JP2000330200A - Optical unit for projection optical system or the like, manufacture thereof and display device provided with the unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device small in size and capable of obtaining a satisfactory enlarged image at high quality, and to provide components therefor. SOLUTION: This display device is provided with a projecting optical system 301, a liquid crystal panel 201, an enlarging optical system 401 for enlarging an image, a collimating optical system 501 for collimating divergent light emitted from the enlarging optical system. 1st and 2nd lens arrays 602 and 603 for receiving the light emitted from the collimating optical system 501, a converging system 701 for receiving the light emitted from the lens array group 601 and emitting the convergent light, and a display screen 801 for receiving the light emitted from the converging system 701. By arranging the collimating optical system 501 on the image generating means side of the lens array group 601, the deterioration of image quality is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection optical system for projecting an image, and more particularly to a projection optical system used for a direct-view display device capable of obtaining a similar image with high quality.

[0002]

2. Description of the Related Art Flat display devices represented by liquid crystal display devices have come to be used in various fields by utilizing the features of light weight, thinness, and low power consumption. Among them, personal
Liquid crystal display devices are frequently used in portable information devices represented by computers.

[0003] However, in such a liquid crystal display device, an insulating substrate such as glass is used, but it is difficult to realize a large display area of 20 inches or more due to restrictions of the substrate and restrictions of a manufacturing apparatus. Met. Therefore, a technique for forming a large display area by bonding a plurality of liquid crystal panels together is known from Japanese Patent Application Laid-Open No. 8-146455.

[0004]

However, in such a large display screen by bonding display panels, an improvement in image quality has been demanded because the joint is visually recognized as a portion where an image is missing.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned technical problems, and can be reduced in size to realize a sufficiently enlarged image.
It is another object of the present invention to provide a projection optical system capable of projecting a high-quality similar image, a method of manufacturing the same, and a display device using the same.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has an image generating means having a predetermined effective generating area for generating a light beam corresponding to an image; A display screen having an image display area larger than the effective generation area of the image generation means, and an optical system for projecting the image of the image generation means on the display screen, wherein at least the An optical system disposed between the image generating means and the display screen, a collimating optical system that receives the light beam and converts the light beam into substantially parallel light, and a first lens array including a plurality of first lenses; A second lens array of a plurality of second lenses corresponding to the plurality of first lenses, and a projection optical system for projecting the light beam onto a display screen. It is shown apparatus.

At this time, the image generating means is of a field emission display (FED) or a light transmission type, and it is preferable that a light source is disposed on a side of the image generating means facing the display screen.

In the case of the FED, the density of the projections corresponding to at least the pixels at the periphery of the effective generation area of the field emission display is higher than the density of the projections corresponding to the pixels at the center of the effective generation area. Preferably, it is formed.

In the case of the light transmission type, the light source includes a diffusion light source unit,
It is preferable to include parallel light projection means for collimating and projecting the light from the diffusion light source unit. Preferably, at least one enlargement optical system for enlarging an image emitted from the projection optical system is provided between the projection optical system and the display screen. Further, it is preferable that an enlargement optical system or a reduction optical system is disposed between the image generating means and the parallelizing optical system.

It is preferable that a convergence system for converging a light beam emitted from the projection optical system to the main surface of the display screen is provided. Further, it is preferable that the luminance of the light beam emitted from the image generating means is set to be higher near the periphery than in the center of the cross section of the light beam.

The optical system may include a Fresnel lens in which a surface substantially parallel to the optical axis direction is formed coarser than other optical surfaces, or the optical system may include a light absorbing surface that is substantially parallel to the optical axis direction. It is preferable to provide a Fresnel lens on which a conductive film is formed.

Further, the present invention provides a collimating optical system for receiving an image and converting it into substantially parallel light, a first lens array in which a plurality of first lenses are juxtaposed with respect to the collimating optical system, A second lens array in which a plurality of second lenses corresponding to the first lens are arranged side by side, and a projection optical system that projects the image on an object to be projected. At this time, the parallelism of the parallel light is preferably a divergence angle within the angle of view of the first lens.

The present invention further provides a step of combining a set of lens arrays capable of receiving an image of an object plane and projecting an erect image of the image to a position at the same distance from the object plane; Combining a collimating optical system that receives a light beam constituting the light beam and emits a light beam having a divergence angle within the angle of view of the lens constituting the lens array with the set of lens arrays. This is a method for manufacturing a projection optical system.

Furthermore, the present invention is an image generating means having a higher luminance near the periphery than at the center of the image. Further, according to the present invention, in a method of manufacturing an image generating means having a step of forming an effective generation area for generating an image, the luminance is adjusted so as to be higher near the periphery than near the center of the surface forming the effective generation area. Forming the effective generation area.

Further, according to the present invention, the projections corresponding to the pixels at the periphery of the effective generation area of the image have a higher density of projections than the projections corresponding to the pixels at the center of the effective generation area. It is a field emission display characterized by the following.

Further, the present invention provides a method for manufacturing a field emission display comprising a step of combining a cathode device having a projection for emitting electrons with an anode device for attracting electrons emitted from the cathode device to a fluorescent layer. The density of the projections of the projection group corresponding to the pixels at the periphery of the effective generation area, the cathode device formed so as to be larger than the projection group corresponding to the pixels at the center of the effective generation area of the image and the anode layer value and A method for manufacturing a field emission display, comprising a step of combining.

Further, the present invention is the liquid crystal display device, characterized in that a light source is provided in which the brightness of the emitted light beam is higher in the vicinity of the cross section of the light beam than in the vicinity of the center. Furthermore, the present invention provides a method of manufacturing a liquid crystal display device having a step of combining a liquid crystal panel and a light source, wherein the light source is such that the luminance of the emitted light is higher in the vicinity of the periphery than in the vicinity of the center of the cross section of the light. A method for manufacturing a liquid crystal display device, comprising a step of providing.

The present invention further provides a lens array in which the optical surfaces of a plurality of lenses are juxtaposed in substantially the same plane and integrally formed, and the optical surfaces of the lens array are juxtaposed in substantially the same plane. It is.

Further, the present invention is characterized in that the method further comprises a step of integrally forming the optical surfaces of the lens array formed by juxtaposing the optical surfaces of the plurality of lenses in substantially the same plane. This is a method for manufacturing a lens array.

Further, according to the present invention, a surface substantially parallel to the optical axis direction is formed coarser than other optical surfaces, or a light absorbing film is formed on a surface substantially parallel to the optical axis direction. Is a Fresnel lens.

Further, according to the present invention, an optical system provided in the display device is formed so as to be configurable, and a surface substantially parallel to the optical axis direction is formed coarser than other optical surfaces, or A Fresnel lens characterized in that a light-absorbing film is formed on a surface substantially parallel to the lens. Hereinafter, the present invention will be described in detail based on specific embodiments, but the present invention is not limited to the following embodiments.

[0022]

Embodiments of the present invention will be described with reference to the drawings. The liquid crystal display device illustrated in FIG. 1 includes a light projecting optical system 301, a liquid crystal panel 201 that receives light from the light projecting optical system 301 and visualizes the light, and supplies a drive signal to the liquid crystal panel 201 (not shown). A drive circuit board, an enlargement optical system 401 disposed on the surface side from which an image is emitted from the liquid crystal panel 201, and a collimating optical system 501 for collimating divergent light emitted from the enlargement optical system
And a lens array group 601 including first and second lens arrays 602 and 603 that receive light emitted from the parallelizing optical system 501, and convergent light that emits convergent light upon receiving light emitted from the lens array group 601. System 701 and a display screen 8 for receiving light emitted from the converging system 701
01 is provided.

The display device of the present embodiment has a liquid crystal display (LCD) as an image generating means.
y), that is, the liquid crystal panel 201 and its light projecting optical system 30
Since No. 1 is used, the details will be described first.

The liquid crystal panel 201 shown in FIG.
It has an effective display area PS with display pixels of inch (vertical (1024 × 3) × width 768). This liquid crystal panel 201 has a thin film transistor (TFT) in which a polycrystalline silicon (p-Si) thin film is used as an active layer as a switch element for controlling each pixel as shown in FIG. : Thin Film Transistor) 121, a counter substrate 151, and an alignment film 1 between the array substrate 111 and the counter substrate 151.
TN liquid crystal layer 191 held via 83a, 183b
And Also, the outer surfaces of the substrates 111 and 151 are provided on the outer surfaces of the deflection plates 185a and 185 so that the transmission axes are orthogonal to each other.
b is arranged.

The array substrate 111 is composed of 1024 × 3 signal lines and 768 scanning lines and 768 scanning lines (not shown) arranged in a matrix on a 0.7 mm thick transparent insulating substrate 113 made of glass. A TFT 121 as a switch element arranged near the intersection of the
And a pixel electrode 131 connected to the FT 121.

Further, the TFT 121 is formed in the channel region 12.
3c, a polycrystalline silicon (p-Si) film 123 having source and drain regions 123d and 123s arranged with the channel region 123c interposed therebetween, and a gate insulating film on the channel region 123c of the p-Si film 123. 125
And a source / drain region 123s, 123
d and the source and drain electrodes 127 respectively connected to
s, 127d. This gate electrode 11
8 is connected to the scanning line, the drain electrode 127d is connected to the signal line, and the source electrode 127s is connected to the pixel electrode 131, respectively.

The pixel electrode 131 is formed on the color filter layer 18 also serving as an interlayer insulating film disposed on the TFT 121.
1 above. The opposing substrate 151 includes an opposing electrode 155 made of an ITO (Indium Tin Oxide) film opposing the pixel electrode 131 on a 0.5 mm thick transparent insulating substrate 153 made of glass.

The color filters 181 are formed on the array substrate 111. As a method of realizing a color display, a color filter is additionally provided on the array substrate 111,
Alternatively, it can be formed on the opposing substrate 151, and there is a method of performing display by dividing each field period into each color period and driving them.

The liquid crystal panel 20 thus constructed
The light projecting optical system 301 disposed on the back side of the light guide plate 1 has a thin light guide plate 311 made of acrylic resin as shown in FIG. And cold cathode tubes 321 arranged in two stages.

On the surface of the light guide plate 311, for example, two layers of prism sheets 331 made by 3M are arranged to make the diffused light from the light guide plate 311 relatively uniform parallel light. Thus, the angle between the main surface of the liquid crystal panel 102 and the normal direction to the main surface of the liquid crystal panel 102, which is determined by the half width of the luminance of the light emitted from the liquid crystal panel 201, is controlled to about 25 °. On the light incident surface side of the light guide plate 311, a milky white dot pattern (not shown) is formed by printing so that light propagating through the light guide plate 311 is selectively emitted from the main surface.

In this embodiment, in order to make the display brightness of the image on the display screen of the liquid crystal display device as the image generating means uniform, relatively high brightness is achieved in the peripheral region of the light guide plate 311. A dot pattern is formed on the substrate. This is because the peripheral area of the display screen 801 has a smaller number of working channels than the central area, and therefore a reduction in luminance is inevitable. The light projecting optical system 301 which is a surface light source unit is used to offset this. Is adjusted.

Next, an optical system arranged on the surface from which an image is emitted from the liquid crystal panel 201 will be described.
A light beam constituting a desired image emitted from the liquid crystal panel 201 enters the magnifying optical system 401 composed of a concave lens, and the magnified light beam enters the collimating optical system 501 composed of a convex lens collimator lens and becomes substantially parallel. It is converted into a luminous flux. The degree of parallelism of the parallel light beam corresponds to the angle of view of the projection optical system 601 formed by the next-stage lens array group. It is difficult to increase the angle of view of each lens of the first and second lens arrays 602 and 603 constituting the projection optical system 601 due to the lens design. Therefore, unless the divergence angle of the light beam emitted from the image generating means has a divergence angle equal to or smaller than a predetermined value corresponding to the narrow angle of view of the lens array group, the light diverging at an angle equal to or larger than this angle of view. The component is not projected, and the reproducibility of the image emitted from the image generating means is significantly reduced, particularly in terms of brightness. This collimating optical system 501 is connected to the projection optical system 60.
By arranging it on the side of the first image generating means, it is possible to prevent such deterioration in image quality.

The light beam emitted from the collimating optical system 501 enters the projection optical system 601 after its divergence angle is adjusted. The projection optical system includes first and second lens arrays 602 and 603. Each lens array is configured as an inverted system, and is configured so that the focal length of a set of projection optical systems is erect and equal in magnification. Therefore, when a light beam of an image generated from a place separated by a certain distance enters the projection optical system 601, the image of the emitted light is formed so as to be erected at a point separated by a distance that the generated image is separated. Is configured. In this case, the liquid crystal panel 201
Are arranged so as to form an image on the display screen 801. The lenses constituting the lens arrays 602 and 603 are, for example, spherical surfaces having a diameter of about 0.6 mm, and tens of thousands of lenses are arranged in one lens array. It is not easy to mold and mass-produce such a large number of spherical lenses with high accuracy within a predetermined deviation. Therefore, when molding conditions and design conditions that are easy to mold are found, it is preferable that mass production be performed using only those conditions. With the equal-magnification projection optical system used in the present embodiment, the design conditions of the individual lenses of each lens array can be made substantially the same, and stable production is facilitated.

The light beam emitted from the projection optical system 601 enters a convergence system 701 comprising a Fresnel lens. In this embodiment, a Fresnel lens convergence system 701 is arranged between the lens array group 601 and the display screen 801, so that a light beam incident on the display screen 801 is slightly converged in a direction toward substantially the center of the display screen 801. Let me. In a conventional projection optical system, a diffused light beam or a parallel light beam is projected. Since the light beam emitted from the projection optical system 601 of this embodiment is also a substantially parallel light beam, a component having a high luminance of the light beam is projected almost vertically on the entire display screen. In the case of a display screen of normal quality, even such a system can generate a luminance sufficient to be appreciated. By providing the convergence system 701, a component having a high luminance of the light beam is projected toward the observer 901, so that the peripheral luminance of the image can be further improved. However, if it can be considered that the luminance is obtained to the extent that it can be appreciated, there is no need to arrange this convergence system.

The convergent light emitted from the converging system 701 is
The image is projected on the display screen 801. As the display screen, a screen having a property of dispersing light, such as frosted glass, is used. For this, for example, a light-transmitting plate with a rough surface accuracy can be used, or a thin cylindrical lens arranged in an array can be used.

In addition to such an embodiment, by inserting a second magnifying optical system having a larger optical surface area between the lens array group 601 and the Fresnel lens converging system 701 in FIG. The image in the image generating means can be further enlarged and displayed. In this case, when it is desired to obtain an image having an enlargement ratio that is difficult to realize with one projection optical system, it becomes easy to obtain this with high image quality.

The projection optical system shown in FIG. 3 for further expanding the light beam emitted from the lens array group will be described below. The configuration up to the lens array group 601 is the same as that of the above-described embodiment, and a description thereof will be omitted.

The light beam emitted from the projection optical system 601 enters a magnifying optical system 751 composed of a convex lens. The light beam emitted from the magnifying optical system 751 enters a collimator 752 composed of a Fresnel lens. The convergent light emitted from the collimator 752 is projected on the display screen 801.

In FIG. 3, the magnifying optical system is composed of a single lens. However, if an image is magnified at a time with one lens, the image distortion at the periphery of the light beam greatly increases. For the purpose of correction, the enlargement system may be constituted by a group of lenses to remove aberrations or to enlarge in a stepwise manner. Further, another magnifying optical system for further magnifying the light beam obtained by the magnifying optical system 751 may be provided between the magnifying optical system 751 and the collimator 752. As a result, the design conditions of each magnifying optical system are relaxed, and the manufacturability is improved.

In the above-described embodiment, a light transmission type liquid crystal panel has been described as an example. However, a reflection type display device may be used, and a self light emitting type display device such as an EL panel or a plasma display may be used. Can also be used. Any means for generating an image may be used. For example, an FED (Field Emission Display) may be used instead of the liquid crystal display device. In this case, since it is not necessary to add a light projection optical system, it is possible to further reduce the thickness of the display device. Hereinafter, the FED will be described.

In the FED device shown in FIG. 4, a projection 1001 which is a cathode and emits electrons from the tip is a plate-like gate electrode layer provided with holes 1004 surrounding the tip of the projection 1001, respectively. Cathode device 1 having 1002
000 and a transparent plate 2 made of glass or resin provided so as to face the tip of the projection of the cathode device 1000.
003 includes an anode layer 2001 made of an ITO film and an anode device 2000 having a fluorescent layer 2002 corresponding to the three primary colors on the surface of the anode layer facing the cathode device 1000.

A predetermined number of groups of projections 1001 of the cathode device 1000 shown in FIG. 4 (a) are provided on a single p-layer, which performs an electron emission operation in a lump. Three groups corresponding to each color of R, G, and B are collected into one group
Make up the unit. The protrusion group composed of the p-layer is provided in an island shape on the surface of the n-layer. The gate electrode layer 1002 is provided with an insulating layer 1003 provided over the n-layer or the p-layer. The protrusion 1 is provided on the gate electrode layer 1002.
An opening is provided at a position corresponding to the tip of 001,
The wall surface of this opening is formed so as to surround the tip of the projection 1001.

As shown in FIG. 4B, a large number of projections are arranged at positions corresponding to the pixels on the cathode device 1000, and the projections are controlled by a drive circuit (not shown). The operation of emitting electrons corresponding to the image is performed. Electrons emitted from the projection group advance toward the anode layer 2001 on the simultaneously driven anode device 2000. A fluorescent layer 2002 corresponding to each of R, G, and B is provided on the surface of the anode layer 2001. When the electrons collide with the fluorescent layer and apply energy, the fluorescent layer 2002 emits light. I do. This emitted light is a transparent anode layer 20.
01 and the plate 2003, an image is generated.

As described above, in the display device of the present invention, the brightness of the image may be reduced at the periphery of the display screen. In order to compensate for such a decrease in luminance in the peripheral portion, the FED device serving as an image generating means determines the number of protrusions constituting one pixel corresponding to the peripheral portion of the display screen by changing the number of protrusions corresponding to the central portion of the display screen. The number of protrusions was larger than the number of protrusions. That is, the cathode device 1000 is configured such that the density of the projections constituting the projection group at the peripheral portion of the cathode device is higher than that at the center portion of the cathode device.
Is preferable.

In the above-described embodiment, the magnifying optical system 401 is arranged before the collimating optical system 501. However, a reducing optical system may be arranged. Even if a large-area lens array cannot be formed by placing a reduction optical system,
A high-quality enlarged image can be obtained. This example will be described with reference to the drawings. FIG.
The description of the configuration that is the same as that of the system is simplified.

The optical system of the second display device shown in FIG. 5 includes a light projecting optical system 301, a liquid crystal panel 201, a drive circuit board (not shown) for supplying a drive signal to the liquid crystal panel 201, and a liquid crystal panel 201. A reduction optical system 451 disposed on the side from which an image is emitted, a collimating optical system 501 that collimates convergent light emitted from the reduction optical system, and a collimating optical system 501 that receives light emitted from the collimating optical system 501. A lens array group 601 including the first and second lens arrays 511 and 512, an enlargement optical system 751 that receives and expands light emitted from the lens array group 601 and a collimator 752 that approximately parallelizes the expanded light beam; Display screen 80 that receives light emitted from this collimator 752
1 is provided.

The light emitted from the light projecting optical system 301 passes through the liquid crystal panel 201 to form a light beam constituting a desired image, and this light beam is formed into a reduction optical system 451 comprising a convex lens.
, And the reduced light flux enters a collimating optical system 551 composed of a collimator lens of a concave lens, and is converted into a substantially parallel light flux. The degree of parallelism of the parallel light beam corresponds to the angle of view of the projection optical system 601 at the next stage. The cross-sectional area of the light beam incident on the projection optical system is formed to be smaller than the effective display area of the liquid crystal panel 201 by the reduction optical system 451, and is made substantially parallel by the parallelizing optical system 551. Accordingly, it is possible to use a projection optical system having an area smaller than the effective display area of the liquid crystal panel, and to provide an optical system capable of transmitting more light beams through the projection optical system.

The light beam emitted from the parallelizing optical system 551 enters the projection optical system 601 after its divergence angle is adjusted. The projection optical system includes first and second lens arrays 602 and 603.
It is composed of The focal length of the projection optical system is configured to be equal on both sides. In this case, the liquid crystal panel 201 is arranged so that the image of the liquid crystal panel 201 forms an image on the display screen 801. As described above, the lenses constituting the lens array have a diameter of, for example, about 0.6 mm, and tens of thousands of lenses are arranged in one lens array. It is not easy to mold and mass-produce these lenses with high precision within a predetermined deviation. The larger the area, the more difficult it is to mold. Forming the projection optical system with a small area facilitates the manufacture of the projection optical system. Along with this, the parallelizing optical system 551 can also be formed with a small area. Since the design condition of the collimator becomes stricter as the area becomes larger, there is an advantage that the collimating optical system is easily manufactured as the image is reduced.

The light beam emitted from the projection optical system 601 enters a magnifying optical system 751 composed of a convex lens. The light beam emitted from the magnifying optical system 751 enters a collimator 752 composed of a Fresnel lens. The convergent light emitted from the collimator 752 is projected on the display screen 801.

In FIG. 5, the magnifying optical system is composed of a single lens. However, if an image is magnified by one lens at a time, the image distortion at the periphery of the light beam greatly increases. For the purpose of correction, the enlargement system may be constituted by a group of lenses to remove aberrations or to enlarge in a stepwise manner. Further, another magnifying optical system for further magnifying the light beam obtained by the magnifying optical system 751 may be provided between the magnifying optical system 751 and the collimator 752. As a result, the design conditions of each magnifying optical system are relaxed, and the manufacturability is improved.

Incidentally, in the liquid crystal display device 1 of the above-described embodiment, each optical element can be integrally formed by bonding using another member or other means. As a result, the number of components can be reduced, the optical alignment can be simplified, and the cost of the apparatus can be further reduced.

The above-described lens array group can be replaced by a lens array in which gradient index lenses are arranged in parallel. At this time, the number of components can be reduced, and the need for alignment is eliminated, so that the manufacturability of the magnifying optical system is improved.

Although most of the above-mentioned lenses use ordinary refractive lenses, Fresnel lenses can be used instead. In this case, the thickness of the lens can be reduced, which contributes to the weight reduction of the entire apparatus.
In this case, the Fresnel lens can be constituted by a group of concentric prism zones having no diffraction effect. Since the cross-section is a right-angled triangle and the width of the cross-section is large, the shape is simplified, so that the optical characteristics can be evaluated mainly by using the refraction phenomenon, and there is an advantage that the design and the manufacture are easy. FIG.
FIG. 1 shows a schematic diagram of a local cross section of such a Fresnel lens. With respect to a ridge line a, which is a side substantially parallel to the optical axis O that constitutes the groove shape of the Fresnel lens F shown in FIG. 6, light that exits from this portion, or that is incident on this portion and that is transmitted or reflected, finally passes through the screen. Is a factor that gives distortion to the image projected on the screen. In such a case, there is a technique of removing and flattening the vertex of the Fresnel lens in order to improve the contrast. However, this removes the effective high-speed component, so that the ridge line a is removed from the surrounding optical surface. A rough ground b having a rougher surface than that is formed to scatter incident light, or a light absorbing film such as a black colored paint or a non-reflective multilayer film c is provided. Is preferred. As the roughening treatment, after forming the ridge line a, a plurality of grooves are formed in the optical axis direction by applying the tip of the cutting tool to the ridge line a plural times, or the cutting surface of the cutting edge is roughened. There is a method of forming a plurality of grooves similarly by tracing the ridge line a again with a cutting tool. As a coloring method, there is a coloring method using a dispenser. The predetermined effect can be obtained even if the ridge line a is not uniformly processed for roughening or light absorption.

In this embodiment, a single liquid crystal panel 101 is used. However, it is needless to say that a larger area can be displayed by bonding these liquid crystal panels. With such a large area, there is a concern that the optical surface of the lens array group may be large. Usually, the lens array is formed by injection molding. However, there is a case where it is not easy to increase the area of a single plate due to difficulty in manufacturing a mold. As shown in FIG. 7A, by laminating a plurality of lens array groups, the area of the optical surface of the lens array can be increased. As the adhesive in this case, it is preferable to use an ultraviolet-curable adhesive or the like from the viewpoint that the adhesive is used for bonding related to a process that requires fine adjustment of the position of the bonding surface in a state where the adhesive is attached. .
Also, when the square panels are laminated, the laminated parts are provided in a straight line, and the mechanical strength of the lens array is weakened. Forming these units into a non-regular polygonal shape such as a hook shape or a stepped parallel shape and joining them is effective in reducing the risk of destruction due to an impact load during transport and the bending due to its own weight. FIG.
The lens array shown in (b) shows a state where such non-regular polygonal members are joined together and cut to a required size. The number of joints formed in a straight line is reduced to one. Alternatively, by combining regular hexagons and combining them like a honeycomb, a straight seam over the entire display screen is wiped out. Therefore, it is preferable to increase the area by combining polygonal shapes having an inner angle of 90 degrees or more. At this time, as shown in FIG. 7B, the outer shape may be formed by means such as grinding or cutting after the lens arrays are connected to each other and in accordance with the light image of the housing of the display device.

[0055]

According to the present invention, a projection optical system, an FED, an LCD, a lens array, and a method for manufacturing the same, which can realize a sufficiently enlarged image with a small size and can project a high-quality similar image, are provided. It is possible to provide an improved display device.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a first embodiment of an optical system of a display device of the present invention.

FIG. 2 is a schematic diagram showing an application example of the first embodiment of the optical system of the display device of the present invention.

FIG. 3 is a schematic cross-sectional view of a liquid crystal display device used for the display device of the present invention.

FIG. 4 is a schematic exploded view of the FED used in the display device of the present invention.

FIG. 5 is a schematic diagram showing a second embodiment of the optical system of the display device of the present invention.

FIG. 6 is a schematic sectional view showing an embodiment of the Fresnel lens of the present invention.

FIG. 7 is a schematic diagram showing an example of increasing the area of a lens array.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display device, 201 ... Liquid crystal panel, 301 ... Surface light source part, 401, 751 ... Magnifying lens, 501, 551 ...
Collimator, 601 Projection optical system, 602 First lens array, 603 Second lens array, 701 Converging system, 801 Display screen

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2H052 BA02 BA07 BA14 2H087 KA07 LA01 RA26 RA45 RA47 2H088 EA13 HA08 HA12 HA25 HA27 HA28 MA01 MA20 5G435 AA18 BB05 BB06 BB12 BB17 CC01 DD02 DD06 DD09 FF06 FF08 GG02 GG04 GG02 GG05 GG02 GG05 GG02 GG05

Claims (29)

[Claims] 1. An image generating means having a predetermined effective generating area for generating a light beam corresponding to an image, a display screen having an image display area larger than the effective generating area of the image generating means, and the image An optical system for projecting the image of the generating means on the display screen, wherein at least the optical system is disposed between the image generating means and the display screen, and receives the light flux. A first lens array including a plurality of first lenses and a second lens array including a plurality of second lenses corresponding to the plurality of first lenses. And a projection optical system for projecting the light beam onto a display screen. 2. The display device according to claim 1, wherein the image generating means is a field emission display. 3. A group of projections corresponding to at least pixels at the periphery of the effective generation area of the field emission display has a higher density of projections than a group of projections corresponding to pixels at the center of the effective generation area. 3. The display device according to claim 2, wherein: 4. The display device according to claim 1, wherein the image generating means is of a light transmission type, and a light source is arranged on a side of the image generating means facing the display screen. 5. The display device according to claim 4, wherein the light source includes a diffuse light source unit and a parallel light projecting unit that collimates and projects the light from the diffuse light source unit. 6. The apparatus according to claim 1, wherein at least one enlargement optical system for enlarging an image emitted from the projection optical system is arranged between the projection optical system and the display screen.
The display device according to the above. 7. The display device according to claim 1, wherein an enlargement optical system is disposed between the image generating means and the parallelizing optical system. 8. The display device according to claim 1, wherein a reduction optical system is disposed between the image generating means and the parallelizing optical system. 9. The display device according to claim 1, further comprising a converging system for converging a light beam emitted from the projection optical system on a main surface of the display screen. 10. The display device according to claim 1, wherein the luminance of the light beam emitted from the image generating means is higher near the periphery than at the center of the cross section of the light beam. 11. A collimating optical system that receives a light beam and converts it into substantially parallel light, a first lens array in which a plurality of first lenses are juxtaposed to the collimating optical system, Second lens in which a plurality of second lenses corresponding to the lens
And a lens array for projecting the light beam onto an object to be projected. 12. The projection optical system according to claim 11, wherein the parallelism of the parallel light is a divergence angle within an angle of view of the first lens. 13. A step of receiving an image of an object plane and combining a set of lens arrays capable of projecting an erect image of the image to a position at the same distance from the object plane, and a light beam constituting the image Combining a collimating optical system that emits a light beam having a divergence angle within the angle of view of the lenses constituting the lens array with the pair of lens arrays. Method of manufacturing the system. 14. An image generating means having a higher luminance near the periphery than at the center of the image. 15. A method of manufacturing an image generating means having a step of forming an effective generation area for generating an image, wherein the luminance is adjusted so as to be higher in the vicinity of a peripheral part than in the vicinity of a center part of a surface forming the effective generation area. And forming the effective generation area. 16. The density of the projections corresponding to the pixels at the periphery of the effective generation area of the image is higher than the density of the projections corresponding to the pixels at the center of the effective generation area. A field emission display characterized by: 17. A method for manufacturing a field emission display, comprising a step of combining a cathode device having a projection for emitting electrons with an anode device for attracting electrons emitted from the cathode device to a fluorescent layer, wherein an effective image area is provided. A step of combining a cathode device formed with a higher density of the projections of the projection group corresponding to the peripheral pixel than the projection group corresponding to the pixel at the center of the effective image generation area with the anode layer value. A method for manufacturing a field emission display, comprising: 18. A liquid crystal display device comprising a light source having a luminance of an emitted light beam higher in the vicinity of a cross section of the light beam than in the vicinity of the center thereof. 19. A method for manufacturing a liquid crystal display device having a step of combining a liquid crystal panel and a light source, wherein a light source having a luminance of a light beam emitted is higher in the vicinity of the periphery than in the vicinity of the center of the cross section of the light beam. A method for manufacturing a liquid crystal display device, comprising a step of providing. 20. A lens array in which the optical surfaces of a plurality of lenses are juxtaposed in substantially the same plane, and the optical surfaces of the lens array are integrally formed in juxtaposition in substantially the same plane. 21. A lens array in which optical surfaces of a plurality of lenses are juxtaposed in substantially the same plane and integrally formed, the outer shape of which is a polygonal shape having an inner angle of 90 degrees or more. The lens array according to claim 20. 22. A lens array, comprising a step of forming the optical surfaces of a lens array formed by juxtaposing the optical surfaces of a plurality of lenses in substantially the same plane and further juxtaposing the optical surfaces in substantially the same plane. Manufacturing method. 23. A lens array in which the optical surfaces of a plurality of lenses are juxtaposed in substantially the same plane and integrally formed, the outer shape of which is a polygon having an inner angle of 90 degrees or more. A method for manufacturing a lens array according to claim 22. 24. A Fresnel lens in which a surface substantially parallel to the optical axis direction is formed coarser than other optical surfaces. 25. A Fresnel lens in which a light-absorbing coating is formed on a surface substantially parallel to the optical axis direction. 26. The display device according to claim 1, wherein the optical system includes a Fresnel lens whose surface substantially parallel to the optical axis direction is formed coarser than other optical surfaces. 27. The display device according to claim 1, wherein the optical system includes a Fresnel lens having a light absorbing film formed on a surface substantially parallel to an optical axis direction. 28. An optical system provided in the display device according to claim 1, wherein a surface substantially parallel to an optical axis direction is formed coarser than other optical surfaces. Fresnel lens. 29. A Fresnel lens, wherein an optical system provided in the display device according to claim 1 is configured to be configurable, and a light-absorbing film is formed on a surface substantially parallel to an optical axis direction. .