JP2810572B2 - Projection 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 projection display device for displaying a large screen by combining a plurality of liquid crystal display devices. In recent years, as OA equipment and home electric appliances have become lighter and thinner, in particular, there has been a demand for lighter, thinner, lower power consumption, higher definition, and larger screen sizes of display devices. For this reason, a large screen such as a CRT, a liquid crystal display, a plasma display, an EL display, and an ELD display, and a projection display using a CRT or a liquid crystal have been developed and put into practical use.

When large-screen display is performed by a liquid crystal display device, the yield sharply decreases as the size of the liquid crystal panel increases. Therefore, each display image is continuously formed by a plurality of liquid crystal display devices to form one large image. A method of performing display is conceivable. Therefore, it is necessary to display a seamless high-definition image.

[0003]

2. Description of the Related Art FIG. 27 shows a configuration diagram of a conventional large-screen display. FIG. 27A is a configuration diagram of one liquid crystal display device, and FIG. 27B shows a display screen when four liquid crystal display devices are combined. In the liquid crystal display device 10 shown in FIG. 27A, a printed circuit board 12 is provided around a transmissive liquid crystal panel 11, and the lead pattern 13 is interposed between the liquid crystal panel 11 and the printed circuit boards 12 on three sides. A predetermined number of driver ICs 14 are provided.

FIG. 27B shows a display screen when a large screen is displayed by combining four liquid crystal display devices 10 shown in FIG. 27A, and a display unit corresponding to the liquid crystal panel 11 is shown. 15 and the non-display unit 1 corresponding to the driver IC 14 and the like
There are six. Therefore, the display screen becomes discontinuous as a whole. Therefore, in order to make the discontinuous large display screen continuous, only the image of the display unit 15 of the liquid crystal panel 11 is continuously projected on the screen using an enlargement lens. That is, since the non-display unit 16 is not projected, continuous large-screen display can be performed on the screen.

FIG. 28 is a view for explaining a conventional large-screen display by projection. FIG. 28A shows a liquid crystal display device 10 including a lamp 21, a condenser lens 22, a liquid crystal panel 11, and a projection lens 23.
The display unit 15 (see FIG. 27) of the
To the projector. Combine these three for the sake of explanation.
4 are continuously projected on the screen 4 to display a large screen without any breaks. In this case, partition plates 25 are provided between the liquid crystal display devices 10 to prevent overlapping of images.

Similarly, another method of displaying a continuous large screen on the screen 24 is shown in FIGS. 28 (B) to 28 (D). In FIG. 28B, image matching is performed by irradiating the liquid crystal panel 11 from two point light sources 25 and projecting the liquid crystal panel 11 directly on the screen 24 after being enlarged by divergent light. FIG. 28C shows one point light source 2
The divergent light from 5 is transmitted through the liquid crystal panels 11 and 11 as parallel light by the condenser lens 26a, and enlarged and displayed on the screen 24 by the lenses 26 and 26 to perform image matching.

FIG. 28 (D) shows that the light from the light source 27 is transmitted through the liquid crystal panels 11 and
The light guide bundles 28, 28 corresponding to the pixels 1 and 11 are used to align the screen at the end faces.

[0008]

However, in the case of combining a direct view type as shown in FIG. 27, an attempt has been made to reduce the size of the non-display portion 16, but there is a problem that the non-display portion 16 cannot be completely removed. Further, the projection type as shown in FIG. 28A has a long focal length for forming an imaging system and cannot reduce the depth. FIG.
In (B) and (C), it is necessary to obtain a point light source or a parallel light beam close to an ideal state, and the use efficiency of the light source is poor. And FIG.
(D) has a problem that the cost of the light guide is high.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a projection type display device which performs thin, continuous, high-definition large-screen display.

[0010]

The above-mentioned problems are described below.
This can be solved by taking measures. Claim
Item 1. In the projection display device according to Item 1, the glass substrate
And a predetermined number of pixels are arranged in a matrix.
A transmissive liquid crystal panel, and light is applied to the liquid crystal panel at a predetermined angle.
Irradiation means for irradiating, and pixels with a predetermined number of pixels as one unit
A structure in which a plurality of blocks are formed in one liquid crystal panel;
According to the irradiation angle (θ) from the irradiation means.
Enlarge and form an image for each pixel block and place it on the screen.
Imaging means for projecting seamlessly.
Things.

[0011] According to the invention described in claim 2, the claim
Item 2. In the projection display device according to Item 1, the liquid crystal panel
Forming the image forming means on the one glass substrate
It is characterized by the following. Further, according to the third aspect of the present invention,
In such a projection display device, a light source and a predetermined number of pixels are mated.
Transmission type liquid crystal panels arranged in Rikusu form, the liquid crystal Pas
Upright imaging means for imaging an upright image of a flannel on a screen
And the upright imaging means is provided with a predetermined number of refractive index distributions.
It is characterized by comprising a lens.

[0012]

According to a fourth aspect of the present invention, in the projection type display device according to any one of the first to third aspects, an enlarged projection is performed on a screen by using an enlargement means. Things. According to a fifth aspect of the present invention, in the projection display device according to any one of the first to fourth aspects, an image is projected on the same screen.

According to a sixth aspect of the present invention, in the projection display device according to any one of the first to fifth aspects, of the polarizing plates provided on the entrance surface and the exit surface of the liquid crystal panel, A polarizing plate on an emission surface is provided immediately before the screen. According to a seventh aspect of the present invention, in the projection display apparatus according to any one of the first to fifth aspects, a color filter is provided on a front surface or a rear surface of the screen to perform color display. It is.

According to an eighth aspect of the present invention, in the projection type display device according to any one of the first to third aspects, a light emitting type display device is provided instead of the liquid crystal panel having the light source. It is characterized by the following. According to a ninth aspect of the present invention, in the projection display device according to any one of the fourth to eighth aspects, a Fresnel lens is used as the enlarging means.

[0016]

As a result, the distance from the liquid crystal panel to the image forming means and the distance from the image forming means to the screen can be reduced, and the thickness of the entire apparatus can be reduced. In addition, by combining a plurality of these devices, it is possible to perform uniform, continuous, high-definition large-screen display.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment (A) FIG. 1 shows a block diagram of one embodiment of the embodiment (A) of the present invention. The projection display device 30 shown in FIG.
1, a liquid crystal panel 32, a condenser lens 33 as a condenser means,
It is composed of an imaging lens 34 as an imaging means, a magnifying lens 35 and a screen 36.

FIG. 2 is a diagram for explaining the irradiation means of FIG. In FIG. 2A, the irradiation means 31
Is composed of a light source 31a and a light beam controller 31b. Light beam control unit 31b is obtained by a cylindrical grid-like by arranging cylindrical 31b ₁ of a predetermined number. The light beam control unit 31, as shown in FIG. 2 (B), the light beam from the light source 31a, intended to irradiate within the axial cylindrical 31b ₁ irradiation angle theta, of the cylinder 31b ₁ axis The value of the angle θ can be controlled by the length of the direction.

Returning to FIG. 1, the liquid crystal panel 32 has a liquid crystal sandwiched between two glass substrates 41a and 41b, and a predetermined number of pixels are arranged in a matrix. The drive system is similar to that in FIG. This
The liquid crystal panel 32 has a predetermined number of pixels as one unit.
The configuration is such that a plurality of blocks are formed. A condenser lens 33, there is formed by glass or resin, the light irradiation angle θ for transmitting the pixel blocks 38a of the liquid crystal panel 32 so as to collect light, each pixel block 3
8a is formed integrally.

In this case, the gap 38b (length g) between each pixel block 38a is determined by the irradiation angle θ,
It is within the range of the pixel pitch. Further, the imaging lens 34
Is used to form an inverted image for each pixel block 38a corresponding to the condenser lens 33, and is integrally formed of glass or resin similarly to the condenser lens 33.

Next, FIG. 3 shows a diagram for explaining the projection of FIG. FIG. 3A shows the relationship between the pixel block and the condenser lens, FIG. 3B shows the relationship between the pixel block and the imaging lens, and FIG. 3C shows the relationship between the lens and the magnifying lens. is there. In FIG. 3A, first, each pixel block 38
a is a square of n pixels in length and width, and the length of one side of each pixel block when the pixel pitch is P is nP. If the maximum angle of the light incident on the liquid crystal panel (32) is ± θ, the focal length F ₁ of the condenser lens 33 is F ₁ = (nP + g) / 2 tan θ (1).

When the distance from the pixel block 38a to the condenser lens 33 is S, each pixel block 38a
The length g of the gap 38b is g = 2Stan θ (2). Therefore, after the light transmitted through the pixel blocks 38a is incident on the condenser lens 33, the distance X from the pixel blocks 38a to the virtual image position 39 becomes _{^{X = S 2 / (F 1}} -S) ... (3). That is, the light is emitted from the condenser lens 33 so as to form a virtual image pixel block at the position 39 of the broken line portion behind the pixel block 38a.

All the outgoing light of the condenser lens 33 does not go out of the quadratic prism whose bottom is a square whose nP is one side until the focal point F ₁ . This means that each pixel block 3
This means that the transmitted light 8a does not intersect the transmitted light of the adjacent pixel block at all until the focal point of the condenser lens 33.
Further, in FIG. 3 (B), the between the imaging lens 34 having a focal length F ₂ a condenser lens 33 and its focal point F _1, and from the position 39 of the virtual image pixel blocks of the distance between the imaging lens 34 1 If F ₂ is set to / 2, an inverted 1: 1 image is formed at a position 40 symmetrical to the position 39 of the virtual image pixel block with the image forming lens 34 interposed therebetween.

Further, in FIG. 3C, when the magnifying lens 35 is disposed outside the imaging lens 34, the virtual image position 3
The image No. 9 is formed on the screen 36 with its image forming position and size enlarged. In addition, FIG.
(C) shows only the optical path of the optical system corresponding to one pixel block 38a. However, in practice, the same light beam control is performed by the optical systems corresponding to all the pixel blocks 38a. The pixel block 38a is imaged.

In this case, the enlarged image on the screen 36 is inverted for each pixel block 38a. However, the enlarged image is erected by, for example, providing a memory in the device 30 and changing the arrangement of the display data. be able to. In this way, by forming an image with the imaging lens 34 for each pixel block 38a, the distance between the liquid crystal panel 32 and the imaging lens 34 and the distance from the imaging lens 34 to the screen 36 can be reduced. As a result, the thickness of the entire device 30 can be reduced. Also, these devices 30 are shown in FIG.
As shown in FIG. 3A, a thin, continuous high-definition large-screen display can be performed by combining a plurality.

The condenser lens 33 and the imaging lens 34
May be formed on the glass substrate 37b of the liquid crystal panel 32. As a result, the length of the optical system can be shortened, and
Can be made thinner. Embodiment (B) FIG. 4 shows a configuration diagram of the first embodiment in the embodiment (B) of the present invention. The projection display device 50 shown in FIG.
1, a liquid crystal panel 52, a gradient index lens group 53 as erect image forming means, a magnifying lens 54 as magnifying means, and a screen 55.

In such a projection display device 50, an image (erect image) of the liquid crystal panel 52 is formed at the same magnification at the position 56 a by the refractive index distribution lens group 53. At this stage, the image is enlarged by a magnifying lens 54 and projected on a screen 55. Here, FIG. 5 is a view for explaining the erect image forming means of FIG. In FIG. 5A, the erect image forming means includes a plurality of columnar refractive index distribution lenses 53a arranged in a refractive index distribution lens group 53.
7a is formed as an erect image 57b.

The refractive index distribution lens 53a is formed of a cylindrical glass or plastic resin, and is formed as shown in FIG.
The refractive index changes outward from the center axis of the cylinder using ion exchange or the like as shown in FIG.
Are superimposed on each other to obtain an equal-sized erect image of a plane. That is, the light transmitted through the refractive index distribution lens 53a travels along a locus curved in a sine wave shape. By selecting the distribution rate and the lens length, an erect image 57b of the same size as the incident image 57a is obtained.
Is obtained. As described above, by forming the erect image forming means for obtaining the same-size erect image by the refractive index distribution lens group, the distance required for image formation (that is, the distance from the liquid crystal panel 52 to the image) can be reduced. And the projection display device 50 can be made thinner.

Next, FIG. 6 shows a conceptual diagram of another embodiment of the first embodiment of FIG. FIG. 6A shows a configuration in which a convex magnifying lens 58 serving as a magnifying unit is provided between the refractive index distribution lens group 53 and the incident image 57a (liquid crystal panel). In this case, an erect image of the same size as the enlarged virtual image 57c of the incident image 57a incident on the refractive index distribution lens group 53 is projected on the screen.

Further, the erect image forming means 53 can be constructed by combining two or more convex lenses in place of the refractive index distribution lens. FIG. 6B is an example of this, and an erect image can be obtained by combining two convex lenses 59a and 59b. Also in this configuration, the distance from the liquid crystal panel 52 to the image) can be reduced, and the projection display device 50 can be made thinner.

As described above, by using the erect image forming means 53, an erect image can be obtained with a shorter focal length than that of a conventional imaging lens, and it can be made thinner.
Only the image of the liquid crystal panel 52 can be projected on the screen 55. Next, FIG. 7 shows a configuration diagram of a second embodiment in the embodiment (B) of the present invention. FIG. 7A shows a display device 60 formed by combining four projection display devices 50 shown in FIG. 5 or FIG.
It is shown in (B).

In FIG. 7B, each projection display device 50 has a liquid crystal panel 52 located on a light source 51 (backlight) in a housing 61 and a refractive index distribution lens or a convex lens on the liquid crystal panel 52. And the erect image forming means 53 is located. Further, a plastic Fresnel lens 62 is positioned on the erect image forming means 53 as an enlarging means, and a screen 55 as a display section is disposed in front of the plastic Fresnel lens 62.

Then, only the display image on the liquid crystal panel 52 is enlarged and continuously projected on the screen 55. Here, FIG. 8 shows a configuration diagram of another embodiment of the second embodiment of FIG. FIG. 8 shows a configuration in which the Fresnel lens 62 in FIG. 7 is interposed between the liquid crystal panel 52 and the erecting imaging means 53, and the other configuration is the same as that in FIG.

As described above, by continuously projecting on the screen 55, a thin and continuous large screen can be displayed. In the present embodiment, the projection type display device 50 constituting the display device has a four-unit configuration of two vertical units and two horizontal units. However, in the present method, the number of units and the ratio of the vertical and horizontal units are not particularly limited. The depth of the entire apparatus does not depend on the number of apparatuses.

Embodiment (C) The above-described embodiments (A) and (B) show the case where an image on the liquid crystal panel is formed and projected. The case where light is enlarged and projected is shown. FIG.
FIG. 11 shows a configuration diagram of the first embodiment in the embodiment (C) of the present invention. Projection display device 70 _A in FIG. 9, the surface light source 71
A plate-shaped optical fiber bundle 72 serving as a light beam controlling means is located on the upper side, and a glass substrate 73 similar to that described above is placed on the optical fiber bundle 72.
A liquid crystal panel 73 in which a liquid crystal 73c is sandwiched between a and 73b is located. In addition, a concave lens 74 serving as an enlarging unit is located on the liquid crystal panel 73, and a screen 75 is disposed in front of the concave lens 74.

The projection type display device 70 _A is irradiated with a diffusive (or directional) light beam from the surface light source 71, and converts this light beam into parallel light by the light beam bundle 72. The light is blocked and transmitted by the liquid crystal panel 73,
The image is enlarged by the concave lens 74 and projected on the screen 75. Although the liquid crystal panel 73 is not shown,
A polarizing plate is provided on both surfaces in order to make use of the characteristics.

The concave lens 74 has a function of refracting parallel light rays from below toward the outside from the center of the screen to enlarge an image formed on the liquid crystal panel 73. Screen 7
5 scatters the light beam expanded and refracted toward the outside of the screen,
By returning the light to the diffused light again and emitting it to the front surface, a display with a wide viewing angle is performed. Here, FIG.
FIG. 3 is a diagram for explaining the light beam control means. FIG.
In (A), the light beam control means has a structure in which a large number of glass fibers (which may be transparent resin fibers) 72a are wrapped by a light absorber 72b and bundled into a plate shape. For example, among the light from the lower side in the figure, those that are incident on the respective glass fibers 72a and do not hit the wall of the light absorber 72b are transmitted upward, but those that hit the light absorber 72b are transmitted here. It has a function of being absorbed and not transmitting to the upper side. Therefore, among the diffusive light rays from the light source 71, those that are parallel or nearly parallel to the optical fiber bundle 72 pass, but light rays incident at a certain angle do not pass,
A ray close to a parallel ray is obtained.

Therefore, as shown in FIG. 10B, the diameter: φ, the length: L, and the refractive index: n ₂ of the glass fiber 72a, the refractive index of the surroundings: n ₁ , the incident and outgoing angles: θ ₁ , ray angles in the glass fiber 72a: When _{θ 2, n 1 sin θ 1} = n 2 sin θ 2 ... from _{(4) tan θ 2 = φ} / L ... (5), θ 1 = sin -1 [ _{(n 2 / n 1) (} φ / (L 2 + φ 2) 1/2) ] ... (6) is obtained. Here, if θ ₁ is defined as the parallelism of the light beam, a light beam having a desired parallelism can be obtained by selecting φ, L and n ₂ in the equation (6). Here, it is ideal that θ ₁ is infinitely close to 0, but if the resolution of the image can be tolerated to a level at which there is no practical problem, the distance from the exit surface of the optical fiber bundle 72 to the screen 75 in FIG. Magnification,
An optimum value can be set from the pixel size and the pixel pitch.

Thus, the optical structure is simplified since no imaging system is used. The depth is determined by the distance required for enlarging the image of the liquid crystal panel 73 by the convex lens 74 and the distance at which parallel light rays are formed by the optical fiber bundle 72. The depth is small compared to the focal length of the projection display device, so that the depth is small. , A display device without a frame can be obtained. Next, FIG. 11 shows a configuration diagram of another embodiment of the first embodiment of FIG. Projection display device 70 _A in FIG. 11, the enlarging means those constructed by Fresnel concave 74a, the other is the same as FIG.

Now, in the above equation (6), the refractive index n ₂ of the glass fiber 72a is 1.5, the refractive index n _{1 of} air is 1.0,
10μm diameter φ of the glass fiber 72a, when a 30mm length L, theta ₁ get 0.029 °. Here, the number of pixels is 640 ×
A case is considered in which the length of a liquid crystal display screen having 480 dots and a pixel pitch of 0.33 mm is increased by a factor of 1.3 on the screen 75 so that the frame portion of the liquid crystal panel does not appear. Also, assuming that the distance from the Fresnel concave lens 74a to the screen 75 is 80 mm, the pixel shift caused by the fact that the light beam from the optical fiber bundle 72 is not a perfectly parallel light beam is roughly calculated.

Assuming that the pixel shift is D, D = 80 mm × tan θ ₁ × 1.3 times (θ ₁ = 0.029 °). From (7), D = 0.053 mm, and the pixel pitch after enlargement is 0.43 mm
And the resolution is acceptable even if adjacent pixels are blurred and partially overlap. this is,
This is because the original pixel remains 3/4 even if the adjacent pixels overlap. In this case, the depth is 80 mm for the enlarged portion, 30 mm for the optical fiber bundle, 30 mm for the light source, and 1 mm for the projection screen.
If so, the total is 141 mm, and the display device (see FIG. 15) in which a plurality of display devices are combined is thin.

FIG. 12 is a block diagram of a second embodiment in the embodiment (C) of the present invention. 12 projection display device 70 _B in (A), the optical fiber bundle 72 in place of the lower surface glass of the liquid crystal panel 73 in FIGS. 9 and 11
Are used to form an integrated panel 76, and other configurations are the same as those in FIGS. 9 and 11. In this case, the integrated panel 76
As shown in FIG. 12B, a polarizing plate 76a, an optical fiber bundle 72, a lower electrode 76b, an alignment film 76c ₁ , a liquid crystal 76
d, alignment film 76c ₂ , sealing material 76e, upper electrode 76f,
It is composed of an upper glass plate 76g ₁ and a polarizing plate 76h.

[0043] Such a projection display device 70 _B is diffusible light beam incident on the lower side of the polarizing plate 76a is incident on the liquid crystal 76d is collimated. Lower electrode 76b, alignment film 76c
_{1. Since} the diffusion in the liquid crystal 76d and the polarizing plate 76h is negligible, the parallel light beam directly reaches the concave lens 74 from the liquid crystal panel and is enlarged and projected on the screen 75.

That is, by omitting one glass plate, the thickness can be further reduced. Next, FIG. 13 shows a configuration diagram of another embodiment of the second embodiment of FIG. Projection display device 70 _C in FIG. 13 (A) is a liquid crystal panel shown in FIG. 12 (A) is obtained by an integrated panel 77 by using the optical fiber bundle 72 in place of the top surface glass reverse. In this case, the integrated panel 77 includes a polarizing plate 77a,
Lower glass plate 77b, lower electrode 77c, alignment film 77
d ₁ , liquid crystal 77 e, sealing material 77 f, alignment film 77 d ₂ , upper electrode 77 g, optical fiber bundle 72, and polarizing plate 77 h.

Of the light rays emitted from the lower light source 71 and transmitted through the liquid crystal 77e, only those rays that are almost perpendicular to the surface pass through the optical fiber bundle 72, reach the concave lens 74, are enlarged and projected on the screen 75, and One sheet can be reduced in thickness. Here, FIG. 14 shows a configuration diagram of another embodiment in the embodiment of FIG. FIG. 14 shows the integrated panel 77 of FIG. 13. By making the upper surface shape of the optical fiber bundle 72 into a concave lens shape, parallel rays transmitted through the optical fiber bundle 72 are refracted at the output surface of the optical fiber bundle 72. And
It is a structure that can be spread outward with respect to the center of the screen. In addition,
The exit surface of the optical fiber bundle 72 may form a concave lens with a Fresnel surface.

Next, FIG. 15 shows a configuration diagram of a third embodiment in the embodiment (C) of the present invention. FIG.
_A plurality of projection display devices 70A shown in FIG.
) To display a seamless image on the screen 75. In this case, the housing 78
a, 78b attached to each projection display device 70
_{In A} , vertical and horizontal positioning is performed by the positioning mechanisms 79a and 79b, and the joint of the display on the screen 75 is removed. That is, a thin, high-definition large-screen display can be performed.

Although FIG. 15 shows a combination of two units, a plurality of units may be combined vertically and horizontally in a mosaic pattern. Next, FIG. 16 shows a configuration diagram of a fourth embodiment in the embodiment (C) of the present invention. Projection display device 70 _D of FIG. 16 (A) which was provided with a polarizing plate 77h of the upper surface of the integrated panel 77 onto a screen 75 immediately before in FIG. 13, thereby reducing the influence of irregular reflection at the polarizing plate 77h Is what you do. In this case, the uppermost polarizing plate of the integrated panel 77 is omitted. The polarizing plate 77a and the polarizing plate 7
7h are arranged such that the polarization directions are orthogonal to each other (the liquid crystal 77e is a twisted nematic type). Therefore, FIG.
The invention can be applied not only to the third embodiment but also to the first and second embodiments.

In FIGS. 11 to 16, a color filter for color display may be provided on the liquid crystal panel, and an active element such as a TFT (thin film transistor) may be provided on the electrode 77c. Embodiment (D) FIG. 17 shows a configuration diagram of a first embodiment in an embodiment (D) of the present invention. Projection display device 80 _A in FIG. 17, on the surface light source 81 for irradiating light in the surface direction, the first lenticular lens 82a and the second lenticular lens 82b is the light beam control means is positioned, The liquid crystal panel 83 is located above it. Then, a concave lens 84 which is an enlarging means is located on the liquid crystal panel 83, and a screen 85 is located in front of the concave lens 84.

[0049] Such a projection display device 80 _A, the diffusion resistance than the surface light source 81 is irradiated rays (A-based directional well may), the light rays first and second lenticular lens 82a , 82b as parallel light, the parallel light is blocked and transmitted by a liquid crystal panel 83, and an image of dots is enlarged by a concave lens 84 and projected on a screen 85. The screen 85 scatters the light beam expanded and refracted in the outer direction of the screen, returns the light beam to the diffused light again, and emits the light to the front surface, thereby performing a display with a wide viewing angle.

FIG. 18 is a diagram for explaining the light beam control means of FIG. As shown in FIGS. 18A and 18B, the first and second lenticular lenses 82a and 82b have a structure in which a plurality of cylindrical cylindrical lenses are connected to each other. The light absorbing layer 86a and the light reflecting layer 86b (not formed on the second lenticular lens 82b) are formed on the non-lens side, and are formed with the center of each cylindrical lens. Slit 8 of matching and sufficiently narrow width
6c is formed. First lenticular lens 8
The second lenticular lens 2b and the second lenticular lens 82b are stacked as shown in FIG. 18C so that the respective slits 86c are orthogonal to each other.

The diffusion light source 81 is arranged so that a light beam enters from the slit 82c side of the first lenticular lens 82a. Among the diffused light rays from the light source 81, the light rays that pass through the slits 86c of the first lenticular lens 82a and travel into the transparent resin are refracted in a fan shape with respect to the cross section as shown in FIG. To the lens surface. In this case, the shape of the lens surface is designed such that the light rays from the slit 86c become parallel light rays after refraction on the lens surface. Accordingly, the light passing through the first lenticular lens 82a has its component parallel to the direction perpendicular to the slit 86c of the lens plate. Further, the second lenticular lens 82b placed at right angles to the first lenticular lens 82a further parallelizes the light component in the right angle direction.

More specifically, the thickness of the first and second lenticular lenses 82a and 82b is
If the position of c is the focal point of the lens and the width of the lens is appropriately selected in consideration of the critical angle of the incident light from the slit 86c, the light enters from one slit 86c and the first
In addition, light traveling through the second lenticular lenses 82a and 82b can be prevented from entering the adjacent lens.

When the slit 86c is viewed from the lens surface, if the slit width is sufficiently small, the slit 86c can be regarded as a linear light source, and since the slit 86c is located at the focal point of the lens, it is refracted by the convex lens surface. In the light emitted outside the lens, the component perpendicular to the slit 86c is parallelized.
The condition that the incident light from the adjacent slit does not enter the lens is as follows, assuming that the lens width is L, the minimum thickness of the lens plate is d, the refractive index of the lens plate material is n, and the refractive index of air is 1. It can be expressed by an equation.

D = {L (n ² -1) ^1/2 } / 2 (8) Therefore, in order to obtain perfect parallel rays, it is ideal that the slit width is infinitely small. If the resolution can be tolerated to a level that does not cause a practical problem, an optimum value can be set from the distance from the emission surface of the second lenticular lens 82b to the screen 85, the magnification, the pixel size, and the pixel pitch in FIG. .

Slit width (W _S ) and lens thickness (T _L )
From the relationship, the parallelism (θ ₁ ) due to the slit width not being infinitesimal is calculated. FIG. 18D shows the parallelism (θ ₁ ), the slit width (W _S ), and the lens thickness (T
It is a figure which illustrates the relationship of _L ) simply. The figure is a sectional view taken along a plane perpendicular to the axes of the lenticular lenses 82a and 82b. The lenticular lenses 82a, 82 in this figure
The cross-sectional shape of b is designed so that the light incident on the center of the slit 86c is refracted by the curved surface of the lens and emitted as a parallel light beam. Here, since the slit width is not infinitesimal,
Light incident from a position other than the center of the slit 86c is refracted by the curved surface of the lens and exits the lens obliquely instead of being a parallel ray. In this case, since the incident light from the slit end face deviates most from the direction of the parallel rays, the deviation angle at this time is defined as parallelism (θ ₁ ). Here, the parallelism when the light is incident on the center of the lens is simply calculated. Assuming that the refractive index of the lens material is n and the refractive index of air is 1, from the figure, tan θ ₂ = (W _S / 2) / T _L (9) n · sin θ ₂ = sin θ ₁ (10) from these, parallelism (theta) is, θ ₁ = sin ^-1 _{[n · W S / (4 ·} T L 2 + W S 2) 1/2 ] ... a (11).

Referring back to FIG. 17, this embodiment will be described.
Here, a liquid crystal display screen having a thickness of 14.8 mm, a width of the slit 86c of 10 μm, a refractive index of 1.5, a number of pixels of 640 × 480 dots, and a pixel pitch of 0.33 mm is set for the lenticular lenses 82a and 82b. A case will be considered in which the length dimension is increased 1.3 times on the projection screen so that the frame portion of the liquid crystal panel is apparently lost. Assuming that the distance from the concave lens 84 to the screen 85 is 80 mm, first, the first and second
The pixel shift caused by the fact that the light beams from the lenticular lenses 82a and 82b are not perfectly parallel light beams is estimated.

Assuming that the pixel shift is D, (11)
From equation (7), θ ₁ = sin ⁻¹ [1.5 × 10 μm / (4 × (14.8 mm) ² + (10 μm) ² ) ^1/2 ] = 0.029 ° (12) D = (80 mm + 14) .8 mm) × tan θ ₁ × 1.3 times = 0.062 mm (13) In the above equation, the reason why (80 mm + 14.8 mm) is set is that the light traveling from the first lenticular lens 82a has a longer light ray path by the thickness of the second lenticular lens 82b. Therefore, D =
0.062mm, pixel pitch after enlargement 0.43m
m, which is an acceptable level of resolution even if adjacent pixels are blurred and partially overlap. This is because the original pixel remains close to 3/4 even if the adjacent pixels overlap. In this case, the depth is 80 in the enlarged portion.
mm, lenticular lens section is 14.8 × 2 ≒ 30m
Assuming that m, the light source is 30 mm, and the projection screen is 1 mm, the sum of these is 141 mm. The minimum thickness and lens width of the lenticular lenses 82a and 82b are:
According to the above equation (8), it can be determined in consideration of the lens thickness (T _L ) and the curved surface shape of the lens.

As described above, since the image forming system is not used, the optical structure is simple, and the depth is the distance required for enlarging the image of the liquid crystal panel by the convex lens, the first and the second.
Are determined by the distances at which parallel rays are formed by the lenticular lenses 82a and 82b, but since these are shorter than the focal length of the projection display device, a depth-less display device without a frame can be obtained.

Next, FIG. 19 shows a configuration diagram of a second embodiment in the embodiment (D) of the present invention. Projection display device 80 _B in FIG. 19, between the surface light source 81 in FIG. 17 and the first lenticular lens 82a, in which a light diffusing portion 87 is interposed, the other is the same as FIG. 17 . The light diffusing portion 87 is formed of a uniform high-scattering reflective layer inside, so that the diffused light from the surface light source 81 is more efficiently incident on the first and second lenticular lenses 82a and 82b. belongs to.

Next, FIG. 20 shows a configuration diagram of a third embodiment in the embodiment (D) of the present invention. FIG. 20 corresponds to FIG.
A plurality of projection-type display device 80 _A shown in (2 in the drawing
) To display a seamless image on the screen 85. In this case, the housing 88
a, 88b, each projection display device 80
Vertical and horizontal positioning is performed by the positioning mechanisms 89a and 89b, and the joint of the display on the screen 85 is removed. That is, a thin, high-definition large-screen display can be performed.

Although FIG. 20 shows a combination of two units, a plurality of units may be combined vertically and horizontally in a mosaic form. Embodiment (E) FIG. 21 shows a configuration diagram of the first embodiment in the embodiment (E) of the present invention. In the projection type display device 90 shown in FIG. 21, a liquid crystal panel 92 is located on a parallel light source unit 91 which emits parallel rays as an irradiating unit, and a concave lens 93 which is an enlarging unit is located on the liquid crystal panel 92 and in front thereof. The screen 94 is located.

FIG. 22 is a plan view showing the configuration of the parallel light source shown in FIG. FIG. 23 is a perspective view thereof. In the parallel light source unit 91, a light beam from the light source 95b in the reflecting mirror 95a is turned into a point light source by a pinhole (aperture) 96. The light beam from the point light source is converted into a parallel light beam by a curved Fresnel lens 97 as a light exchange means, and is incident on a first half mirror group 99 via a mirror 98. The parallel light beam reflected by the first half mirror group 99 emits a parallel light beam having a uniform luminance distribution from the entire surface through the second half mirror group 100.

FIG. 24 is a view for explaining the curved Fresnel lens shown in FIG. In FIG. 23A, the curved Fresnel lens 97 has a spherical surface around the point light source 96 on the incident side, and r · sin θ ₁ = L ₀ · on the exit side.
microprism are engraved on a curved surface with a theta ₁ relationship. Further, assuming that the angle intersecting with the center line is θ _{2 as} shown in FIG. 23B, θ ₂ =
∠R−θ ₁ −α, α = sin ⁻¹ [sin θ ₁ / (n ² + 1−
2n · cos θ ₁ ) ^1/2 ].

When such a curved Fresnel lens 97 is used, a light beam radially emitted from a point light source with a uniform luminance distribution is converted into a parallel light beam having a uniform luminance distribution. However, since this parallel light beam is much thinner than the display unit, the first and second half mirror groups 99 and 100 are used. The first and second half mirror groups 99 and 100 have a function of developing a parallel light beam, and include a plurality of half mirrors having different reflectances and transmittances.

The first half mirror group 99 expands in the horizontal direction, and the second half mirror group 100 expands in the vertical direction. Assuming that the width of the light beam is s, (n-1) <(w / s) ≦
It is given by the number n. k-th, k + 1-th (1 ≦ k
If the reflectance and transmittance of the half mirror (<k + 1 ≦ n) are A _k , B _k , A _{k + 1} , and B _{k + 1} , respectively, B _k = A _k /
There is a relationship A _{k + 1} .

As described above, the thin projection type display device 90 can be obtained by the parallel light source section 91. Next, FIG.
FIG. 11 shows a configuration diagram of the second embodiment in the embodiment (E) of the present invention. FIG. 25 shows the projection display device 90 of FIG.
For example, four units are arranged in a matrix, and FIG.
(A) is an overall view thereof, and FIG. 25 (B) is a cross section.

That is, in FIGS. 25A and 25B, four projection display devices 90 are arranged in a matrix in a housing 101, and a screen 102 is provided on the display surface of the housing 101. As shown in FIG. 21, the projection display device 90 includes a parallel light source unit 91, a liquid crystal panel 92, and a concave lens 93.
, And the display screens of the respective devices 90 are arranged so as to have no joint on the screen 102.

Thus, a thin, high-definition large-screen display can be performed. Although FIG. 25 shows the case of four units, the present invention is not limited to this, and any number of units arranged in a matrix may be used. In the above embodiment (B),
Although a liquid crystal panel is used as the display device, a light-emitting display device such as a CRT or a plasma display may be used if the display portion is flat.

Embodiment (F) FIG. 26 is a block diagram showing one embodiment of the embodiment (F) of the present invention. FIG. 26A is a diagram for explaining the configuration of the embodiment. In this embodiment, a light beam irradiating unit 112 that irradiates a liquid crystal panel 111 with a light beam and light beams from the light beam irradiating unit 112 are red (R) and green. (G), a liquid crystal panel 111 of black and white display for blocking / transmitting light rays corresponding to the pixels of blue (B), and a magnifying lens having a function of enlarging and forming light rays emitted from the liquid crystal panel 111 on a screen 113. A color filter 115 for selectively transmitting only the three primary colors of R, G, and B by associating light rays from the image section 114 with the pixels with the pixels, and a screen 113 for diffusing the light rays from the color filter 115 to form a color display. It is composed of planes. FIG.
(B) shows an example of the structure of the screen of the present embodiment. The screen 113 has a transparent resin plate 121 of acrylic or the like as a substrate, on which color filters 115 of each color of RGB are formed in a mosaic or stripe shape, and a black matrix is formed thereon so as to cover a boundary between pixels of each color. The light diffusion layer 116 is formed on the color filter 115 and the black matrix 115a. Color filter 115
Can be formed by printing, dyeing, or face immersion, and the black matrix 115a is formed by printing a black paint or the like. The light diffusion layer 116 can be formed by stacking a diffusion material or the like. Each color filter 115
Is calculated and designed based on the size of each pixel of the liquid crystal panel 111 and the enlargement ratio of the enlarged image forming unit. Each pixel of the liquid crystal panel 111 and a pixel of the color filter 115 of the screen 113 are aligned and assembled so as to correspond to each other in image formation. According to the present embodiment, by disposing the color filter 115 close to the imaging plane, when the color filter 115 is provided in the liquid crystal panel 111, the enlarged imaging unit 114 due to the scattering of light rays by the color filter 115. Generation of extraordinary light can be prevented. Further, the light diffusion layer 1 includes a black matrix 115a that plays a role of blocking light leaking between pixels of the color filter 115.
16, the influence of external light entering the screen 113 from above can be reduced.

[0070]

As described above, according to the present invention, an image of a flat display such as a transmissive liquid crystal panel is formed by an image forming means having a short focal length, or enlarged and projected by a parallel light beam. A thin, high-definition large-screen display can be performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment (A) of the present invention.

FIG. 2 is a diagram for explaining an irradiation unit in FIG. 1;

FIG. 3 is a diagram for explaining the projection of FIG. 1;

FIG. 4 is a configuration diagram of a first embodiment in an embodiment (B) of the present invention.

FIG. 5 is a view for explaining the erect image forming means of FIG. 4;

FIG. 6 is a conceptual diagram of the first embodiment in the first embodiment of FIG. 4;

FIG. 7 is a configuration diagram of a second embodiment in the embodiment (B) of the present invention.

FIG. 8 is a configuration diagram of another embodiment of the second embodiment of FIG. 7;

FIG. 9 is a configuration diagram of a first embodiment in the embodiment (C) of the present invention.

FIG. 10 is a diagram for explaining the light beam control means of FIG. 9;

FIG. 11 is a configuration diagram of another embodiment of the first embodiment of FIG. 9;

FIG. 12 is a configuration diagram of a second embodiment in the embodiment (C) of the present invention.

FIG. 13 is a configuration diagram of another embodiment of the second embodiment of FIG. 12;

FIG. 14 is a configuration diagram of another embodiment of the embodiment of FIG.

FIG. 15 is a configuration diagram of a third embodiment in the embodiment (C) of the present invention.

FIG. 16 is a configuration diagram of a fourth embodiment in the embodiment (C) of the present invention.

FIG. 17 is a configuration diagram of the first embodiment in the embodiment (D) of the present invention.

FIG. 18 is a diagram for explaining the light beam control means of FIG. 17;

FIG. 19 is a configuration diagram of a second embodiment in the embodiment (D) of the present invention.

FIG. 20 is a configuration diagram of a third embodiment in the embodiment (D) of the present invention.

FIG. 21 is a configuration diagram of a first embodiment in an embodiment (E) of the present invention.

FIG. 22 is a configuration diagram of a parallel light source unit in FIG. 21;

FIG. 23 is a view for explaining emitted light in FIG. 22;

FIG. 24 is a view for explaining the curved Fresnel lens of FIG. 22;

FIG. 25 is a configuration diagram of a second embodiment in the embodiment (E) of the present invention.

FIG. 26 is a configuration diagram of one embodiment in Embodiment (F) of the present invention.

FIG. 27 is a configuration diagram of a conventional large-screen display.

FIG. 28 is a diagram for describing a conventional large-screen display by projection.

[Explanation of symbols]

 Reference Signs List 30 Projection display device 31 Irradiation means 31a Light source 31b Light beam control unit 32 Liquid crystal panel 33 Condensing lens 34 Imaging lens 35 Magnifying lens 36 Screen 38a Image block 38b Gap

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-53510 (JP, A) JP-A-60-227233 (JP, A) JP-A-3-107102 (JP, A) JP-A-3-107102 228024 (JP, A) JP-A-2-149837 (JP, A) JP-A-62-299943 (JP, A) JP-A-2-39210 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G02F 1/13 G02F 1/1335 G03B 21/00

Claims (9)

(57) [Claims] 1. A transmission type liquid crystal panel sandwiched between glass substrates and having a predetermined number of pixels arranged in a matrix, irradiating means for irradiating the liquid crystal panel with light at a predetermined angle, A plurality of pixel blocks as a unit are formed in one liquid crystal panel, and an enlarged image is formed for each of the pixel blocks according to an irradiation angle (θ) from the irradiation unit, and the image is formed on a screen. A projection type display device, comprising: imaging means for projecting seamlessly. 2. The projection display device according to claim 1, wherein said imaging means is formed on said one glass substrate of said liquid crystal panel. 3. A light source, a transmissive liquid crystal panel in which a predetermined number of pixels are arranged in a matrix, and erect image forming means for forming an erect image of the liquid crystal panel on a screen. 2. The projection display device according to claim 1, wherein said erect image forming means is constituted by a predetermined number of gradient index lenses. 4. The method according to claim 1, wherein
In a projection display device, using an enlargement unit to enlarge an image on a screen.
Characteristic projection display device. 5. The method according to claim 1, wherein
In a projection display device, an image is projected on the same screen.
Photographic display device. 6. The method according to claim 1, wherein
In a projection display device, a polarizing plate provided on an entrance surface and an exit surface of the liquid crystal panel
Of which, the polarizing plate on the exit surface is provided immediately before the screen.
A projection display device characterized by the above-mentioned. 7. The method according to claim 1, wherein
In a projection display device, color filters are provided on the front or
-A projection display device for performing display. 8. The method according to claim 1, wherein
In the projection display device, a light-emitting display is used instead of the liquid crystal panel having the light source.
A projection display device provided with a device. 9. The method according to claim 4, wherein
In the projection display device, a Fresnel lens is used as the enlargement unit.
Projection type display device.