KR20040056526A - A display system using a waveguide screen - Google Patents

Abstract

PURPOSE: A display using a light guide screen is provided to effectively reduce the thickness of a projection display system having a large screen. CONSTITUTION: A display system includes a light source(31), an optical lighting system(33), a display device(32), light guide connectors(34), and light guide screens(35). The optical lighting system irradiates lights generated from the light source. The display device is electrically operated in response to an input video signal to control the intensity of the irradiated lights to display the image corresponding to the video signal. The light guide connectors are as many as the number of pixels of the display device and transmits the intensity of radiation of the image to the light guide screen. The light guide screens are as many as the number of the pixels of the display device and the number of light guides of the light guide connectors and displays the image on a large screen.

Description

Display device using an optical waveguide screen {A display system using a waveguide screen}

Recently, a flat panel display that has a small thickness and a large screen at the same time has been attracting attention by replacing a conventional CRT having a limited screen size and a large system size. Such large-screen flat panel displays include liquid crystal displays (LCDs), plasma displays (PDPs), projection systems, and the like. In addition, consumer demand for a wall-mounted display device that can hang on a wall with a small space while displaying a large screen is increasing.

In general, a liquid crystal projection apparatus transmits light from a light source to a liquid crystal panel and forms an image of the liquid crystal panel on a screen using a projection optical system to view an image formed on the screen. When the projection TV device is configured by directly projecting the image of the liquid crystal panel onto the rear screen, the projection distance must be secured between the screen and the projection optical system, so that a large amount of space is required behind the screen, and the size of the projection TV device becomes very large. have.

The configuration of a general liquid crystal projection apparatus has a structure as shown in FIG. Light emitted from the light source 11 is irradiated to the liquid crystal panel 12. The light incident on the liquid crystal panel 12 displays an image by the image signal of the liquid crystal panel 12 and forms an image on the rear screen 15 by the projection optical system 13 to view an image.

The image projected by the projection optical system 13 is reflected by the mirror 14, the path of light is bent and proceeds toward the rear screen 15 to form an image on the rear screen 15.

If you use the mirror to project light directly from the back of the rear screen without breaking the path of the light, it becomes the same as the dotted line of Fig. 1 and the system becomes very thick, so you can fold the path of light using the mirror to The same thickness can be reduced to reduce the overall system thickness.

However, in the projection system of the prior art, when the tilt angle of the mirror is increased to reduce the thickness of the system, the projection optical system is configured by folding the light propagation path so that the projection optical system portion is located in front of the system as shown in FIG. The rear projection system is not configured. Therefore, in the related art, the projection angle of the projection optical system and the placement angle of the mirror are limited, so that the thickness of the system can be reduced (solid line) rather than the thickness (dashed line) of the system that does not use the mirror.

Also, as shown in (b) of FIG. 2, when the mirror angle is increased and the projection optical system portion is arranged at an angle, the optical system can be arranged inside the system unlike in FIG. 2 (a), so that the system thickness when using the mirror (solid line) Although it can be greatly reduced than the system thickness (dotted line) when it is not used, the distance from the projection optical system to the rear screen varies for each position, and the magnification varies for each image forming position on the rear screen. As a result, a distorted image is formed, and since the projection direction is upward of the screen, brightness is changed according to the height of the screen.

As described above, the projection TV apparatus of the prior art has to adjust the optical path so that the image is projected on the rear screen without distortion, and thus the projection angle and arrangement of the projection optical system and the placement angle of the mirror are limited. It is difficult to reduce, and the overall system is large, thick, and has a problem of taking up a lot of space, so it is difficult to implement a thin display such as a wall-mounted display that has recently been in high demand.

The present invention is to solve the above problems to effectively reduce the system thickness of the large-screen projection display device to configure a large-screen display device.

Accordingly, the present invention intends to configure a projection apparatus for providing an image that is thin and does not cause distortion or brightness difference of an image.

1 is a block diagram of a conventional projection TV

2 is a problem when implementing a conventional thin display

3 is a block diagram of a display device of the present invention;

4 is a configuration diagram of an optical waveguide of the present invention

5 is a configuration and arrangement of the optical waveguide connecting portion of the present invention

Figure 6 is a cross-sectional structure of the optical waveguide screen of the present invention

Figure 7 is a cross-sectional structure of the optical waveguide connecting portion of the present invention

11, 21, 31: light source 12, 22, 32: LCD panel 13, 23, 33: projection optical system

14,24: mirror 15,25,35: rear screen 34: optical waveguide connection

35 optical waveguide screen 41 core 42 cladding

51: pixel 52: optical waveguide 61: optical waveguide incidence length

62: optical waveguide exit portion length 63: optical waveguide tilt angle

71: display element pixel 72: optical waveguide connection part incident part

73: optical waveguide connector 74: optical waveguide connector

75: optical waveguide screen incidence

The configuration of the present invention for achieving the above object is as follows. An illumination optical system for collecting and illuminating a light source and the light of the light source, a display device for displaying an image by adjusting an amount of light to be irradiated, and an optical waveguide connection unit for transmitting an amount of light of a corresponding image of the display device corresponding to each pixel of the display device It consists of an optical waveguide screen that displays the amount of light in a large screen.

The display element is electrically driven according to an input image signal to adjust an amount of light to display an image of the corresponding image signal, and the optical waveguide connecting portion is a combination of optical waveguides, which is configured as the number of pixels of the display device and displayed on the pixel. The amount of light in the image is transmitted to the screen as an optical waveguide. In addition, the optical waveguide screen is a combination of optical waveguides and is configured to match the number of pixels of the display device and the number of optical waveguides of the optical waveguide connection portion, and the screen is formed so as to correspond to the pixels of the display element on the front of the projection display device while traveling the light toward the observer. An image is displayed on the screen.

By the above configuration, the optical system and the reflection mirror required in the conventional projection display apparatus are removed, thereby effectively reducing the thickness of the system and configuring a thin, large display device.

The following is a description of a detailed embodiment using the drawings.

3 is a block diagram showing a configuration of the present invention.

The light source 31 and the illumination optical system 32 for collecting and illuminating the light of the light source, the display element 33 for displaying an image by adjusting the light quantity of the irradiated light, and the light amount of the corresponding image of the display element corresponding to each pixel of the display element. It consists of an optical waveguide connecting portion 34 for transmitting the optical waveguide screen 35 for displaying the light amount of the image on a large screen.

The display device having the above configuration has the following operation principle. First, the light emitted from the light source 31 is irradiated to the display element 33 by the illumination optical system 32. The light source 31 may be a high pressure mercury lamp, a metal halide lamp, or a white LED lamp generally used in a projection display device.

The display element 33 is driven by an electrical signal according to the input image signal to adjust the amount of light irradiated to the display element for each pixel to display an image of the corresponding image signal.

As the display device, a transmissive LCD for adjusting the amount of light transmitted or a reflective LCD for adjusting the amount of reflected light or a digital micromirror display (DMD) may be used.

Light adjusted by the display element is incident on the optical waveguide connector 34.

As a result, the thickness of the entire system can be drastically reduced like a solid line.

4 is a configuration of an optical waveguide used in the present invention. The optical waveguide connection portion 34 is composed of a core 41 at the center and a cladding 42 surrounding the core. The refractive index n1 of the core of the optical waveguide is larger than the refractive index n2 of the cladding so that the incident light does not escape to the outside due to the total reflection phenomenon. The optical waveguide may be used as the optical waveguide. The optical waveguide of the optical waveguide connecting portion 34 is matched with the number of pixels of the entire image of the display element so that each corresponding pixel corresponds to each optical waveguide.

For example, in the case of an image having a resolution XGA (1024 X 768), 786,432 optical waveguides are configured to correspond to each pixel.

5 is a configuration and arrangement of an optical waveguide connection unit according to an embodiment of the present invention. As shown in the figure, an optical waveguide 52 is connected to correspond to each pixel 51 of the display element to transmit light. Light of each pixel having the optical waveguide connector 34 is incident on the optical waveguide screen 35 with corresponding image information. The incident portion of the optical waveguide screen 35 is connected to the optical waveguide connecting portion 34 to correspond to each pixel of the display element. The exit portion of the optical waveguide screen 35 forms an image plane in the screen position of the entire system and displays an image by implementing an arrangement of pixels on the screen in proportion to the size of the entire screen.

For example, if the screen size is a 50-inch HD image (1280 X 720) with an aspect ratio of 16: 9, the size of one optical waveguide constituting the optical waveguide screen 35 on the screen is about 0.86 mm X 0.86 mm. do. That is, the size of the optical waveguide constituting the optical waveguide screen can be set according to the size of the screen constituting the screen of the system.

6 shows the relationship between the pixel size of the optical waveguide screen and the overall thickness of the optical waveguide screen as the cross-sectional structure of the optical waveguide screen in the configuration of the present invention. It is connected to the optical waveguide connecting portion 34 from the bottom and changes the optical path to the right to form a screen surface.

In one optical waveguide, the length 61 of the optical waveguide incidence portion is continuously arranged to represent the thickness of the display system. On the other hand, the length 62 of the exit portion of the optical waveguide is the size corresponding to one pixel on the entire screen. The length 62 of the optical waveguide exit portion is arranged in the vertical direction to achieve the vertical resolution of the screen according to the number thereof, and is arranged in the horizontal direction to form the horizontal resolution of the screen according to the number thereof.

The length 61 of the incidence portion of the optical waveguide can be made small so that the thickness of the entire system can be reduced. By adjusting the inclination angle 63 of the optical waveguide, a desired pixel size can be obtained at the output portion of the optical waveguide.

As a result, the size of the large screen can be realized while making the system thinner. In order to more efficiently transmit light when connecting the optical waveguide connector 34 and the incident part of the optical waveguide screen 35, the shape of the optical waveguide connector 34 may be set.

Since the optical waveguide connector 34 connects the display element 33 and the optical waveguide screen 35, the incidence portion of the optical waveguide connector is configured to be small to match the pixel size of the display element, and the exit portion of the optical waveguide connector is a pixel of the optical waveguide screen. It can be largely configured to fit the size. That is, when the incidence portion of the optical waveguide connection portion is narrow and the outflow portion is widened, light can be efficiently transmitted.

Figure 7 shows a cross-sectional structure of the optical waveguide connecting portion of the present invention described above.

In order to implement a color image on the screen, each pixel of the display device must produce a color image. Alternatively, color pixels may be realized when each pixel of the display device sequentially displays R, G, and B images at high speed.

By such a method, the optical system, the reflection mirror, and the like are removed from the conventional large-screen projection display device, thereby effectively reducing the overall thickness of the system, thereby making it possible to construct a thin large-screen display system.

The following effects can be expected in the thin display apparatus which employ | adopted the structure of this invention.

First, by removing the optical system and the reflection mirror of the projection display device, it is possible to effectively reduce the thickness of the entire system to realize a thin large screen device.

In addition, it is possible to implement an efficient and bright image by transferring the light amount of the image represented by the display element to the screen without loss.

Claims (5)

The light source 31 and the illumination optical system 32 for collecting and illuminating the light of the light source, the display element 33 for displaying an image by adjusting the light quantity of the irradiated light, and the light amount of the corresponding image of the display element corresponding to each pixel of the display element. Display device using an optical waveguide screen consisting of an optical waveguide connecting portion 34 for transmitting the optical waveguide screen 35 and a light waveguide screen 35 for displaying the light quantity of the image on a large screen The display apparatus using an optical waveguide screen according to claim 1, wherein the optical waveguide connecting portion corresponds the corresponding pixel to each optical waveguide by matching the optical waveguide with the number of pixels of the entire image of the display element 33. The display apparatus using the optical waveguide screen of claim 1, wherein an incident portion of the optical waveguide screen 35 is connected to the optical waveguide connecting portion 34 to correspond to each pixel of the display device. The light emitting part of the optical waveguide screen 35 forms a plane at the front screen position of the entire system and displays an image by implementing an arrangement of pixels on the screen in proportion to the size of the entire screen. Display device using waveguide screen The display apparatus using the optical waveguide screen, characterized in that the optical waveguide connecting portion is an optical fiber.