, and the color of the projected image varies. There was a problem that it was not reproduced sufficiently.

By the way, the spectral characteristic of the hologram element 11 is measured by a method as shown in FIG. In this measuring method, white light 901 is made incident on the hologram element 11 at an angle equal to the incident angle θr of the reference light 86 of the exposure optical system 8 shown in FIG. In particular, the wavelength of the diffracted light 902 emitted in the 0 ° direction and the efficiency (= the intensity of the diffracted light in the direction of 100 × 0 ° / the intensity of white light [%]) are measured. The 0 ° direction is a direction perpendicular to the surface of the hologram element 11.

From these measurement results, spectral characteristics having a distribution as shown in the diagram of FIG. 20 were obtained. According to the figure, it was found that this characteristic has a peak in the blue to green wavelength range and the wavelength in the red range is weak. That is, since the hologram element 11 has a spectral characteristic having a distribution in which the efficiency greatly differs depending on the wavelength, it is considered that the color reproducibility of the image is deteriorated.

In view of the above problems, the present invention aims to provide a hologram screen having excellent color reproducibility.

[0009]

According to a first aspect of the present invention, a hologram element having a function of diffracting projection light projected by a projection device is combined with the hologram element, and the hologram element is incident within a specific incident angle range. A hologram screen characterized by comprising a light scattering element for scattering projection light.

As a result, the background light of the hologram screen can be transmitted and only the projection light from the projection device can be scattered. Therefore, the color reproducibility can be enhanced without impairing the transparency of the hologram screen.

The range of the specific incident angle cannot be unconditionally specified because it is determined by the size of the hologram screen and the positional relationship between the projection device and the like. That is, as shown in FIG. 5 described later, the incident angle to the center is m ° in the hologram screen, but is 1 or n ° at the end of the hologram screen. In this case, a light scattering element capable of scattering the incident light in the range of 1 to n is preferable.

[0012]

Further, it is preferable that the specific incident angle range is 25 to 60 °. In many cases, the angle when the projection light from the projection device is incident on the central portion of the hologram screen is generally around 35 °. In such a case, about 25-60 °
It is preferable to use a light scattering element that can scatter light in the range of the incident angle.

The light scattering element preferably has a scattering degree of 5 ° or more (claim 3). By using a light scattering element having a scattering degree of 5 ° or more, the effect of the present invention can be reliably obtained, as is known from FIG. 14 of Example 2 described later. If the scattering degree is less than 5 °, it may be difficult to obtain the effects of the present invention. Moreover, it is preferable that the upper limit of the above-mentioned scattering degree is defined by claim 6 described later. If the degree of scattering is larger than this, the projected components may be scattered too much to darken the image or impair the transparency of the hologram screen. The definition of scattering degree is described in Example 2 described later.

The hologram screen according to the invention of claim 3 is a combination of a hologram element and a light scattering element. Here, the effect of the light scattering element will be described. To clarify the effect of the light scattering element, the principle of the transmission hologram screen will be described first.

The exposure optical system 8 as shown in FIG.
Interference fringes having various inclinations are recorded on the hologram element in which the diffuser 88 is recorded. That is, in every part of the hologram element
Interference fringes of different types of inclination are not recorded, but interference fringes of multiple types of inclination are recorded in multiple places at one location.

The state of such a hologram element is schematically shown in FIG. However, in FIG. 8, for the sake of clarity, three interference fringes are shown for each of the three types of interference fringes, and one of the interference fringes is particularly indicated by a thick line. More interference fringes are recorded in the actual hologram element.

The inclination of the interference fringes is as shown in FIG.
An arbitrary point 850 on the photosensitive member 85 in the exposure optical system 8
At, the object light 870 that interferes with the reference light 860 is determined by the position on the diffusion plate 88 from which the object light 870 enters. For example, the interference fringe a in FIG. 8 is formed by the object light 8-a in FIG. 9 and the reference light 860 interfering with each other.
Interference fringe b or c of the object light 8-b or 8 of FIG.
-C and the reference light 860 are formed by interference.

White light 2 is generated on such interference fringes a or b.
FIG. 10 shows a state of the diffracted light 290 when 9 is incident on the exposure optical system 8 at the same angle θr as the reference light 86. 10A illustrates the case where the white light 29 is incident on the interference fringe a, and FIG. 10B illustrates the case where the white light 29 is incident on the interference fringe b.

When white light 29 is incident on the interference fringe a, light having the same wavelength as the recording wavelength is diffracted in the direction of arrow y. The direction of this arrow line y is the same direction as the object light 8-a shown in FIG. The diffracted light 290 obtained from the white light 29 is a component other than the diffracted light diffracted in the arrow direction y, a component having a wavelength longer than the recording wavelength, and a component diffracted in the direction of the arrow x And is composed of components diffracted in the direction of the arrow z.

That is, the white light 29 becomes the diffracted light 290 color-separated into the elliptical range shown in FIG. 10A, and is diffracted and scattered forward from the hologram element. Then, of the diffracted light 290, only the component of the diffracted light diffracted in the direction of the arrow v, which is the 0 ° direction, is detected in the above-described measurement of the spectral characteristics.

Further, FIG. 10B shows the case where the white light 29 is incident on the interference fringe b. In this case, the white light 29 is diffracted / scattered while being color-separated into the elliptical range shown in the figure, and among the diffracted light, the light having the same wavelength as the recording wavelength is diffracted in the direction of the arrow y. . In this case, since the direction of the arrow line y is equal to the 0 ° direction, what is detected in the measurement of the spectral characteristics is the light diffracted in the arrow line y direction. In this way, the wavelength of the light diffracted in the 0 ° direction varies depending on the inclination of the interference fringes.

As described above, diffracted light having various wavelengths and directions is formed by all the interference fringes recorded on an arbitrary portion of the hologram element. Then, the total sum of the diffracted light in the 0 ° direction formed by all the interference fringes is detected in the spectral characteristic, and the diagram of the spectral characteristic having the peaks in the blue and green regions as shown in FIG. 20 is formed. Of. Then, this spectral characteristic reflects the state of light from the hologram screen entering the eyes of the observer in front of the screen (that is, even in the observer, the diffracted light from the hologram screen has a blue or green tone). Observed).

Here, referring to FIG. 11, when the white light 28 is incident on the interference fringe b shown in FIG. 10B at an angle g larger than the incident angle θr of the reference light 86 incident on the exposure optical system 8. The state of the diffracted light 290 will be described.

As can be seen from the Bragg diffraction formula, in such a case, light having the same wavelength as the recording wavelength is diffracted in the arrow z direction, and light having a wavelength longer than the recording wavelength is indicated by the arrow x.
Will be diffracted in the direction of, that is, in the 0 ° direction. vice versa,
When white light is incident at an angle smaller than the incident angle θr, light having a wavelength shorter than the recording wavelength is diffracted in the 0 ° direction.

Therefore, for interference fringes having a certain inclination,
When white light having a certain range of incident angles is incident, the diffracted light diffracted in the 0 ° direction by this interference fringe has a wider wavelength distribution. Therefore, the spectral characteristics of the diffracted light can be broad with little difference in efficiency depending on the wavelength. That is, by making the incident angle of the projection light on the hologram element have a certain width, the diffracted light from the hologram element is in a state close to white, which is closer to the light source color.

The present invention has been devised based on the above consideration, and has a certain width in the incident angle of the projection light (corresponding to the white light in the above description) from the projection device with respect to the hologram element. The light scattering element is combined with the hologram element. By this,
The color reproducibility of projection light can be improved.

The above consideration has been mainly concerned with the projection light incident on the hologram element. On the contrary, by scattering the diffracted light emitted from the hologram element, the same effect as above can be obtained. in this case,
The diffracted light from the hologram element obtained by making white light incident has a peak in the blue or green wavelength region as described above. It can be a white state close to the color. As a result, the color reproducibility of the projected light can be improved.

As described above, according to the present invention, it is possible to provide a hologram screen having excellent color reproducibility.

The light scattering element can be arranged at a certain distance from the hologram element.
In other words, when an image is projected on the hologram element by scattering the projection light by the light scattering element, it is possible that the image is not overlapped with the image projected on the hologram element and does not appear double. It is necessary to keep a certain distance.

Further, when the distance between the light scattering element and the hologram element is large, the component of the projection light scattered at an angle such that the light cannot be incident on the hologram element increases, so that the utilization efficiency of the projection light is improved. It may deteriorate and the image may become dark (when a light scattering element is provided on the side where the projection light enters). Therefore, it is preferable that the light scattering element and the hologram element are arranged as close to each other as possible.

Further, it is preferable that the light scattering element is arranged on the projection device side (claim 4). Alternatively, it is preferable that the light scattering element is arranged on the side opposite to the projection device side (claim 5). In any case, the effects of the present invention can be obtained as described above. Also,
It is possible to obtain the effect of improving the glare due to the 0th-order light.

The vertical transmittance of the light scattering element is 30.
It is preferably in the range of -100% (claim 6). As a result, the light scattering element can transmit the background light of the hologram screen. Therefore, the observer can observe the object behind it through the hologram screen, and the application range of the hologram screen can be expanded (attached to a show window, etc., and used as a display for displaying advertisements such as moving images or still images). use).

Further, the above-mentioned light scattering element makes incident light at least sin ⁻¹ {sin θi−λ1 / λ0 · (sin θo −s
in θr)} ≦ θ ≦ sin ⁻¹ {sin θi−λ2 / λ0 · (sin θ
o −sin θr)} (where, λ0: hologram recording wavelength, λ1 = 380n
m, λ2 = 780 nm [visible light region is 380 to 780 n
m], θr: reference light incident angle, θo: object light incident angle, θ
i: angle θ determined by a mathematical formula for the diffracted light emission angle)
It is preferable to scatter within the range of.

As a result, the color of the projection light from the projection device can be reproduced almost completely. If θ is less than the lower limit of the above range, the color reproducibility may be felt to be poor. On the other hand, when θ exceeds the above range,
The image may become too dark or the transparency of the hologram screen may be impaired.

Incidentally, λ0 in the above formula is a recording wavelength when the hologram element is manufactured. That is, when the laser light 800 in the exposure optical system 8 according to FIG. 18 is an Ar laser, λ0 = 514.5 nm. Since λ1 and λ2 are wavelengths at both ends of the visible light region, they are 380 nm and 780 nm, respectively. As shown in FIG. 7A, θr is the incident angle of the reference beam 86 to the point 85 on the photosensitive member 85 in the exposure optical system 8, and θo is the object beam 87.
The incident angle of θi is θi, and the outgoing angle of the diffracted light 211 diffracted and scattered by the hologram element 11 is θi, as shown in FIG. 7B.

As a practical problem, the light-scattering element has a capability of scattering incident light at an angle obtained by assuming that the incident angle of the object light 87 is θo = 0 ° and the outgoing angle of the diffracted light 211 is θi = 0 °. If so, it is possible to obtain sufficient color reproducibility to the extent that there is no problem in observing the projected light with eyes.

[0037]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) A hologram screen according to an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the hologram screen 1 according to the present embodiment includes a projection device 2
A hologram element 11 having a function of diffracting the projected projection light 21 and a light scattering element 12 are combined, and the light scattering element 12 is arranged on the projection device 2 side via an adhesive layer 13. .

The light scattering element 12 has a function of sin ⁻¹ {sin θi−λ1 / λ0 · (sin θo −s
in θr)} ≦ θ ≦ sin ⁻¹ {sin θi−λ2 / λ0 · (sin θ
o −sin θr)} (where, λ0: hologram recording wavelength, λ1 = 380n
m, λ2 = 780 nm [visible light region is 380 to 780 n
m], θr: reference light incident angle, θo: object light incident angle, θ
i: angle θ determined by a mathematical formula for the diffracted light emission angle)
It has a function to scatter incident light within the range.

The details will be described below. The hologram element 11 according to this example is produced by the exposure optical system 8 according to FIG. In the exposure optical system 8, as shown in FIG. 7A, the incident angle θo of the object light is
The diffusing plate 88 is arranged so that the angle is −20 to 10 °. Further, as shown in FIG. 7A, the incident angle θr of the reference light 86 is 35 °.

As shown in FIGS. 5 and 6, the projection light 2
1 is scattered by the light scattering element 12 and becomes scattered projection light 210 and enters the hologram element 11. As shown in FIG. 7B, the scattered projection light 210 is diffracted and scattered by the hologram element 11 to become diffracted light 211. The emission angle θi of this diffracted light can be regarded as 0 ° because the observer observes the screen in front of the hologram screen.

Therefore, in the above equation, θr = 35
When θ, θo = 0 °, and θi = 0 ° were substituted, the range of θ was 25 to 60 °. As a light scattering element having such a scattering characteristic, in this example, a directional light scattering film (Lumisty-MFY-2 manufactured by Sumitomo Chemical Co., Ltd.) having an adhesive layer 13 is used.
555) was used.

The scattering characteristics of the above directional light-scattering film are shown in FIG. This scattering characteristic is obtained by measuring the intensity of scattered light β emitted from white light α at an angle of 35 ° with respect to the directional light scattering film in the measurement system as shown in FIG. As shown in FIG. 2, the directional light-scattering film used in this example transmits the light incident at an angle of about 20 ° or less, but scatters the light from the point of exceeding 20 °. it can. However, a realistic scattering power is obtained in the range of 25 to 60 °.

Therefore, by using this directional scattering film as the light scattering element 12 in the hologram screen 1, the background light of the hologram screen 1 passes through the screen and reaches the observer 6. The observer 6 can observe the background light and feels that the hologram screen 1 is transparent. The adhesive layer 13 is made of a highly transparent material and does not impair the transparency of the hologram screen.

Next, FIG. 4 shows the results of measurement of the spectral characteristics described in the above-mentioned prior art for the hologram screen 1 according to this example. For comparison, the spectral characteristics of the hologram element 11 alone are also described.

As can be seen from the figure, the spectral characteristics of the hologram screen 1 are broad with very little difference in efficiency depending on the wavelength, and even when observed with the naked eye, the hologram element 11 alone shows an image with a greenish color tone. It was confirmed that the color of the image on the projection device could be reproduced almost completely.

Next, the function and effect of this example will be described. FIG. 5 shows a hologram screen 1 according to this example in which the light scattering element 12 and the hologram element 11 are combined.
The projection light 21 from the projection device 2 becomes the scattered projection light 210 in the light scattering element 12, and enters the hologram element 11. As shown in FIG. 6, when viewed from the point A on the hologram element 11, scattered projection light 210 scattered at different positions on the light scattering element 12 enters from different angles like 3a, 3b, and 3c. .

By thus providing the light scattering element 12, the incident angle of the projection light 21 on the hologram element 11 has a certain range. Therefore, the spectral characteristic of the hologram element 11 can be broadened,
The color reproducibility of the hologram screen 1 can be improved.

The directional light-scattering film may be translucent when the hologram screen does not need to be completely transparent (for example, a colored screen). The same applies to the adhesive layer 13. Further, a hologram element having a light scattering action can be used as the light scattering element. For example, the same effect as that of the light-scattering element can be obtained by laminating one or a plurality of the same hologram elements as those used in this example in a laminated manner. Further, in the present example, the light scattering element 12 is provided on the projection device 2 side, but on the contrary, the light scattering element may be provided on the observer side.

(Example 2) In this example, a performance test relating to the scattering degree of the light scattering element will be described with reference to FIGS. Here, the optimum scattering degree of the light scattering element used in the present invention was obtained. The experimental results are shown below. In the experiment, one to five translucent films were laminated to form a laminate. As shown in FIG. 12, incident light 51 made of laser light having a wavelength of 514.5 nm was incident on each of the obtained laminated bodies 52 at an angle of 35 °. Each laminated body 52
The brightness of the outgoing light 53 that has been transmitted through and is measured while moving the luminance meter 5 in the angle θ direction.

Let K be the obtained luminance applied to each θ, and θ =
(K / K0) × 100, where K0 is the brightness at 0 °
The light receiving rate of [%] was calculated. A graph according to FIG. 13 was obtained with the obtained light receiving rate on the vertical axis and θ on the horizontal axis. In the figure, the range of θ when the light receiving rate is 50% or more is defined as the scattering degree. That is, for example, in one translucent film, the range in which the light receiving rate is 50% or more is 34 to
It is 36 °. In this case, the degree of scattering is 2 °. Others are the same.

A hologram screen having a structure according to Example 1 was produced using each of the above-described laminated bodies 52.
For comparison, a conventional hologram screen having the same structure and having no laminated body was also manufactured. We also prepared a normal opaque white screen that does not use a hologram element.

Then, the same projection light was projected from the same projector onto each hologram screen, conventional hologram screen, and opaque white screen, and a plurality of observers observed the hue of the image projected on each screen. . The results of this observation are shown in FIG. In the figure, "no change" means that the hologram screen is the same as the conventional hologram screen.
“Improved” means that the color tone is improved as compared with the conventional hologram screen.
“Very good” means that the image is close to the image on an opaque white screen.

As is known from the figure, it was found that most of the viewers perceived that the image reproduced on the hologram screen produced by the light scattering element having a scattering degree of 5 ° or more had improved color reproducibility. It was also found that the light scattering element can be used alone, but it is also possible to stack and use a plurality of sheets.

(Embodiment 3) In this embodiment, a hologram screen used by adhering to a window glass as shown in FIGS. 15 and 16 will be described. As shown in FIG. 15, the holographic screen 1 according to the present embodiment includes a hologram film 11 and a cover film 85 via an adhesive 13.
And the light scattering element 12 is attached with an adhesive 13, and the light scattering element 12 is arranged on the side opposite to the projection device 2 side. Such a hologram screen 1 is attached to the window glass 70 via the adhesive 13. Others are the same as in the first embodiment.

By the way, FIG. 16 shows a hologram screen 7 having the same structure as described above and having no light scattering element 12. For this hologram screen 7, the projection device 2
When the projection light 21 is projected, the projection light 21 is diffracted / scattered by the hologram element 11 and becomes emission light 215, which is emitted from the window glass 70 side. This emitted light 2
An image that can be viewed by the viewer 6 is formed by 15. The emitted light 215 is emitted from the hologram element 11 as described above.
Although there is a spread due to the interference fringes formed in the above, only the center direction of the spread is described in the drawing of this example.

By the way, not all of the projection light 21 is diffracted / scattered, but a part thereof is the hologram element 1.
Pass 1 through. This is the 0th-order light 219. When the observer 6 arrives on the ray of the 0th-order light 219, the 0th-order light 219 is directly incident on the eyes of the observer 6, and glare is felt.

Conventionally, such a problem of glare has been dealt with by arranging a louver filter or the like on the observer 6 side of the hologram element 11 to block the 0th-order light 219.

However, the louver filter also blocks the emitted light that happens to be diffracted and scattered in the same direction as the 0th-order light 219 together with the 0th-order light 219. Therefore, the 0th order light 2
When observing the hologram screen 7 from the same direction as 19, the emitted light does not reach, and there is a problem that the image cannot be seen.

However, in the hologram screen 1 of this example, as shown in FIG. 15, the light scattering element 12 is arranged on the side opposite to the projection device 2. For this reason, the 0th-order light 219 that has passed through the hologram element 11 is scattered by the light scattering element 12, becomes a diffused light 218 that is diffused toward the observer 6 side.

Therefore, it is possible to prevent the observer 6 who is in the same direction as the 0th order light 219 from feeling glare.
Further, the emitted light that reaches from the same direction as the 0th-order light 219 is also diffused, but is not blocked. Therefore, the image does not disappear. It should be noted that this example also has the same effects as the first example.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the use of a hologram screen according to a first embodiment.

FIG. 2 is a diagram showing the scattering characteristics of the light scattering element according to the first embodiment.

FIG. 3 is an explanatory diagram of a measuring system for scattering characteristics of the light scattering element according to the first embodiment.

FIG. 4 is a diagram showing the spectral characteristics of the hologram screen of the present example and the hologram element alone according to the first embodiment.

FIG. 5 is an explanatory view showing the structure of the hologram screen of this example according to the first embodiment.

FIG. 6 is an explanatory diagram showing the effect of the light scattering element in the hologram screen of this example according to the first embodiment.

7A and 7B are explanatory views of a main part of an exposure optical system for producing a hologram element according to the first embodiment, and FIG. 7B is an explanatory view of diffracted light from the hologram element.

FIG. 8 is an explanatory diagram of interference fringes in a hologram element.

FIG. 9 is an explanatory view of a main part in an exposure optical system for producing a hologram element.

FIG. 10 is an explanatory diagram regarding a state of a certain interference fringe in a hologram element and a state of white light interfered by the interference fringe.

FIG. 11 is an angle g larger than the incident angle θr of the reference light applied to the exposure optical system by exposing white light to a certain interference fringe in the hologram element.
Explanatory drawing about the state which was made to enter in.

FIG. 12 is an explanatory diagram showing a method of measuring a light receiving rate according to the second embodiment.

FIG. 13 is an explanatory diagram showing the relationship between the laminated body and the light receiving rate at θ according to the second embodiment.

FIG. 14 is a distribution diagram showing the relationship between the degree of scattering and the state of color reproducibility according to the second embodiment.

FIG. 15 is a cross-sectional explanatory view of a hologram screen having a light scattering element on the side opposite to the projection device according to the third embodiment.

FIG. 16 is an explanatory cross-sectional view of a hologram screen without a light scattering element according to a conventional example.

FIG. 17 is an explanatory view of using a hologram screen according to a conventional example.

FIG. 18 is an explanatory diagram of an exposure optical system for producing a hologram element.

FIG. 19 is an explanatory diagram of a measurement system for spectral characteristics of a hologram element.

FIG. 20 is a diagram showing a spectral characteristic of a hologram element.

[Explanation of symbols]

1. ． ． Hologram screen, 11. ． ． Hologram element, 12. ． ． Light scattering element, 2. ． ． Projection device, 21. ． ． Projection light,

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toru Matsumoto             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO F-term (reference) 2H021 BA27 BA28                 2H042 BA01 BA12 BA14 BA19                 2H049 AA25 AA50 AA60 AA64 CA01                       CA05 CA09 CA15 CA22                 2K008 AA10 EE04 HH19 HH23 HH25

Claims (7)

[Claims] 1. A hologram element having a function of diffracting projection light projected by a projection device, and a light scattering element which is combined with the hologram element and scatters projection light incident within a specific incident angle range. A holographic screen comprising: 2. The hologram screen according to claim 1, wherein the range of the specific incident angle is 25 to 60 °. 3. The hologram screen according to claim 1, wherein the light scattering element has a scattering degree of 5 ° or more. 4. The hologram screen according to claim 1, wherein the light scattering element is arranged on the projection device side. 5. The hologram screen according to claim 1, wherein the light scattering element is arranged on the side opposite to the projection device side. 6. The method according to any one of claims 1 to 5,
A hologram screen, wherein the light-transmitting element has a vertical transmittance of 30 to 100%. 7. The method according to any one of claims 1 to 6,
The light scattering element transmits incident light at least sin ⁻¹ {sin θi−λ1 / λ0 · (sin θo −s
in θr)} ≦ θ ≦ sin ⁻¹ {sin θi−λ2 / λ0 · (sin θ
o −sin θr)} (where, λ0: hologram recording wavelength, λ1 = 380n
m, λ2 = 780 nm [visible light region is 380 to 780 n
m], θr: reference light incident angle, θo: object light incident angle, θ
i: angle θ determined by a mathematical formula for the diffracted light emission angle)
A holographic screen characterized by scattering within a range of.