JP3178313B2 - 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 display device for enlarging and displaying an image formed by image light from an image generator, and to greatly reduce the thickness of the display device.

[0002]

2. Description of the Related Art As a display device, there is a display device that displays an image using an image generator that emits image light. Image generators used in this type of display device include a liquid crystal display panel,
There are an electroluminescence display panel, a plasma display device, a cathode ray tube (CRT), and the like. As the liquid crystal display panel, a TFT (thin film transistor) that can be driven in a high time division and can display a high-definition image is generally used. An active matrix type liquid crystal display panel as an element is used.

[0003] Recently, the above-mentioned display device has a tendency to have a large screen, and as a means thereof, it has been considered to enlarge the image generator itself or adopt a projection method.

In the above-mentioned projection system, image light from an image generator is enlarged by a projection lens system and projected onto a screen surface. This projection type display device has an image generation device inside a device main body having a display window. Place the body and the projection lens system,
The transmission window is provided with a transmission screen.

[0005]

However, the enlargement of the screen size of the image generator causes a problem that the production yield of the image generator decreases and the cost increases. For example, in an active matrix type liquid crystal display panel using a TFT as an active element, a gate line and a data line for supplying a gate signal and a data signal to the TFT become longer with an increase in screen size. The occurrence rate of short-circuits between them becomes high, and the production yield is greatly reduced.

Moreover, in order to increase the screen size of the liquid crystal display panel, a pair of transparent substrates facing each other with a liquid crystal layer interposed therebetween must have a large area.
Since it is necessary to use an expensive glass substrate having high heat resistance for the substrate on which the FT is formed, the enlargement of the screen of the liquid crystal display panel, together with the decrease in the manufacturing yield, results in an increase in cost. Become.

On the other hand, in the above-mentioned projection type display device, the image generator to be used may be of a small screen which can be obtained with good yield and at low cost, but a projection lens system is arranged on the emission side of the image generator. Since the screen is arranged in front of the projection lens system with a projection optical path length that provides a desired magnification, it is difficult to reduce the depth dimension of the device and make it thinner.

Moreover, in this display device, it is difficult to completely eliminate the lens aberration in the projection lens system, so that there is a problem that the projected image on the screen is distorted to some extent.

Furthermore, in this display device, the projection lens system is very expensive, and focus adjustment means and the like of the projection lens system are required, and the alignment of the optical axis of the projection lens system is difficult, and it is troublesome to assemble. Therefore, the price of the apparatus is considerably increased.

According to the present invention, a large-screen image can be obtained by using a small-screen image generator which can be obtained with good yield and at low cost. In addition, the depth dimension of the apparatus can be reduced to reduce the thickness. It is an object of the present invention to provide a display device which can obtain a high-quality enlarged image without distortion, and has a very simple structure and can be manufactured at low cost.

[0011]

A display device according to the present invention comprises:
An image generator that emits image light, an incident surface that captures image light from the image generator almost perpendicularly, and a plurality of surfaces that are substantially perpendicular to the light guide direction are formed in a step-like shape. light
A light guide having an emission surface inclined with respect to a direction, and a prism portion formation surface on which a plurality of prism portions are formed, and the prism portion formation surface forms an emission surface of the light guide. The image light emitted from the light guide is refracted in a direction substantially perpendicular to the light exit surface of the light guide, is divided into a plurality of light beams corresponding to the plurality of prism portions, and is enlarged along the inclination direction of the light exit surface of the light guide. An image forming unit that emits the image light, and a light diffusing unit that receives the image light emitted from the image forming unit, diffuses the image light, and emits the image light. The displayed image is enlarged and displayed in one side direction.

In this display device, the image light from the image generator is taken almost perpendicularly to the light guide and emitted from the emission surface. The light exit surface of the light guide is a surface formed in an inclined shape, and the image light from the light exit surface is emitted by the image forming means while being enlarged along the inclination direction. When observing the emitted light, an image obtained by enlarging an image formed by the image light from the image generator in one side direction can be seen.

Therefore, according to this display device, a large-screen image can be obtained by using a small-screen image generator that can be obtained with good yield and at low cost. Moreover, according to this display device, the image light emitted from the emission surface of the light guide is enlarged and emitted along the tilt direction by the image forming means, so that the image light of the image generator is projected from the projection lens system. Compared to a conventional projection display device that projects onto a screen placed at a position separated by the optical path length, the thickness can be significantly reduced.

Further, in this display device, the image light from the image generator is taken into the light guide substantially perpendicularly from the incident surface thereof, and reaches the emission surface of the light guide without diffusing to the surroundings. The enlarged image is a high-quality image without distortion.

Further, this display device has a simple structure in which the light guide is arranged on the emission side of the image generator, and the light guide is provided only with its incident surface opposed to the image generator. For this reason, it can be manufactured at extremely low cost as compared with a conventional projection type display device which requires an expensive projection lens system and requires accurate alignment thereof.

In the display device according to the present invention, it is desirable that the light emitting surface of the light guide is formed in a stepped manner, so that the light guided through the light guide is formed in a stepped manner. Since the light is emitted at high emission rates from the surfaces, that is, the plurality of surfaces substantially perpendicular to the light guide direction of the light guide, the image light guided by the light guide can be efficiently emitted.

Preferably, the image forming means is configured to refract image light emitted from the light exit surface of the light guide in a direction substantially perpendicular to the light exit surface and emit the light. If the means is adopted, the image light emitted from the emission surface of the light guide can be efficiently expanded and emitted along the inclined direction.

Further, in this display device, light diffusion means is provided on the emission surface side of the image forming means .
I, it is possible to widen the viewing angle, also by providing the parallel beam generating means for emitting a light guide in the parallel light image light from the image generator, most of the image light from the image generator To the light guide to improve the light efficiency.

In this case, when the image generator converts the light from the light source into image light and emits the image light, the parallel light generating means may be provided in the light source section. When it generates image light itself, the parallel light generating means may be provided between the image generator and the light guide.

The light guide may be formed by densely forming a large number of light guide paths made of, for example, resin.
Liquid crystal display panel, electroluminescence display panel,
Any of a plasma display device, a cathode ray tube, and a laser display device may be used.

Further, in the display device according to the present invention, the image forming means may be configured to refract image light emitted from the light emitting surface of the light guide in a direction substantially perpendicular to the light emitting surface and emit the light. Desirably, if such an image forming means is employed, the image light emitted from the emission surface of the light guide can be efficiently expanded and emitted along the inclined direction.

In the case where the light emitting surface of the light guide is formed in a stepped shape, the light emitting surface may be formed by cutting the light guide in a stepped shape, or by cutting the light guide in a straight line. A sloped surface may be formed, and the back surface of a member having a stepped surface formed on the sloped surface may be in close contact with the inclined surface. According to the latter, a stepped emission surface can be easily formed. .

Further, another display device according to the present invention includes an image generator for emitting image light, an incident surface for capturing image light from the image generator substantially perpendicularly, and a light guide direction.
It has a plurality of perpendicular surfaces and is formed in a step shape, and in the light guide direction
A first light guide having an emission surface inclined with respect to the first light guide, and a prism portion forming surface on which a plurality of prism portions are formed
Image light emitted from the emission surface of the first light guide is incident on the prism portion forming surface , and the incident image is
The light is bent in a direction substantially orthogonal to the exit surface of the first light guide.
A first image forming unit that folds, expands and emits along the direction of inclination of the exit surface, and an entrance surface that comes into contact with the first image forming unit and captures image light emitted from the exit surface. , Has a plurality of planes substantially perpendicular to the light guide direction
A second light guide having a light emitting surface formed obliquely with respect to the light guide direction, and a plurality of prism portions.
Having a prism part forming surface formed, wherein the prism part forming surface
The image light emitted from the emission surface of the second light guide is
And the incident image light exits the second light guide.
A second image forming means which refracts in a direction substantially perpendicular to the emitting surface and expands and emits the light along an inclined direction of the emitting surface ;
The image light emitted from the image forming means is incident, and
A light diffusing means for diffusing and emitting image light , wherein an image formed by the image light from the image generator is enlarged and displayed.

According to this display device, the image light from the image generator is emitted from the first image forming means via the first light guide to become image light enlarged in one side direction,
Since the image light is emitted from the second image forming means via the second light guide and becomes image light enlarged in the other side direction, the image formed by the image light from the image generator can be formed. An enlarged image enlarged in one side direction and the other side direction can be obtained.

Further, another display device of the present invention comprises a plurality of image generators for emitting image light, an incident surface for taking the image light from each of the image generators substantially vertically, and a light guide direction.
It is formed in a step shape with a plurality of surfaces substantially perpendicular to the
Double having an exit surface formed in an inclined shape with respect to the light guide direction
A plurality of image generating means comprising a number of light guide, the plurality of image generating means disposed side edges of the exit surface of each of the light guide close contact so together, the exit surface of each light guide Inclination
Combined image generation means with aligned directions and multiple prism units
A prism portion forming surface formed on the prism portion;
The surface refracts the composite image light emitted from the composite image generating means in a direction substantially orthogonal to the emission surface of each of the light guides.
And a plurality of prisms corresponding to the plurality of prisms.
An image forming edge that splits and expands along the direction of inclination of the light emitting surface of each light guide, and emits light from the image forming unit.
Image light is incident, diffuses and emits the image light
Light diffusing means for displaying a plurality of images integrally.

According to this display device, the plurality of images obtained by enlarging the images formed by the image light from the plurality of image generators in the direction of one side are displayed as integral enlarged images connected to each other at the side edges. Can be.

[0027]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 10 show a first embodiment of the present invention.
FIG. 1 is a side view of a display device. The display device of this embodiment uses a liquid crystal display panel that converts light from a light source into image light and emits the light, as an image generator that emits image light.
A light source unit 20 disposed behind the liquid crystal display panel 10, a light guide 30 disposed on an emission side of the liquid crystal display panel 10, and a light guide unit 30 disposed close to an emission surface of the light guide 30. Image forming means 40 and a light diffusing means 50 provided on the emission surface side of the image forming means 40.

The liquid crystal display panel 10 is of a TN (twisted nematic) type and has a liquid crystal cell 11
And a pair of polarizing plates 17 and 18 arranged on the incident surface side and the emission surface side of the liquid crystal cell 11.

Although the detailed structure of the liquid crystal cell 11 is not shown, a nematic liquid crystal is formed in a display area surrounded by the sealing material on a pair of transparent substrates joined via a frame-shaped sealing material surrounding the display area. , And transparent electrodes are provided on the inner surfaces of both substrates, respectively.

The liquid crystal display panel 10 used in this embodiment is an active matrix type color liquid crystal display panel using a TFT (thin film transistor) as an active element. Are provided on the inner surface of the other substrate, and a single-film counter electrode facing all the pixel electrodes of the one substrate is provided. And multiple colors, for example, red, green, blue
Color filters of colors are provided alternately.

FIG. 10 shows one substrate 1 of the liquid crystal cell 11.
2 is a diagram showing, in an equivalent circuit, pixel electrodes, TFTs, and the like provided in a pixel electrode 2. The pixel electrodes 13 are arranged side by side in a row direction and a column direction, and a TFT 14 is provided corresponding to each of the pixel electrodes 13. ing. Also, this substrate 1
2, TFTs of each row are wired for each pixel electrode row.
A gate line 15 for supplying a gate signal to 14 and a data line 16 wired for each pixel electrode column and supplying a data signal to the TFT 13 in each column are provided.

Further, an alignment film is provided on the inner surfaces of the pair of substrates so as to cover the electrodes, respectively. The orientation of liquid crystal molecules in the vicinity of each substrate is regulated by the alignment film. The substrates are twist-oriented at a predetermined twist angle (for example, approximately 90 °) between the substrates.

The liquid crystal display panel 10 has the same number of pixels as a normal high-definition liquid crystal display panel. However, the display image of the normal liquid crystal display panel is compressed in the vertical direction of the screen.
A horizontally long image having an outer shape as shown in FIG. 9A is displayed.

That is, the liquid crystal display panel 10 has a narrow rectangular shape in which the dimension in the width direction is a fraction of the dimension in the length direction (the direction perpendicular to the paper surface in FIG. 1). As shown in FIG. 10, each of the pixel electrodes 13 of the liquid crystal cell 11 has a vertical width (a vertical width of the screen) and a vertical / horizontal ratio. In addition to the horizontal electrodes which are reduced to a fraction of the pixel electrodes of the display panel, the arrangement pitch of the pixel electrodes 13 arranged in the vertical direction of the screen is reduced to display a horizontal image compressed in the vertical direction of the screen. Things.

Further, the light source unit 20 converts the image light from the liquid crystal display panel 10 provided on the emission side of the backlight unit 21 and the liquid crystal display panel 10 into parallel light and emits the parallel light to the light guide 30. And a parallel light generating means 25 for performing the operation.

The backlight unit 21 is disposed along a light guide plate 22 made of acrylic resin or the like having a size opposed to the entire display area of the liquid crystal display panel 10, and along one end surface of the light guide plate 22. It comprises a straight tube light source lamp (fluorescent lamp) 23 and a reflector 24 for reflecting light from the light source lamp 23 toward the end face of the light guide plate 22. Light from the light source lamp 23 is The light enters the light guide plate 22 from one end face thereof, is guided inside the light guide plate 22, is reflected by the back face, and is emitted from the entire front face.

The parallel light generating means 25 converts the light emitted from the light guide plate 22 into parallel light,
0, and the parallel light generating means 25
Although a detailed structure thereof is not shown, for example, a light refractor that refracts light emitted from the light guide plate 22 upward,
The light refractor is constituted by a microlens array (a large number of linear lenses having a fine width are arranged in parallel) that emit light as parallel light perpendicular to the incident surface of the liquid crystal display panel 10. ing.

The parallel light generated by the parallel light generating means 25 passes through the liquid crystal display panel 10 to become image light, and is emitted from the liquid crystal display panel 10 to the light guide 30.

The light guide 30 is connected to the liquid crystal display panel 1.
The light guide 30 has a configuration in which a large number of resin-made linear light guide paths 31 for guiding light in a direction substantially perpendicular to the emission surface of the light guide 30 are provided. The light guide direction matches the light guide direction of the light guide path 31.

The light guide 30 has an incident surface 30a formed perpendicular to the light guide direction and for taking in the image light from the liquid crystal display panel 10 almost perpendicularly, and an inclined surface with respect to the light guide direction. The light exit surface 30b is formed, and the area of the incident surface 30a (the same area as the cross-sectional area perpendicular to the light guide direction of the light guide 30) corresponds to the light generated by the liquid crystal display panel 10. The size of the image, that is, the liquid crystal display panel 10
Is equal to or slightly larger than the area of the display area.

The light exit surface 30b is formed by cutting out the light guide 30 in a stepwise manner, and the light that is taken in from the incident surface 30a and travels through each light guide path 31 is a stepped surface, that is, a light guide. The light exits from a plane substantially perpendicular to the light guide direction of the light body 30. The inclination angle (the inclination angle with respect to the light guide direction) θ of this stepped surface is set in accordance with an image enlargement ratio described later.

The light guide 30 has a diameter of 20 to 50 μm.
An optical fiber assembly obtained by densely integrating a large number of ultrafine optical fibers into a single piece is cut into a predetermined size, and the light guide path 31 is formed of a core (core wire) of the optical fiber.

FIG. 2A shows the optical fiber. The optical fiber 32 is formed by bending the peripheral surface of an acrylic resin core 32a having a diameter of 10 to 30 μm made of a thermoplastic resin such as a fluoropolymer. Clad material 32b with different rates
With a thickness of 5 to 10 μm.

The light guide 30 is formed by densely arranging about 1500 to 2500 optical fibers 32 in a bundle to form an optical fiber collecting rod 33 having a diameter of 6 to 10 mm as shown in FIG. A large number of the optical fiber assembly rods 33 are densely packed and heated in a mold, so that the cores 32a of the optical fibers 32 are joined together by a cladding material 32b to form an integrated optical fiber assembly 35 (see FIG. 4). Is manufactured by a method of cutting the optical fiber assembly 35 into a predetermined size.

The optical fiber collecting rod 33 is
After the core 32a is formed by extrusion molding,
A bundle of about 500 cores 32a can be formed by passing the bundle of the clad material through a bath in which the clad material is melted and solidifying the adhered clad material. In this case, the optical fibers 32 are densely packed one by one. Optical fiber collecting rod 33
It saves time and is more efficient than creating

The optical fiber assembly 35 is similar to that shown in FIG.
As shown in the figure, the optical fiber assembling rod 33 is packed without gaps into a rectangular cylindrical mold 34 manufactured according to the outer peripheral shape of the optical fiber assembly to be manufactured, and in that state, the melting temperature of the clad material 32b is reduced. The optical fiber 32 is manufactured by heating so that the optical fibers 32 are joined together by the cladding material 32b.

As described above, when the clad material 32b of each optical fiber 32 is melted by heating in a state where the optical fiber collecting rods 33 are packed in the mold 34 without any gap, the volume of the clad material 32b expands, and The mold pressure increases, and the pressure causes the cores 32a of the optical fibers 32, which were randomly densely packed in the state of the optical fiber collecting rod 33, to have the highest density for each optical fiber collecting rod 33. Since the clad material 32b is hardened by gradual cooling in this state because it is arranged in a dense, so-called close-packed state, the optical fiber aggregate 3 shown in FIG.
5 is obtained.

FIG. 5 is an enlarged sectional view of one optical fiber collecting rod 33 of the optical fiber assembly 35 manufactured as described above. Since the cores 32a are arranged in a dense state having the highest density as described above, they have a regular hexagonal column shape.

That is, the optical fiber assembly 35 is
Each of the optical fibers 32 has a structure in which regular hexagonal prism-shaped optical fiber collecting rods 33 in which the cores 32a of the optical fibers 32 are arranged in a dense state having the highest density are connected to each other.

Then, the light guide 30 cuts the optical fiber assembly 35 to a predetermined length,
(A), as shown in (a), it is cut obliquely along a cutting plane C connecting one side edge of one end face and the other side edge of the other end face to obtain a block having a right side triangular shape. The oblique cut surface of the block is cut out stepwise as shown in FIG.

In the manufacture of the light guide 30, the optical fiber assembly rod 33 can be easily formed simply by packing the optical fiber 32 in a mold and heating as described above. 35 can also be easily manufactured simply by packing the optical fiber collecting rod 33 in the mold 34 and heating. Further, the optical fiber assembly 35 cut to a predetermined length is cut obliquely along the cut surface C shown in FIG. Since the block can be obtained, no material is wasted, and notch processing for forming the diagonal cut surface of the block in a stepwise manner can be easily performed by the existing precision cutting device. Therefore, the light guide 30 can be manufactured efficiently and at low cost.

The light guide 30 thus manufactured is
The incident surface 30a is a surface that is substantially perpendicular to the light guide direction of the light guide 30, and the exit surface 30b is a surface formed in a step-like shape. The inclined surfaces (surfaces shown by two-dot chain lines in the figure) formed by joining are formed to have the same width and the same step so that they become one plane.

It is desirable that the width of each step surface (a surface substantially perpendicular to the light guide direction) of the exit surface 30b be as small as possible. (Determined by the inclination angle θ of the stepped surface with respect to the light direction and the width of each stepped surface).

In this embodiment, each step surface of the exit surface 30b is formed to have a very small width (about 0.05 to 0.5 mm) such that several to several tens of light guide paths 31 exist within the width thereof. ). In this embodiment, the inclination angle θ of the stepped surface with respect to the light guide direction of the light guide 30 is selected to be 11.5 ° to 30 °, and the width of the stepped emission surface 30b in the vertical direction is set to the incidence surface 30a 5 to 2 times the width of the pixel electrode 13 of the liquid crystal display panel 10, and the vertical width thereof is 1/5 to 1/5 of the pixel electrode of the liquid crystal display panel for displaying an image having a normal vertical / horizontal ratio. It is a horizontally long electrode which is 1/2.

The light guide 30 has a stepped emission surface 30b formed by cutting the light guide in a stepwise manner. The light guide 30 has a structure as shown in FIG. It may be.

In the light guide 30 shown in FIG. 7, the back surface of the sheet member 36 having a stepped surface is brought into close contact with an inclined surface formed by cutting the stepped emission surface 30b linearly. The sheet member 36 is made of a resin having the same refractive index as the light guide path (the core 32a of the optical fiber 32) (for example, the same acrylic resin as the light guide path 31).
Or made of a resin having a refractive index close to that of the light guide path 31.

The light guide 30 cuts the above-mentioned optical fiber aggregate 35 obliquely along the cut surface C shown in FIG. 6A, and then attaches the sheet member 36 to the oblique cut surface.
And the sheet member 36 can be molded using a molding die. Therefore, the width of each step surface is cut out of the light guide in a stepwise manner. It can be even smaller than in the case.

The light guide 30 has an incident surface 3
The liquid crystal display panel 10 is disposed so as to be parallel and close to the light exit surface of the liquid crystal display panel 10, or the light incident surface 30a is in contact with the light exit surface of the liquid crystal display panel 10.

On the other hand, the image forming means 40 arranged close to the light exit surface of the light guide 30 converts the light emitted from the light guide 30 to the inclination direction of the light exit surface 30b of the light guide 30. The light is refracted in a direction substantially perpendicular to the image forming means. The image forming means 40 includes, for example, a prism sheet 41 as shown in FIG. This prism sheet 41 is
The light guide 30 is made of a resin (for example, polycarbonate) sheet having substantially the same size as the slope along the stepped emission surface 30b, and a large number of horizontally long prism portions 42 are formed on one entire surface of the light guide 30 by about 50 μm. Are formed in parallel with each other at an extremely small pitch.

The prism sheet 41 is arranged such that its prism portion forming surface is in close proximity to the stepped emission surface 30b of the light guide 30, or is in contact with the stepped emission surface 30b, and The stepped emission surface 30 is set so that the length direction of each prism portion 42 is parallel to the length direction (left-right direction) of the stepped emission surface 30b of the light guide 30.
It is arranged to be inclined parallel to the slope along b.

Further, the light diffusing means 50 provided on the emission surface side of the image forming means 40 is, for example, provided on one surface of a resin sheet having substantially the same size as the prism sheet 41 as the image forming means 40. And a light diffusion sheet in which a very large number of minute lens portions are formed at close intervals. The light diffusion sheet 50 is opposed to the prism sheet 41 in parallel or close to the prism sheet 41, or Are arranged so as to be in contact with each other.

In the display device of this embodiment, the parallel light from the light source unit 20 is incident on the liquid crystal display panel 10, and the light emitted from the liquid crystal display panel 10, that is, the liquid crystal display panel 10
Is guided by the light guide 30 and emitted from the emission surface 30b of the light guide 30, and the image light emitted from the emission surface 30b of the light guide 30 is Image forming means 4 composed of prism sheet 41
The image formed by the image light from the liquid crystal display panel 10 is enlarged and displayed in one side direction by expanding and emitting the light along the inclination direction by 0.

That is, in this display device, the light emitted from the liquid crystal display panel 10 diffuses through the plurality of light guide paths 31 constituting the light guide 30 to the periphery while repeating refraction in the light guide paths 31. The light is guided along the light guide direction without exiting, and exits from the exit surface 30 b of the light guide 30.

The size of one pixel of the liquid crystal display panel 10 (the size of the pixel electrode 13) is, for example, about 100 μm in horizontal width (width of the screen in the horizontal direction) and vertical width (width in the vertical direction of the screen). ) Is １ ／ to の of the width a 1, whereas the diameter of the light guide path 31 of the light guide 30 (the diameter of the core 32 a of the optical fiber 32) is 10 to 30 μm. The light from one pixel of the liquid crystal display panel 10 is
The light is guided by several light guide paths 31.

Since the light exit surface 30b of the light guide 30 is formed in a stepped shape, the light guided through each light guide path 31 is such that the light exit surface 30b of the light guide 30 is inclined with respect to the light guide direction. However, the light is efficiently emitted from the emission surface 30b. That is, the emission surface 3 of the light guide 30
If 0b is a steeply inclined surface with respect to the light guide direction, the light guided through each light guide path 31 is totally reflected by the emission surface 30b and is not emitted from the emission surface 30b. However, in the present embodiment, the light emitting surface 30b of the light guide 30 is formed in a stepped shape, and the light emitting surface of each light guide path 31 is a surface substantially perpendicular to the light guide direction. The incoming light is emitted from the exit surface 3
0b, the light exiting surface 3 is hardly reflected.
0b is emitted. In this case, if the exit surface 30b is a gentle slope with respect to the light guide direction, the light guided through each light guide path 31 will not be totally reflected by the exit surface 30b. The exit surface 30b of 30 may be an inclined surface instead of a stepped shape.

The light emitted from the light guide 30 is transmitted to the light guide 3 by the prism sheet 41 as the image forming means 40.
Since the light emitted from the prism sheet 41 is refracted in a direction substantially perpendicular to the light exit surface 30b, the light emitted from the prism sheet 41 is observed in the light exit direction, that is, a direction substantially perpendicular to the light exit surface of the prism sheet 41. Thus, an image formed by enlarging the image formed by the image light from the liquid crystal display panel 10 in one side direction (the direction of inclination of the step-like surface) can be seen.

FIG. 8 is a view showing an enlarged state of light emitted from the light guide 30. For example, light W having a width as shown in FIG. When the light enters the prism sheet 41, the light incident on each of the prism portions 42 is totally reflected by the prism portions 42, and is refracted as shown in the drawing, and exits from the prism sheet 41. As described above, the light W emitted from the light guide 30 is split into the same number as the number of the prism portions 42 formed on the prism sheet 41 and emitted from the prism sheet 41.

The prism section 42 of the prism sheet 41 is designed so that all the light emitted from the light guide 30 and incident on the prism section 42 is refracted toward the exit surface side of the prism sheet 41. Further, since the light emitted from the light guide 30 and traveling toward the prism portion 42 of the prism sheet 41 always enters one of the prism portions 42 in the incident area of the prism sheet 41 as shown in FIG. Most of the emitted light exits from the prism sheet 41 without loss.

Then, each divided light w which is divided into the same number as the number of the prism portions 42 and exits the prism sheet 41 is obtained.
1 ', w2', w3 ', and w4' are lights in which the widths of the lights w1, w2, w3, and w4 incident on the respective prism portions 42 are increased in the vertical direction in the drawing, and these divided lights w
The interval between 1 ', w2', w3 ', w4' is
The light W ′ emitted from the prism sheet 41 is divided into a plurality of lights W with respect to the light W emitted from the light guide 30 and the divided light w
This is an enlarged light in which the widths and intervals of 1 ', w2', w3 ', w4' are increased.

Therefore, the image light refracted by the prism sheet 41 and emitted is converted by the prism sheet 4.
When observed from a direction substantially perpendicular to 1, each pixel of the image formed by the image light from the liquid crystal display panel 10 is divided into a plurality of bright spots, and the interval between the bright spots is increased. An enlarged image with a high resolution is observed.
The angle of the prism portion 42 of the prism sheet 41 with respect to the light exit surface 30b of the light guide 30 may be set such that the light totally reflected by the prism portion 42 is substantially perpendicular to the light exit surface of the prism sheet 41. desirable.

FIG. 9 shows the outer shape of the image formed by the image light from the liquid crystal display panel 10 and the enlarged image emitted from the image forming means 40 comprising the prism sheet 41.
The enlarged image P ′ shown in FIG. 9B is an image P shown in FIG. 9A generated by image light from the liquid crystal display panel 10.
3 is an enlarged image obtained by stretching in the direction of one side (the direction of inclination of the step-like surface of the light guide 30).

That is, the enlarged image P 'is a screen-shaped pixel having the same horizontal width as the image P created by the image light from the liquid crystal display panel 10 and a vertical width larger than the vertical width of the image P. .

The enlarged image P 'is an image obtained by extending the image P formed by the image light from the liquid crystal display panel 10 in the vertical direction. The image P formed by the image light from the liquid crystal display panel 10 is Since the image is a horizontally long image compressed in the vertical direction of the screen, this enlarged image is observed as a normal image. This enlarged image P ′ is displayed on the liquid crystal display panel 10.
This is a high-definition image in which each pixel of the image P created by the image light from is divided into a plurality of bright spots and the number of dots is increased.

The magnification of the enlarged image P ′ (the magnification when the enlarged image is viewed from the direction perpendicular to the prism sheet 41) is determined by the vertical width of the incident surface 30 a of the light guide 30 and the light guide. 30 corresponds to the ratio to the vertical width of the prism sheet 41 disposed on the exit surface 30b side, and the ratio is the inclination angle of the prism sheet 41 with respect to the light guide direction of the light guide 30 (the stepped surface of the light guide 30). Θ).

For example, when the inclination angle θ of the prism sheet 41 is 11.5 °, the incident surface 30 of the light guide 30 is
The ratio of the vertical width of a to the vertical width of the prism sheet 41 is 1: 5.
Thus, an image obtained by magnifying the image generated by the image light from the liquid crystal display panel 10 five times vertically is displayed. Also,
When the inclination angle θ of the prism sheet 41 is 30 °, the ratio of the vertical width of the incident surface 30a of the light guide 30 to the vertical width of the prism sheet 41 is 1: 2, and the liquid crystal display panel 1
An image formed by enlarging the image created by the image light from 0 to 2 times vertically is displayed.

The inclination angle θ of the step-like surface of the light guide 30 is further enlarged by further reducing the inclination angle θ of the prism sheet 41 with respect to the light guide direction of the light guide 30. be able to.

In this embodiment, since the light is diffused and emitted by the light diffusing means 50 provided on the emission surface side of the image forming means 40 comprising the prism sheet 41, the enlarged image is excellent over a wide viewing angle. Observed in contrast.

As described above, the display device has the incident surface 30a for taking in the image light from the liquid crystal display panel 10, which is an image generator for emitting the image light, almost perpendicularly, and the emission surface 30b formed in an inclined shape. A light guide 30 having the light guide 30 and image forming means 40 for expanding image light emitted from the emission surface 30b of the light guide 30 along the inclined direction and emitting the image light. The image light from the liquid crystal display panel 10 is provided. In this display device, the image light from the liquid crystal display panel 10 is taken into the light guide 30 almost perpendicularly and emitted from the emission surface 30b. .

The light exit surface 30b of the light guide 30
Is a surface formed in an inclined shape (in this embodiment, stepwise), and the image light from the emission surface 30b is expanded by the image forming means 40 along the inclined direction and is emitted. When the emitted light is observed, an image obtained by enlarging an image formed by the image light from the liquid crystal display panel 10 in one side direction can be seen.

Therefore, according to this display device, a large-screen image can be obtained using the small-screen liquid crystal display panel 10 which can be obtained with good yield and at low cost. Moreover,
According to this display device, the emission surface 30b of the light guide 30
Is located in a region where the emission region (display region) of the liquid crystal display panel 10 is extended in a substantially vertical direction, and image light emitted from the emission surface 30b of the light guide 30 is emitted from the emission surface 30b.
The image forming means 40 is arranged along the plane and is enlarged and emitted along the inclination direction. Therefore, the depth dimension of the device viewed from the observation direction of the enlarged image is substantially equal to the width of the liquid crystal display panel 10. Therefore, it is possible to greatly reduce the thickness of the liquid crystal display panel as compared with a conventional projection type display device in which image light from a liquid crystal display panel is projected onto a screen placed at a position separated by a projection optical path length from a projection lens system.

Further, in this display device, the image light from the liquid crystal display panel 10 is taken into the light guide 30 almost vertically from the incident surface thereof, and is not diffused to the surroundings. Because the image reaches 30b, the enlarged image is a high-quality image without distortion.

Further, this display device has a liquid crystal display panel 1
The light guide 30 has a simple structure in which the light guide 30 is disposed on the emission side of the light guide 0, and the light guide 30 can be manufactured efficiently and at low cost as described above. Reference numeral 30 designates the incident surface 30a of the liquid crystal display panel
It can be manufactured at a very low cost as compared with a conventional projection type display device that requires an expensive projection lens system and requires accurate alignment thereof.

Further, in the above embodiment, the light guide 30
Is formed in a step shape, so that the light guide 3
Since the light guided to 0 is emitted from each of the steps formed in a step-like manner, that is, a plurality of surfaces substantially perpendicular to the light guide direction of the light guide 30, at high emission rates, the light guide 30 The guided image light can be efficiently emitted.

In the above embodiment, the image forming means 40
Since the prism sheet 41 that refracts and emits image light emitted from the emission surface 30b of the light guide 30 in a direction substantially orthogonal to the emission surface 30b is used,
The image light emitted from the zero emission surface 30b can be efficiently expanded and emitted along the inclined direction.

Further, in the display device, since the light diffusing means 50 is provided on the emission surface side of the image forming means 40, the viewing angle of the enlarged image can be widened. In addition, a light source unit 20 that supplies light to the liquid crystal display panel 10 includes:
Since the parallel light generating means 25 for converting the image light from the liquid crystal display panel 10 into parallel light and emitting the parallel light to the light guide is provided, most of the image light from the liquid crystal display panel 10 can be made to enter the light guide 30. As a result, the light efficiency can be improved.

When the light exit surface 30b of the light guide 30 is formed in a step shape as in the above embodiment, the light exit surface 30b
The light guide 30 may be formed by cutting out the light guide 30 in a stepped manner as shown in FIGS. 1 and 6B, but as shown in FIG. Is formed, and the back surface of the sheet member 36 whose surface is formed in a stepped shape is adhered to the inclined surface to form the stepped output surface 30b.
b can be easily formed.

The liquid crystal display panel 10 used in the display device of the above embodiment is of an active matrix type using a TFT 14 as an active element. This liquid crystal display panel 10 uses a non-linear resistance element such as a MIM as an active element. TN type or STN type simple matrix type liquid crystal display panel.

Further, the display device of the above embodiment uses the liquid crystal display panel 10 as an image generator. The image generator itself generates image light, for example, an electroluminescent display. Any of a panel, a plasma display, a cathode ray tube (CRT), and a laser display may be used.

In this case, when the parallel light generating means for converting the image light from the image generator into parallel light and outputting the parallel light to the light guide is provided, the parallel light generating means is provided between the image generator and the light guide. It may be provided.

FIG. 11 is a side view of a display device showing a second embodiment of the present invention. In this embodiment, a cathode ray tube (hereinafter referred to as CRT) is used as an image generator.
(A) shows a display device provided with parallel light generating means, and (b) shows a display device provided with no parallel light generating means.

The display device of this embodiment is a CRT 6
The light guide 30 is disposed on the emission side of the light guide 0, and the image forming unit 40 is provided in close proximity to the emission surface of the light guide 30;
The light diffusing means 50 is provided on the emission surface side of the image forming means 40. The light guide 30, the image forming means 40 and the light diffusing means 50 are the same as those used in the first embodiment. Since they are the same, the description is omitted.

The display device shown in FIG.
On the emission side of T60, parallel light generating means 61 for emitting image light from the CRT 60 into parallel light and emitting the parallel light to the light guide 30 is provided, and the light guide 30 is arranged on the emission side. The parallel light generating means 61 has one surface formed of CR
On the flat surface of the transparent support member 61a formed on a concave curved surface along the emission surface of T60 and the other surface formed on a flat surface,
A micro lens array 61b in which a large number of minute convex lenses are densely arranged is provided.

In the display device shown in FIG. 11B, the entrance surface 30 of the light guide 30 is directly connected to the exit surface of the CRT 60.
In this display device, the entrance surface 30a of the light guide 30 is formed as a concave curved surface along the exit surface of the CRT 60, and the entrance surface 30a is close to or in contact with the exit surface of the CRT 60. By making them face each other, most of the image light from the CRT 60 is made to enter the light guide 30 without loss.

FIG. 12 is a side view of a display device according to a third embodiment of the present invention. The display device of this embodiment includes an image generator (a liquid crystal display panel, an electroluminescence display) for emitting image light. Panel, plasma display, CR
T, laser display, etc.) Light guide 3 provided on the emission side of 70
0c, the inclined surface 30c formed by cutting the exit surface in a straight line.
Reflecting particles 37 for refracting light in various directions are dispersed on the emission surface 30c, and the emission surface 30c of the light guide 30 is dispersed.
And an image forming means for expanding the image light emitted from the camera along the inclined direction and emitting the same.

The light guide 30 in which the reflection particles 37 are dispersed on the exit surface 30c as described above is manufactured by mixing the reflection particles 37 in advance in the core of the optical fiber used for the light guide path. Can be.

According to the display device of this embodiment, the image light from the image generator 70 is taken into the light guide 30 almost perpendicularly from the incident surface 30a and is guided to the emission surface 30c of the light guide 30. Since the light is refracted from the reflective particles 37 in various directions and emitted, when the emitted light is observed from a direction substantially perpendicular to the emission surface 30c, the liquid crystal display panel 10
The image created by the image light from the
The image enlarged in the (b tilt direction) can be seen.

FIG. 13 is a perspective view of a display device showing a fourth embodiment of the present invention. The display device of this embodiment uses a liquid crystal display panel as an image generator that emits image light.

This display device comprises a liquid crystal display panel 10,
A light source unit 20 disposed behind the liquid crystal display panel 10
And a first liquid crystal display panel 10 disposed on an emission side of the liquid crystal display panel 10.
A light guide 30A, a first image forming means 40A arranged close to the light emitting surface of the first light guide 30A, and a light guide 30A arranged on the light emitting side of the first image forming means 40A. 2
The light guide 30B, the second image forming means 40B arranged in close proximity to the emission surface of the second light guide 30B, and the light guide 30B provided on the emission surface side of the second image formation means 40B And light diffusion means 50.

The liquid crystal display panel 10 and the light source unit 20
It has the same structure as that used in the first embodiment described above, but in this embodiment, the liquid crystal display panel 10
The light source unit 20 is designed to display an image with a normal aspect ratio, and the light source unit 20 is designed according to the size of the display area.

The first light guide 30A and the second light guide 3
In the same manner as the light guide 30 used in the first embodiment, each of the first light guides 0B has a structure in which a large number of linear light guides formed by the cores of the optical fibers are dense. Light body 30
In A, the shape of the cross section perpendicular to the light guide direction is substantially the same as the size of the optical image created by the liquid crystal display panel 10 (the area of the display area of the liquid crystal display panel 10),
The shape of the cross section of the second light guide 30B perpendicular to the light guide direction is such that the first light guide 30A is formed at a predetermined angle with respect to the light guide direction. The cross section obliquely cut at the same angle as the inclination angle of the light exit surface) has a substantially oblong shape.

The light guides (cores of optical fibers) of these light guides 30A and 30B have the same diameter, and the cross section of the second light guide 30B is smaller than the cross section of the first light guide 30A. Therefore, the number of light guide paths of the second light guide 30B is larger than the number of light guide paths of the first light guide 30A.

The first light guide 30A has an entrance surface for taking in the image light from the liquid crystal display panel 10 almost vertically, and an inclined exit surface.
The incident surface has a shape substantially the same as the size of an optical image formed by the liquid crystal display panel 10 and is cut substantially perpendicular to the light guide direction, and the exit surface is a light guide 30A.
Are cut out stepwise.

The second light guide 30B has an incident surface for taking in the image light emitted from the first light guide 30A almost vertically, and an emission surface formed in an inclined shape. ,
The incident surface is a horizontally long surface which is cut substantially perpendicular to the light guide direction and has substantially the same shape as the slope along the stepped emission surface of the first light guide 30A. Light body 3
OB is cut out in a stepwise shape that is inclined along the width direction of the horizontally long entrance surface.

Further, the first image forming means 40A and the second image forming means 40B are composed of, for example, a prism sheet similar to the prism sheet 41 used in the first embodiment. The means 50 is, for example, a light diffusion sheet similar to that used in the first embodiment.

Then, the first light guide 30A has its entrance surface parallel and close to the exit surface of the liquid crystal display panel 10, or has its entrance surface in contact with the exit surface of the liquid crystal display panel 10. The first image forming means 40A is arranged along the light emitting surface of the first light guide 30A.

Further, the second light guide 30B has its incident surface facing the output surface of the first image forming means 40A in parallel or close thereto, or the incident surface of the second image forming means 40A. The second image forming means is arranged so as to be in contact with the light exit surface, with the direction of inclination of the light exit surface oriented substantially perpendicular to the direction of inclination of the light exit surface of the first light guide 30A. 40B is disposed along the emission surface of the second light guide 30B, and the light diffusing means 50
Is provided.

In the display device of this embodiment, the image light from the liquid crystal display panel 10 is guided by the first light guide 30A, and the light emitted from the emission surface is directed by the first image forming means 40A in the tilt direction. The image light from the liquid crystal display panel 10 is enlarged in one side direction, and the image light is guided by the second light guide 30 </ b> B, and the light emitted from the emission surface is changed to the second direction. The image light is further expanded in the direction of another side by expanding the light along the inclined direction and emitting the light by the second image forming means 40B.

According to this display device, the liquid crystal display panel 1
The image light from 0 is emitted to the first image forming unit 40A via the first light guide 30A to become image light enlarged in one side direction, and the image light is converted to the second light guide 30A.
Since the image light is emitted from the second image forming unit 40B via B, the image light is enlarged in the other side direction, and thus the image formed by the image light from the liquid crystal display panel 10 is displayed in one side direction and the other side direction. An enlarged image can be obtained.

FIG. 14 shows an enlarged state of an image in this display device. An image P0 formed by image light from the liquid crystal display panel 10 is first guided through the first light guide 30A to the first light guide 30A. Out of the image forming means 40A becomes a first enlarged image P1 enlarged in one side direction, and the image P1 is guided through the second light guide 30B and emitted from the second image forming means 40B. Is enlarged in the other side direction to form a second enlarged image P3 similar to the image P0 formed by the image light from the liquid crystal display panel 10.

Here, the first enlarged image P1 is the first enlarged image P1.
As described in the embodiment, each pixel of the image P0 formed by the image light from the liquid crystal display panel 10 is divided into a plurality of bright points, and the interval between the bright points is increased. , The second enlarged image P3 is the first enlarged image P3.
Is an image in which each bright spot of the enlarged image P1 is further divided into a plurality of bright spots and the interval between the bright spots is increased.

Although the display device of this embodiment uses two light guides 30A and 30B, the emission surface of the first light guide 30A is formed in the emission area of the liquid crystal display panel 10 (display area). Area) extending in the substantially vertical direction, and the emission surface of the second light guide 30B extends the emission area of the liquid crystal display panel 10 in the substantially vertical direction to the first light guide. The second image forming apparatus is located in a region extending in a direction substantially perpendicular to the light exit surface of the light body 30A, and the image light emitted from the second light guide 30B is arranged along the light exit surface. Since the device 40B enlarges and emits the light along the direction of its inclination, the depth dimension of the device viewed from the observation direction of the enlarged image is substantially equal to the width of the liquid crystal display panel 10, and therefore, the image light of the liquid crystal display panel Is the projection optical path length from the projection lens system Compared to the display device of the conventional projection type for projecting on a screen placed at separate positions, it is possible to achieve a substantial reduction in thickness.

FIG. 15 is a perspective view of a display device showing a fifth embodiment of the present invention. This display device uses the liquid crystal display panel 10 as an image generator that emits image light.

This display device is similar to the liquid crystal display panel 10 described above.
And a light guide 30 having an incident surface 30a for taking in the image light from the liquid crystal display panel 10 substantially vertically and an emission surface 30b formed in an inclined shape. The image generating means 100 is configured such that the side edges of the emission surfaces 30b of the respective light guides 30 are arranged close to each other to constitute a composite image generating means. Image forming means 40 is provided which refracts the composite image light emitted from the image generating means in a direction substantially perpendicular to the light emitting surface 30b of the light guide 30 and expands and emits it along an inclined direction. Is provided with a light diffusing means 50.

The liquid crystal display panel 10 constituting the image generating means 100 and the light source section 20 disposed behind the liquid crystal display panel 10
Since the light guide 30 has the same configuration as that used in the first embodiment, the description thereof will be omitted by attaching the same reference numerals to the drawings. The image forming unit 40 provided on the emission side of the composite image generating unit is, for example, a prism sheet,
The light diffusion means 50 is, for example, a light diffusion sheet.

In this embodiment, two sets of image generating means 100 are arranged one above the other to form a composite image generating means. The entire image generating means is arranged obliquely so that the surface along the outgoing surface (stepped surface) 30b is aligned on one vertical plane.

The upper image generating means 10 in FIG.
0, the length of the light guide 30 is made longer than that of the light guide 30 of the lower image generating means 100 in consideration of the arrangement space of the liquid crystal display panel 10 and the light source unit 20, and the lower image is formed. It is provided with a tilt angle that is somewhat smaller than the tilt angle of the generating means 100, that is, in a tilted state that is separated from the lower image generating means 100 toward the arrangement side of the liquid crystal display panel 10.

That is, the display device of this embodiment is basically a display device of the above-described first embodiment which is vertically overlapped. According to this display device, a plurality of liquid crystal display panels 10 are provided. Can be displayed as one enlarged image connected to each other at the side edges thereof.

Further, according to this display device, since the image light emitted from the emission surface 30b of the light guide 30 of each image generating means 100 is expanded by the image forming means 40 along the inclination direction and emitted, Compared with a conventional projection display device that projects image light from an image generator onto a screen placed at a position separated by a projection optical path length from a projection lens system, the thickness can be significantly reduced.

As in this embodiment, the inclination angle of the upper image generation means 100 is made smaller than the inclination angle of the lower image generation means 100, and the light guide 30 of both image generation means 100 In order for the surface along the emission surface 30b to be aligned on one vertical surface, the inclination angle of the stair-like surface, which is the emission surface 30b of the light guide 30 of the upper image generating means 100, with respect to the light guide direction, Light guide 30 of lower image generating means 100
Need to be larger (loose) than that of

For this reason, in this display device, an image enlargement system composed of the upper image generating means 100 and the image forming means 40, and a lower image generating means 100 and the image forming means 40 are constituted. Although the enlargement ratio differs from that of the image enlargement system, the liquid crystal display panel 10
Is to display an image having a compression rate smaller than the compression rate (compression rate in the vertical direction) of the display image of the liquid crystal display panel 10 of the lower image generation means 100. The liquid crystal display panel 1
If a cross-sectional area that matches the width of the display area of 0 is used,
The size of the dots of the enlarged images displayed by the upper and lower image enlargement systems can be made the same.

FIG. 16 is a perspective view of a display device showing a sixth embodiment of the present invention. The display device includes an image generator (a liquid crystal display panel, an electroluminescence display panel, a plasma display device, a CRT, a laser display device, or the like) 70 that emits image light, and an image light from the image generator 70 that is substantially vertical. And a light guide 30 having a light emitting surface 30a and a light emitting surface 30b formed in an inclined shape. The composite image generating means is constituted by arranging the side edges of the image generating means 30b closely to each other. In this embodiment, two sets of image generating means 10 are provided.
0 are arranged side by side.

The two sets of image generating means 100 are tilted so as to be separated from each other to the left and right toward the arrangement side of the liquid crystal display panel 10 in consideration of the arrangement space of the image generator 70. The two image generating means 100 are provided so that the surfaces of the light guides 30 along the emission surface 30b are aligned on one vertical surface.

Although not shown in FIG. 16, the composite image light emitted from the composite image generating means is provided on the emission side of the composite image generating means with the light exit surface 30b of the light guide 30.
Image forming means for refracting the light in a direction substantially perpendicular to the direction and expanding and emitting the light along the inclined direction, and a light diffusing means on the light exit side.

That is, the display device of this embodiment is basically a display device similar to that of the first embodiment described above, which is arranged on the left and right. A plurality of images obtained by enlarging images formed by image light from the body 70 in one side direction can be displayed as one enlarged image connected to each other at the side edges.

Further, according to this display device, the image light emitted from the emission surface 30b of the light guide 30 of each image generating means 100 is expanded by the image forming means 40 along the inclined direction and emitted. Compared with a conventional projection display device that projects image light from an image generator onto a screen placed at a position separated by a projection optical path length from a projection lens system, the thickness can be significantly reduced.

The display device according to the fourth embodiment has a plurality of image generating means 100 stacked vertically, and the display device according to the fifth embodiment has a plurality of image generating means 1.
00 are arranged side by side on the left and right, but a configuration combining these embodiments, that is, four or more sets of image generating means 100
Are arranged vertically and horizontally to form a composite image generating means, so that an even larger screen image can be displayed.

[0127]

According to the display device of the present invention, the image light from the image generator is taken almost perpendicularly to the light guide and emitted from the inclined exit surface, and the image light is formed into the image. When the emitted light is observed by observing the emitted light, an image obtained by enlarging the image formed by the image light from the image generator in one side direction can be seen. Therefore, according to this display device, a large-screen image can be obtained using a small-screen image generator that can be obtained with good yield and at low cost.

In addition, according to this display device, the image light emitted from the emission surface of the light guide is enlarged and emitted along the inclined direction by the image forming means, so that the image light of the image generator is projected onto the projection lens. Compared to a conventional projection display device that projects onto a screen placed at a position separated by a projection optical path length from the system, the thickness can be significantly reduced.

Further, in this display device, the image light from the image generator is taken into the light guide substantially perpendicularly from the incident surface thereof, and reaches the emission surface of the light guide without diffusing to the surroundings. The enlarged image is a high-quality image without distortion.

Further, this display device has a simple structure in which the light guide is arranged on the emission side of the image generator, and the light guide is provided only with its incident surface facing the image generator. For this reason, it can be manufactured at extremely low cost as compared with a conventional projection type display device which requires an expensive projection lens system and requires accurate alignment thereof.

[0131] In the display device of the present invention, it is desirable that the light emitting surface of the light guide is formed in a step-like manner. In this case, the light guided through the light guide is formed in each step-like shape. Since the light is emitted at high emission rates from the surfaces, that is, the plurality of surfaces substantially perpendicular to the light guide direction of the light guide, the image light guided by the light guide can be efficiently emitted.

It is preferable that the image forming means is configured to refract image light emitted from the light emitting surface of the light guide in a direction substantially perpendicular to the light emitting surface and emit the light. If the means is adopted, the image light emitted from the emission surface of the light guide can be efficiently expanded and emitted along the inclined direction.

Further, in this display device, light diffusion means is provided on the emission surface side of the image forming means .
I, it is possible to widen the viewing angle, also by providing the parallel beam generating means for emitting a light guide in the parallel light image light from the image generator, most of the image light from the image generator To the light guide to improve the light efficiency.

Further, in the display device according to the present invention, it is preferable that the image forming means refracts the image light emitted from the emission surface of the light guide in a direction substantially perpendicular to the emission surface and emits the image light. Desirably, if such an image forming means is employed, the image light emitted from the emission surface of the light guide can be efficiently expanded and emitted along the inclined direction.

When the light emitting surface of the light guide is formed in a step shape, the light emitting surface may be formed by cutting the light guide in a step shape or by cutting the light guide in a straight line. The inclined surface may be formed, and the back surface of a member having the surface formed in a stepped shape may be adhered to the inclined surface, but according to the latter,
A stepped emission surface can be easily formed.

Further, another display device of the present invention comprises an image generator that emits image light, an incident surface that captures the image light from the image generator almost vertically, and an emission surface that is formed in an inclined shape. A first light guide having: a first image forming means for enlarging image light emitted from an emission surface of the first light guide along an inclined direction and emitting the image light; A second light guide having an incident surface that comes into contact with the forming means and captures the image light emitted from the emission surface, a second light guide having an inclined emission surface, and an emission surface of the second light guide. A second image forming means for expanding the emitted image light along the tilt direction and emitting the image light, and displaying an image formed by the image light from the image generator in an enlarged manner. According to the display device, the image light from the image generator is transmitted through the first light guide to the first image. The image light is expanded in one side direction by emitting the image forming means, and the image light is expanded in the other side direction by emitting the second image forming means through the second light guide. Since the light becomes light, it is possible to obtain an enlarged image obtained by enlarging the image formed by the image light from the image generator in one side direction and the other side direction.

Further, another display device of the present invention has an image generator for emitting image light, an incident surface for taking image light from the image generator almost vertically, and an inclined output surface. A plurality of image generating means comprising a light guide, a composite image generating means in which the plurality of image generating means are arranged such that the side edges of the light emitting surfaces of the respective light guides are in close contact with each other, and Image forming means for refracting the emitted composite image light in a direction substantially perpendicular to the emission surface and expanding the emitted light along an inclined direction, and displaying a plurality of images integrally. According to the display device, it is possible to display a plurality of images obtained by enlarging the images formed by the image light from the plurality of image generators in one side direction as an integrated enlarged image connected to each other at the side edges.

[Brief description of the drawings]

FIG. 1 is a side view of a display device showing a first embodiment of the present invention.

FIG. 2 is a perspective view of an optical fiber constituting a light guide and a perspective view of an assembly rod thereof.

FIG. 3 is a diagram showing a method of manufacturing an optical fiber assembly which is a material of a light guide.

FIG. 4 is a perspective view of an optical fiber assembly.

FIG. 5 is an enlarged sectional view of one optical fiber collecting rod portion of the optical fiber assembly.

FIG. 6 is a diagram showing a method of manufacturing a light guide from an optical fiber assembly.

FIG. 7 is a diagram showing another configuration of the light guide.

FIG. 8 is a diagram showing an enlarged state of light emitted from the light guide.

FIG. 9 is a diagram illustrating an image formed by image light from a liquid crystal display panel as an image generator and an outer shape of an enlarged image emitted from an image forming unit.

FIG. 10 is an equivalent circuit diagram illustrating a pixel electrode, a TFT, and the like provided on one substrate of a liquid crystal cell of a liquid crystal display panel.

FIG. 11 is a side view of a display device showing a second embodiment of the present invention.

FIG. 12 is a side view of a display device showing a third embodiment of the present invention.

FIG. 13 is a perspective view of a display device showing a fourth embodiment of the present invention.

FIG. 14 is a diagram illustrating an enlarged state of an image on the display device according to the fourth embodiment.

FIG. 15 is a perspective view of a display device showing a fifth embodiment of the present invention.

FIG. 16 is a perspective view of a display device showing a sixth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display panel 20 ... Light source part 30 ... Light guide 30a ... Incident surface 30b, 30c ... Outgoing surface 31 ... Light guide path 40 ... Image forming means 50 ... Light diffusing means 70 ... Image generator

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-194429 (JP, A) JP-A-63-95419 (JP, A) JP-A-60-241025 (JP, A) JP-A 49-194 99499 (JP, A) JP-A-4-42191 (JP, A) JP-A-52-93351 (JP, A) JP-A-5-5873 (JP, A) JP-A-2-19002 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) G09F 9/00, 9/30

Claims (10)

(57) [Claims] 1. An image generator that emits image light, an incident surface that captures image light from the image generator almost perpendicularly, and a plurality of surfaces that are substantially perpendicular to the light guide direction and have a plurality of steps.
A light guide having an emission surface formed obliquely with respect to the light guide direction, and image light emitted from the emission surface of the light guide is incident,
A prism portion that refracts in a direction substantially perpendicular to the light exit surface of the light guide, and expands and emits light along an inclined direction of the light exit surface.
An image forming unit having a forming surface ; and a light diffusing unit that receives image light emitted from the image forming unit, diffuses the image light, and emits the image light. A display device, wherein an image to be created is enlarged and displayed in one side direction. 2. A parallel light generating means for converting image light from an image generator into parallel light and outputting the parallel light to a light guide,
The display device according to claim 1 , wherein light efficiency is improved. Wherein the image generator is adapted to emit by changing the light from the light source into image light, the collimated light generating means according to claim 2, characterized in that provided on the light source unit Display device. 4. The image generator itself generates image light, and the parallel light generating means is provided between the image generator and the light guide. 2
The display device according to claim 1. 5. The display device according to claim 1 , wherein the light guide is formed of a light guide path made of resin. 6. The display device according to claim 1, wherein the image generator is any one of a liquid crystal display panel, an electroluminescent display panel, a plasma display device, a cathode ray tube, and a laser display device. 7. A staircase having a plurality of image generators for emitting image light, an incident surface for capturing image light from the image generator substantially vertically, and a plurality of surfaces substantially perpendicular to the light guide direction.
A light guide having an emission surface formed by cutting out in an inclined manner with respect to the light guide direction, and image light emitted from the emission surface of the light guide being incident thereon,
An image forming means having a prism portion forming surface which refracts in a direction substantially perpendicular to the light emitting surface of the light guide and expands and emits along the inclination direction of the light emitting surface; Light diffusing means to which the image light is incident and which diffuses and emits the image light, wherein an image formed by the image light from the image generator is enlarged and displayed in one side direction. Display device. 8. An image generator that emits image light, an incident surface that captures image light from the image generator almost perpendicularly, and is formed by cutting linearly inclining with respect to the light guide direction. Inclined surface, surface almost perpendicular to light guide direction
Are formed in a step shape having a plurality of
A light guide formed so as to be inclined with respect to the light guide direction to form an emission surface by bringing a back surface of the member formed into an inclined shape into close contact with the inclined surface, and emitted from an emission surface of the light guide. Image light is incident,
An image forming means having a prism portion forming surface which refracts in a direction substantially perpendicular to the light emitting surface of the light guide and expands and emits along the inclination direction of the light emitting surface; Light diffusing means to which the image light is incident and which diffuses and emits the image light, wherein an image formed by the image light from the image generator is enlarged and displayed in one side direction. Display device. 9. A staircase having a plurality of image generators for emitting image light, an incident surface for capturing image light from the image generator substantially perpendicularly, and a surface substantially perpendicular to the light guide direction. A first light guide that is formed and has an emission surface formed to be inclined with respect to the light guide direction; and a prism portion formation surface on which a plurality of prism portions are formed. The image light emitted from the emission surface of the first light guide is incident on the light guide, and the incident image light is refracted in a direction substantially orthogonal to the emission surface of the first light guide, and The first that expands and emits along the surface inclination direction
And a plurality of surfaces substantially perpendicular to the light-guiding direction and having a plurality of surfaces that are in contact with the first image forming unit and capture the image light emitted from the emission surface. A second light guide having an emission surface formed to be inclined with respect to the light guide direction, and a prism portion formation surface on which a plurality of prism portions are formed. The image light emitted from the exit surface of the second light guide is incident, and the incident image light is refracted in a direction substantially orthogonal to the exit surface of the second light guide, and The second light that expands and emits along the inclination direction of
An image formed by the image light from the image generator, comprising: an image forming unit; and an image diffusion unit that receives the image light emitted from the image forming unit, diffuses the image light, and emits the image light. A display device characterized by displaying an enlarged image. A plurality of image generators for emitting 10. The image light, said an incident surface to capture substantially vertically the image light from the image generator, includes a plurality of substantially a plane perpendicular light guiding direction A plurality of light guides formed in a step-like manner and having an emission surface formed to be inclined with respect to the light guide direction; and a plurality of image generation means. A composite image generating means in which the side edges of the light emitting surfaces of the light guides are arranged close to each other, and the inclination directions of the light emitting surfaces of the light guides are aligned, and a prism portion forming surface on which a plurality of prism portions are formed. The prism portion forming surface refracts the composite image light emitted from the composite image generating means in a direction substantially orthogonal to the emission surface of each of the light guides, and a plurality of light beams correspond to the plurality of prism portions. Divided, along the direction of inclination of the exit surface of each light guide Image forming means for enlarging and emitting, and light diffusing means for receiving image light emitted from the image forming means, diffusing and emitting the image light, and integrally displaying a plurality of images. A display device characterized by the above-mentioned.