JP3254365B2 - Multi-image display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-sized multi-image display device for displaying one image by dividing a plurality of liquid crystal panels or by combining and displaying a plurality of images. is there.

[0002]

2. Description of the Related Art Conventionally, as a device for displaying a large multi-image, as shown in a catalog of DIAREX (registered trademark) of Mitsubishi Rayon Co., Ltd., as shown in FIG. For example, there has been a display device that uses a (tube) to divide the image into four partial screens and connect and display images. FIG. 15 shows the internal structure. The divided partial screens 1a to
1d, the projection lenses 2a to 2d and C
RTs 3a to 3d are provided. The distributor 4 receives the image signal I, divides the image signal into quarters, and outputs the divided image signals Ia to Id to the CRTs 3a to 3d. However, boundaries (also referred to as joints) L1 and L2 exist between the partial screens 1a to 1d. Boundary L
1 and L2, the joint between the CRTs is set to be about 1 mm so as to be as inconspicuous as possible. However, since the projected image is displayed across this joint, it is not possible to obtain an image without boundaries (joints). I could not do it.

FIG. 16 is a publication of Japanese Patent Application Laid-Open No. 62-250.
474 is a diagram illustrating a cross-sectional configuration of a rear-projection display device that enlarges and projects a plurality of images on a screen using the liquid crystal panel illustrated in FIG. A plurality of images projected from the projectors 5a and 5b including the liquid crystal panel, the irradiation light source, and the projection lens are combined on the screen 1. The screen 1 is composed of a single transmissive transmissive screen, and has a drawback in that when viewing a projected image obliquely, boundaries (joints) of a plurality of images can be seen due to directivity.

FIG. 17 shows a sectional structure of a screen shown in “Color Liquid Crystal Display” (Display Technology Series, Shunsuke Kobayashi, Sangyo Tosho, P205) in order to improve the characteristics of the single-panel screen used in FIG. FIG. The projection units 20a and 20b include an illumination optical unit 21.
a, 21b, liquid crystal panels 22a, 22b, projection lens 2
3a and 23b are provided. Illumination optics 21a, 2
1b is for irradiating the liquid crystal panel, and the projection lenses 23a and 23b
This is a lens that projects onto the screen 1 via 4a and 24b. The screen 1 includes a plurality of partial Fresnel lenses (also simply referred to as Fresnel lenses) 11a and 11b and one diffusion plate 13 or a lenticular plate.
The Fresnel lens and the diffusion plate or the lenticular plate are in close contact.

FIGS. 18 and 19 illustrate the operation of the Fresnel lens, taking as an example the case where there are two projection units. In FIG. 18, the image of the liquid crystal panel by the projection unit 20a is enlarged and projected on the portion A of the diffusion plate 13 to generate a projection image 30A. on the other hand,
Similarly, the image of the liquid crystal panel by the projection unit 20b is enlarged and projected on the portion B of the diffusion plate 13 and the projected image 3
0B is generated. Pixels of Projected Image 30A and Projected Image 30
The boundaries of the pixels of B correspond to the corresponding projection units 2
By adjusting 0a and 20b, the connection is assumed to be seamless. In FIG. 18, when the observer M is located substantially at the center of the projection image 30A and views the projection image 30A and the projection image 30B at the same time, attention is paid to the boundary between the projection image 30A and the projection image 30B. As shown in FIG.
When there is no Fresnel lens, the projected image 30A and the projected image 30B are respectively diffused by the diffusion plate, but the luminous flux projected by the projection unit has a spread, so that the projected image 30A and the projected image 30B are respectively diffused. It is not evenly diffused by the plate. Looking at the boundary between the projected image 30A and the projected image 30B from the observer M,
The amount of direct light indicated by arrows F and G from the projection units 20a and 20b is larger than the amount of light indicated by arrow K diffused by the diffusion plate, and the brightness of the projected image 30B is higher than that of the projected image 30A. It grows larger, becomes shaded, and the border becomes visible. As shown in FIG. 19, when there is a Fresnel lens, a light beam having a spread from each projection unit is converted into a substantially parallel light beam by the Fresnel lens, and is incident on the diffusion plate. Since the light beam incident on the diffusion plate is almost perpendicular to the diffusion plate, the light beam is uniformly diffused at any position on the diffusion plate as indicated by the arrow K. For this reason, the projected image 30A and the projected image 30B
Are almost the same at the boundary portion of, and the shadow becomes smaller.

FIG. 20 is a diagram showing a boundary between Fresnel lenses when a plurality of Fresnel lenses are used. It is necessary to adjust the optical paths of the outermost light beams F and G so that the outermost light beams F and G enter the boundary between the Fresnel lenses 11a and 11b. Further, even if the outermost light beams F and G are adjusted so as to be incident on the very border of the Fresnel lenses 11a and 11b, the Fresnel lenses 11a and 11b
There is a case where the outermost light fluxes F and G are not continuously displayed on the screen 1 due to the presence of an adhesive or a bonding agent between them. Alternatively, if the manufacturing accuracy of the Fresnel lens is not high, a gap may occur between the Fresnel lenses 11a and 11b, and the images of the outermost light beams F and G may not be continuously formed on the screen.

FIG. 21 shows an example of a projection image. In this example, a 2 × 2 portion at the center of a 4 × 4 image is shown. At the boundary of the projected image, a space is generated, so that the pixels cannot be continuously connected at the same pitch as the inside of each projected image at the boundary of the projected image. As described above, even when the Fresnel lens is provided, it is difficult to completely connect the images without a break, and there is a disadvantage that a boundary is formed in the projected image.

FIG. 22 is a front view of a Fresnel lens when a plurality of integrated Fresnel lenses expand and contract due to a temperature change or the like. When the temperature changes, the center of the Fresnel lens moves in an oblique direction. For example, if the Fresnel lens is made of acrylic, its linear expansion coefficient is
A 6x10 ^-5 ~8x10 ^-5, the overall diagonal dimension of the plurality Fresnel lens integrated is 60 inches, the temperature is by about 2mm stretch across the diagonal direction when varying 20 degrees. The center and boundary of the Fresnel lens move according to the expansion and contraction. For example, the center of the Fresnel lens moves from point C to point S. Also, the boundary of the Fresnel lens moves from the line P to the line Q. FIG. 23 shows a cross section of a screen for explaining the movement of a light beam near an adjacent Fresnel lens when the Fresnel lens expands and contracts due to a temperature change or the like. If the Fresnel lens expands and contracts due to temperature changes, the boundary position of the Fresnel lens moves, and the conventional screen has a drawback that the projected image goes around the adjacent Fresnel lens and crosstalk occurs between the projected images. Was. For example, in the drawing, light indicated by T is light to be incident on the Fresnel lens 11a, but the boundary position of the Fresnel lens is shifted from the line P to the line Q
, The light enters the Fresnel lens 11b and crosstalk occurs. T
The light indicated by is incident upon the Fresnel lens 11b whose angle is changed and the degree of perpendicularity to the diffusion plate is rather deteriorated.

[0009]

The display device using a plurality of CRTs shown in FIGS. 14 and 15 has a drawback that boundaries (joints) L1 and L2 are formed in the divided partial screens 1a to 1d. there were.

The display device using a plurality of liquid crystal panels and a single panel screen shown in FIG. 16 has a drawback that when viewed from an oblique direction, the boundaries (joints) of the multiple images are visible due to the directivity of the single panel screen. was there.

In the conventional screen shown in FIG. 17, it is difficult to connect the pixels at the boundary between the projected image 30A and the projected image 30B without a break, and there is a disadvantage that the projected image has a boundary.

Further, the conventional screen shown in FIG. 22 has a drawback that a projected image wraps around an adjacent Fresnel lens and crosstalk occurs between the projected images.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to obtain a multi-image display device capable of generating a large image without joints or crosstalk. .

[0014]

A multi-image display apparatus according to the present invention combines a plurality of projection units for generating partial images constituting a part of an image with the partial images generated from the plurality of projection units. In the multi-image display device having a screen for displaying the image, the screen includes a plurality of partial Fresnel lenses provided corresponding to the plurality of projection units, and a single diffusion plate including a diffusion material. In addition, a space of a certain length is provided between the plurality of partial Fresnel lenses and the diffusion plate.

One transparent spacer is provided between the plurality of partial Fresnel lenses and the diffusion plate.

The transparent spacer and the diffusion plate are integrated.

A plurality of partial Fresnel lenses are integrated.

A plurality of partial Fresnel lenses, a transparent spacer, and a diffusion plate are integrated.

An antireflection film is provided on all or a part of the plurality of partial Fresnel lenses, transparent spacers, and diffusion plates.

The integrated Fresnel lens is fixed at the center of each side of the integrated Fresnel lens.

The length of the space is set so that a plurality of images generated from the plurality of projection units enter only corresponding Fresnel lenses.

The projection unit is provided with an adjusting mechanism for a plurality of axes.

The adjusting mechanism includes an optical axis of the projection unit,
The optical axis of the projection unit is controlled so that the optical axis of the partial Fresnel lens corresponding to the projection unit coincides.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a perspective view showing an example of a multi-image display device of the present invention when viewed from the front,
FIG. 2 is a perspective view when viewed from the back. FIGS. 1 and 2 show a state where the screen 1 is removed to display the internal structure. When an image is actually displayed, the screen 1 covers the entire front surface of the multi-image display device 100. In the example shown in FIGS. 1 and 2, the projection units 20 are arranged in a 4 × 4 array, and the projection units 2
0 are arranged on the cabinet 101 by the adjustment stage 150, respectively. The projection unit 20 receives an image signal from the control unit 160. Projection unit 20
Is projected from behind the screen 1 via the reflecting mirror 40. Further, in this example, illumination light to the projection unit is supplied from an optical fiber 41 from a light source provided in a lamp box (not shown).

FIG. 3 shows an example of the screen 1 according to the present invention. Projection units 20a, 20b
Have illumination optics 21a, 21b, liquid crystal panel 22a,
22b, and projection lenses 23a and 23b are provided.
The illumination optical units 21a and 21b illuminate the liquid crystal panel, and the projection lenses 23a and 23b are lenses that project an image from the liquid crystal panel onto the screen 1 via exit pupils 24a and 24b. The screen 1 includes a plurality of partial Fresnel lenses (also simply referred to as Fresnel lenses) 11 a and 11 b, a transparent spacer 12 and a diffusion plate 13.
It is composed of The focal position of the Fresnel lenses 11a, 11b is determined by the exit pupil 24 of the projection lenses 23a, 23b.
a, 24b. Projection lens 23a,
The projected image from 23b may be substantially emitted from the exit pupils 24a and 24b as a divergent light beam. Exit pupil 2
The divergent light beams from 4a and 24b are
By being incident on a and 11b, the light is converted into a substantially parallel light beam, passes through the transparent spacer 12, and forms an image on the diffusion plate.

FIG. 4 is for explaining the operation and effect of the transparent spacer 12 in the configuration of the screen 1 according to the present invention. By providing the transparent spacer 12 between the Fresnel lenses 11a and 11b and the diffusion plate 13, the outermost light fluxes F and G forming the projected images incident on the Fresnel lenses 11a and 11b are provided for forming a plurality of images. The outermost luminous fluxes F and G can be guided to a continuous position of the diffusion plate 13 without being incident on the border of the adjacent Fresnel lenses 11a and 11b. The outermost luminous fluxes F and G are applied to the Fresnel lenses 11a and 11b by the width W.
Incident. Fresnel lenses 11a and 11b
The outermost light beams F and G are converted into substantially parallel light beams. In this embodiment, complete parallel light beams are not used, but completely parallel light beams as shown by light F1 and G1 indicated by arrows. Uses unconverted light. The light F1, G1 has a width U
Are output from the Fresnel lenses 11a and 11b. Light F output from Fresnel lenses 11a and 11b
Similarly, G2 and G2 are not perfectly parallel beams but are emitted in directions approaching each other. Light F2 applied to diffusion plate 13
And G2 will have a width V. If the width V is the same as the pitch at which pixels are displayed, images can be displayed continuously. The transparent spacer 12 is for making the light F2 and G2 have a width V. That is, the transparent spacer 12
The width V can be adjusted by changing the thickness D of. The transparent spacer 12 includes a Fresnel lens 11a,
This is to convert the emission width U of 11b into a pixel width V to be displayed on the diffusion plate 13. By adjusting the thickness D of the transparent spacer 12, the conversion ratio from the width U to the width V can be adjusted.
As a result, the width W at which the outermost light beams F and G are incident can be adjusted. That is, by providing the transparent spacer 12, the irradiation position of the outermost light fluxes F and G can be set to the Fresnel lens 11
It is not necessary to be incident on the very edge of the boundary between a and 11b. Thus, by providing the transparent spacer 12, a margin for image formation can be provided between the emission surfaces of the Fresnel lenses 11a and 11b and the diffusion plate. Further, the outermost light beams F and G do not enter the boundary between the Fresnel lenses 11a and 11b, and joints generated from the joint of the Fresnel lenses can be eliminated. By adjusting the positions of the projection units 20a, 20b and the projection lenses 23a, 23b, the position between adjacent projection images can be easily adjusted.

Although the Fresnel lenses 11a and 11b convert divergent light beams into substantially parallel light beams, in this embodiment, the Fresnel lenses 11a and 11b cannot completely convert divergent light beams into parallel light beams, or The feature is that it actively utilizes the fact that it does not convert. FIG.
F1 and G1 shown in FIG.
Are divergent light beams that have not been converted into parallel light beams or have not been converted. As described above, the transparent spacer 12 is provided in order to display continuous pixels using light that is not converted into a complete parallel light beam or light that is not converted. An adhesive or a bonding agent exists between the Fresnel lenses 11a and 11b. Also, the Fresnel lens 11
If the manufacturing accuracy of a and 11b is not high, a space may be created between the Fresnel lenses 11a and 11b. That is, the boundary between the Fresnel lenses 11a and 11b is considered to be a part that does not function as a Fresnel lens, and it is desirable that the boundary between the Fresnel lenses 11a and 11b is not used as much as possible. Also,
In order to allow light to enter just below the boundary between the Fresnel lenses 11a and 11b, it is necessary to accurately adjust the positions of the projection unit and the projection lens. In this embodiment, images can be continuously displayed on the screen without using the boundary between the Fresnel lenses 11a and 11b.

In this embodiment, as described above, light which is not converted into a parallel light beam is actively used, so that the Fresnel lenses 11a and 11b of this embodiment are used.
It is more desirable to convert the light incident on the boundary portion into a non-parallel light beam, rather than into a parallel light beam, rather than into a parallel light beam, such as the light beams F1 and G1 shown in FIG. Fresnel lenses 11a and 11b of this embodiment
May be manufactured in advance as described above. That is, the Fresnel lenses 11a and 11b of this embodiment
May be manufactured so as not to convert the light incident on the peripheral portion into a parallel light beam, but to simply change the optical path. Alternatively, the Fresnel lenses 11a and 11b are manufactured and converted as described above to convert the divergent light beam into a parallel light beam, and the exit pupils 24a and 24b of the projection lenses 23a and 23b are shifted from the focal positions of the Fresnel lenses 11a and 11b.
b may be placed at a position closer to the Fresnel lenses 11a and 11b. The exit pupils 24a, 24b of the projection lenses 23a, 23b are set higher than the focal positions of the Fresnel lenses 11a, 11b.
When 24b is near the Fresnel lenses 11a and 11b, the divergent light beams emitted from the exit pupils 24a and 24b are:
The light is converted into a light beam whose divergence angle is weakened by the Fresnel lenses 11a and 11b. Therefore, as shown in FIG. 4, the outermost luminous fluxes F and G are emitted from the Fresnel lenses 11a and 11b as divergent luminous fluxes whose optical paths are slightly changed. Has an effect.

FIG. 5 shows an example of a projection image according to the present invention. In this example, a 2 × 2 portion at the center of a 4 × 4 image is shown. By providing the transparent spacer 12, pixels forming adjacent images of the projection image 1 to the projection image 4 can be continuously connected at the same pitch.

FIG. 6 is a diagram showing another example of the screen according to the present invention. The difference between the configuration shown in FIG. 6 and the configuration shown in FIG. 4 is that a space (space) is provided instead of inserting the transparent spacer 12 in order to provide a gap between the Fresnel lenses 11 a and 11 b and the diffusion plate 13. . By providing this space, the outermost luminous flux incident on the Fresnel lens and forming a projected image is converted into a plurality of Fresnel lenses 11a and 11 provided for forming a plurality of images.
The light can be guided to a continuous position on the diffusion plate 13 without being incident on the very border of the adjacent boundary 1b.

FIG. 7 is a view showing another example of the screen according to the present invention. The difference between the configuration shown in FIG. 7 and the configuration shown in FIG. 4 is that a diffusion plate 15 in which the transparent spacer 12 and the diffusion plate 13 are integrated is provided. The transparent spacer and the diffusion plate can be made of, for example, acrylic. By forming a diffusion portion in which a diffusing agent is mixed with transparent acrylic and a transparent portion 15a which remains transparent, the transparent spacer and the diffusion plate can be integrated and manufactured. As described above, the transparent portion 1 is provided on the incident side of the diffusion plate 15.
By providing 5a, the outermost luminous flux that forms the projection image incident on the Fresnel lens does not enter the boundary between the adjacent Fresnel lenses 11a and 11b provided for forming the plurality of images. Diffuser 1
It is possible to lead to three consecutive positions.

FIG. 8 is a view showing another example of the screen of the present invention. The difference between the configuration shown in FIG. 8 and the configuration shown in FIG. 7 is that the Fresnel lenses 11a and 11b are integrated with the transparent portion 15a of the diffusion plate 15 provided with the transparent portion 15a. As described above, by providing the transparent portion 15a on the incident side of the diffusion plate 15, the outermost luminous flux incident on the Fresnel lens and forming a projection image can be converted into a plurality of Fresnel lenses 11a provided for forming a plurality of images. , 1
The light can be guided to a continuous position on the diffuser plate without being incident on the very border of the boundary 1b. Further, by integrating the Fresnel lens, the transparent spacer, and the diffusion plate, it is possible to eliminate the two interfaces of the interface between the Fresnel lens and the transparent spacer and the interface between the transparent spacer and the diffusion plate, and to eliminate the reflection generated at these interfaces. be able to. In addition, since the number of components can be reduced by integrating, the screen can be made inexpensive.

By providing an anti-reflection film on both sides (total of six places) of each of the Fresnel lens, the transparent spacer and the diffusion plate constituting the above-mentioned screen, a projected image with better contrast and less light loss can be obtained. .
An anti-reflection film may be applied to two places on both sides of the screen and / or two places on the boundary between the Fresnel lens, the transparent spacer, and the diffusion plate. Alternatively, an antireflection film may be applied to any one of the locations.

FIG. 9 is a diagram showing an example of the multiple Fresnel lens of the present invention. FIG. 10 is a diagram showing a manufacturing example of the one-dimensional Fresnel lens array of the present invention. Fresnel lenses are usually manufactured using a mold. For example, it is manufactured by press working of plastics using a mold, ultraviolet curing of liquid plastic, or the like. Since one Fresnel lens has a concentric saw-tooth shape, when the Fresnel lens is removed from the mold, it must be peeled from the periphery of the Fresnel lens. In the multiple Fresnel lens according to the present invention, as shown in FIG. 10, a metal mold is connected in a lateral direction to manufacture a strip-shaped one-dimensional Fresnel lens array integrally manufactured. Then, the strip-shaped one-dimensional Fresnel lens array manufactured integrally is bonded to form a two-dimensional array. When the Fresnel lens is removed from the mold, as shown in FIG. 10, the Fresnel lens is peeled off by applying a force in the direction of arrow H. If a force is applied in the direction of arrow I to detach the Fresnel lens from the mold, in the saw-tooth region S,
Although it can be peeled off neatly, it cannot be peeled off at the serration R, and the serration may be damaged. Therefore, when two-dimensionally arranged Fresnel lenses are manufactured at a time using two-dimensionally arranged dies, the Fresnel lens cannot be removed from the mold. In this embodiment, FIG.
As shown in the figure, since the mold is connected in one dimension,
By applying a force in the direction of arrow H, the Fresnel lens can be removed from the mold. Also, the reason why the Fresnel lens is integrally molded in the horizontal direction and then glued in the vertical direction to form a two-dimensional array is that the seam is better in the horizontal direction than in the vertical direction because of the visual characteristics of the eyes. Is difficult to see,
This is because a multi-image display device with small joints can be obtained.

FIG. 11 shows a method for fixing a Fresnel lens according to the present invention. When a plurality of partial Fresnel lenses provided corresponding to a plurality of projection units are integrated, two orthogonal Fresnel lenses passing through the center of the integrated Fresnel lens
The integrated Fresnel lens is fixed on the reference lines C1 and C2. That is, the integrated Fresnel lens is fixed at the center of each side of the integrated Fresnel lens. In the integrated Fresnel lens, 103 is provided.
03 from the cabinet 101 to the reference lines C1 and C
Along 2, a shaft 104 is engaged. FIG. 12 is a view showing the expansion and contraction state of the Fresnel lens when the integrated Fresnel lens is fixed on the reference lines C1 and C2. By fixing the Fresnel lens in this way, even if the Fresnel lens expands or contracts due to a temperature change or the like, two orthogonal reference lines can be secured, so that the position of the projected image at the center does not change. The center position of the Fresnel lens in the peripheral part moves due to a change in temperature, causing a shift from the optical axis of the corresponding projection unit, and the projected image from the projection unit is obliquely incident on the Fresnel lens, but the angle is integral. This is smaller than the case where there is a reference line in the peripheral portion of the converted Fresnel lens, and the position change of the image projected on the diffusion plate can be ignored. For example, if the focal length of the Fresnel lens is 260 mm and the temperature change is 20 degrees, the change in the projection angle is 3.7 mrad, and if the thickness of the transparent spacer is 1 mm, the movement amount of the projected image is 3.
It is only 7 μm. The amount of movement of the projected image is shown in FIG.
Is less than or equal to 1/2 of the interval W between the outermost light beams F and G, for example, the outermost light beam F does not enter the Fresnel lens 11b. Alternatively, the outermost light flux G does not enter the Fresnel lens 11a. That is, no crosstalk occurs. In the present invention, since the transparent spacer is inserted between the Fresnel lens and the diffusion plate, it is not necessary to irradiate the outermost luminous fluxes F and G just below the boundary of the Fresnel lens. Since the outermost luminous fluxes F and G are not radiated just below the boundary of the Fresnel lens, the projected image does not go around the adjacent Fresnel lens. Further, by fixing the integrated Fresnel lens at the center of each side in this manner, even if the temperature changes, the amount of change is reduced by half, so that a multi-image display without joints can be obtained.

FIG. 13 shows an adjusting mechanism of the projection unit according to the present invention. The projection unit is mounted via an adjustment stage 150 mounted on the cabinet 101 and independently movable in each of the X, Y, and Z axes, a mounting arm 151, and a gonio stage 152 mounted on the mounting arm. The adjustment stage 150, which can be independently moved in each of the X, Y, and Z axes, translates the projection image from the projection unit in the X and Y directions with respect to the surface of the screen 1 and moves back and forth in the Z direction. By doing so, the size of the projection image is set to a predetermined size. Goniometer stage 152
Has a function of rotating the projection image from the projection unit in the θ direction with respect to the optical axis L of the projection unit, and rotating the projection image in the ψ direction with respect to an axis M perpendicular to the optical axis L. By adjusting the five axes X, Y, Z, L, and M, a plurality of images projected on the screen 1 can be connected without joints.

Further, when the position of the Fresnel lens moves due to a temperature change according to a signal from a sensor (not shown) that senses the boundary between adjacent projection images, the adjustment stage 150 and the gonio stage 152 always move the projection unit. The control is performed so that the optical axis and the optical axis of the corresponding Fresnel lens coincide. In this way, by performing feedback control on the projection unit, even when the position of the Fresnel lens moves due to a temperature change, joints are not generated at the boundary between adjacent images, and a continuous multi-image is obtained.

In the above embodiment, the liquid crystal panel 2
Although the case where only one 2a is arranged inside the projection unit has been described, a case where a plurality of liquid crystal panels are arranged inside one projection unit may be used. For example,
A liquid crystal panel may be arranged for each of red, blue, and green, and a projection unit that generates an image by combining them may be used.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a multi-image display device of the present invention when viewed from the front.

FIG. 2 is a perspective view showing an example of the multi-image display device of the present invention when viewed from the back.

FIG. 3 is a diagram showing an example of the screen of the present invention.

FIG. 4 is a diagram for explaining the operation and effect of the transparent spacer 12 in the configuration of the screen 1 according to the present invention.

FIG. 5 is a diagram showing an example of a projection image according to the present invention.

FIG. 6 is a diagram showing another example of the screen according to the present invention.

FIG. 7 is a diagram showing another example of the screen according to the present invention.

FIG. 8 is a diagram showing another example of the screen according to the present invention.

FIG. 9 is a diagram showing an example of a multiple Fresnel lens according to the present invention.

FIG. 10 is a diagram showing a manufacturing example of the one-dimensional Fresnel lens array of the present invention.

FIG. 11 is a diagram showing a fixing method of the Fresnel lens of the present invention.

FIG. 12 is a diagram showing expansion and contraction of a Fresnel lens when the method for fixing a Fresnel lens of the present invention is used.

FIG. 13 is a diagram showing an adjustment mechanism of the projection unit according to the present invention.

FIG. 14 is a diagram illustrating an image display device using a conventional CRT.

FIG. 15 is a diagram showing a conventional multi-image display device using a CRT.

FIG. 16 is a view showing a conventional multi-image display device using a liquid crystal.

FIG. 17 is a view showing a conventional screen.

FIG. 18 is a diagram illustrating the operation of a Fresnel lens.

FIG. 19 is a diagram illustrating the operation of a Fresnel lens.

FIG. 20 is a diagram illustrating an operation when a Fresnel lens is used.

FIG. 21 is a diagram illustrating an example of a conventional projection image.

FIG. 22 is a front view of the Fresnel lens when the Fresnel lens expands and contracts due to a temperature change or the like.

FIG. 23 is a view showing a cross section of a screen for explaining movement of a light beam near an adjacent Fresnel lens when the Fresnel lens expands and contracts due to a temperature change or the like.

[Explanation of symbols]

Reference Signs List 1 screen, 11 Fresnel lens, 12 transparent spacer, 13 diffuser, 14 space, 15 spacer integrated diffuser, 20 projection unit, 21 illumination optical unit, 22 liquid crystal panel, 23 projection lens, 24 exit pupil, 100 multi-image display device , 101 cabinet, 150 adjustment stage, 151 mounting arm,
152 Goniometer stage.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02F 1/13 G03B 21/132 G03B 21/56

Claims (10)

(57) [Claims] 1. A multi-image display device comprising: a plurality of projection units for generating partial images constituting a part of an image; and a screen for combining and displaying the partial images generated from the plurality of projection units. The screen is composed of a plurality of partial Fresnel lenses provided corresponding to a plurality of projection units, and one diffusion plate including a diffusion material, wherein the plurality of partial Fresnel lenses and the diffusion plate provided space constant length between, the image is composed of pixels arranged in a predetermined pixel pitch, the plurality of projection units irradiates a divergent light beam from the inner boundary portions of the respective portions off Les Nerurenzu, The partial Fresnel lens outputs the divergent light beam without making the outermost light beam of the emitted divergent light beam into a parallel light beam. The thickness <br/> of space between the spacing of the pixels to be generated on the diffusion plate by the outermost beams of the adjacent irradiated to adjacent portions Fresnel lens the light flux is set so that the pixel pitch A multi-image display device. 2. The multi-image display device according to claim 1, wherein one transparent spacer is provided between the plurality of partial Fresnel lenses and the diffusion plate. 3. The multi-image display device according to claim 2, wherein the transparent spacer and the diffusion plate are integrated. 4. The multi-image display device according to claim 1, wherein said plurality of partial Fresnel lenses are integrated. 5. The multi-image display device according to claim 2, wherein said plurality of partial Fresnel lenses, a transparent spacer, and a diffusion plate are integrated. 6. The multi-image display device according to claim 2, wherein an anti-reflection film is applied to all or a part of the plurality of partial Fresnel lenses, transparent spacers, and diffusion plates. 7. The multi-image display device according to claim 4, wherein the integrated Fresnel lens is fixed at the center of each side of the integrated Fresnel lens. 8. The thickness of the space is set so that a plurality of images generated from the plurality of projection units enter only corresponding Fresnel lenses, respectively. 2. The multi-image display device according to 1. 9. The multi-image display device according to claim 1, wherein said projection unit is provided with an adjustment mechanism in a plurality of axial directions. 10. The adjusting mechanism controls an optical axis of the projection unit such that an optical axis of the projection unit coincides with an optical axis of a partial Fresnel lens corresponding to the projection unit. 10. The multi-image display device according to 9.