JPS63114489A - Projection type display device - Google Patents

Abstract

PURPOSE:To improve a contrast ratio and a color reproductivity by reversing the input sequence of a color light reflected on a dichroic mirror for synthesizing the respective color lights and a video signal to the source line of an active matrix liquid crystal light value used for transmitted color light. CONSTITUTION:A substrate 2 on which a polysilicon thin film transistor and an opposite substrate having a shading layer are assembled on a liquid crystal cell through a spacer and a gap agent to seal a liquid crystal. When a source driving IC5 gang bonded to a flexible substrate 4 is connected to a liquid crystal panel through a soldering, the liquid crystal light valve for green and the liquid crystal valve for red, blue are vertically opposed. Then, a gate driving IC6 gang bonded to the flexible substrate 4 is mounted in the liquid crystal panel and finally connected to a frame form rigid substrate 1. Thereby, since the respective incident lights can be made incident, the deterioration in the contrast ratio can be prevented, the display characteristic of the respective panels is equal and the color reproductivity is improved.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a projection display device.

[Conventional technology]

Conventional projection display devices using multiple liquid crystal light valves separate collimated light from a light source into red (R), green (G), and blue (B) components through a dichroic mirror, and produce each color of light. A liquid crystal light valve is used to perform optical switching for each component, and the R2O and B color components are combined again via a dichroic mirror, and a projection image is formed by a projection optical system.The above-mentioned color lights are reflected by the dichroic mirror that combines them. The liquid crystal light valve used for colored light is arranged so that the colored light enters from the side of the substrate that has the switching element, and the liquid crystal light valve used for transmitted colored light is arranged so that the colored light enters from the opposite substrate to reverse the image. I was preventing it.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional technology, since the light blocking layer of the switching element is on the opposite substrate side, in the liquid crystal light valve used for reflected colored light, the light directly enters the switching element and cannot be held sufficiently by the pixel electrode. However, there are problems in that the contrast ratio decreases and the image flickers.

The present invention solves these problems, and its purpose is to provide a bright image with a high contrast ratio without flickering.

[Means for solving problems]

Using a dichroic mirror, the light from the light source is divided into red, green,
In a projection type display device that separates blue light into each color light, switches the color light through three active matrix liquid crystal light valves, combines it again with a dichroic mirror, and forms a projected image with a projection optical system. A liquid crystal light used for colored light that is guided to a projection optical system by reflection in a dichroic mirror that synthesizes colored light.

It is characterized in that the input direction of the video signal of the pulp is different from the input direction of the video signal of the liquid crystal light valve used for color light guided to the projection optical system by transmission.

[Example 1] This example will be described below based on the drawings. Figure 1 (α
) is a plan view of the G liquid crystal light valve, and Fig. 1 Cb)
1 is a plan view of an R and B liquid crystal light valve. TIFT with polysilicon thin film transistor (T?T) formed
A liquid crystal cell was assembled using a substrate 2 and a counter substrate 3 having a light shielding layer via a spacer and a gap agent, and liquid crystal was sealed to obtain a liquid crystal panel.

Next, when connecting the source driving device C5 to the flexible substrate 4 by gang-bonding to the liquid crystal panel with solder, the G liquid crystal light valve and the R and B liquid crystal light valves should be upside down. Next, the gate drive member C6 is bonded to the substrate 4 by 7 lexicon and mounted on the liquid crystal panel, and finally connected to the frame-shaped rigid substrate 1.

A projection type display device was manufactured using the three liquid crystal light screens for R, G, and B described above. The optical system configuration diagram is shown in FIG. 2. Incident light from a halogen lamp 1 equipped with an elliptical spherical mirror is focused by a lens 2, and incident on a dichroic mirror 3 where it is separated into R, G, and B components. The separated components are made to enter the liquid crystal light valve 40 for R, G, and B from the opposing substrate side via the mirror 6. In the input direction 5 of the video signal, R and B are reflected when they are combined again using a dichroic mirror, so that no image inversion occurs.

A projected image is then obtained by the projection lens 7.

In this embodiment as described above, the input direction of the video signal of the liquid crystal light valve used for the colored light guided to the projection optical system by reflection in the dichroic mirror that combines each color light is the same as the colored light guided to the projection optical system by transmission. By making the input direction of the video signal different from that of the liquid crystal light valve used in the liquid crystal light valve, each incident light can be made to enter from the light shielding layer side. As a result, the contrast ratio decreases due to insufficient retention of the R and E liquid crystal light valves. Furthermore, since the display characteristics of each panel are now the same, color reproducibility is improved, and since the influence of light leakage is reduced, the light source can be made brighter, making it possible to obtain high-luminance images.

[Example 2] This example will be described below based on the drawings. Figure 3 (α
) is a plan view of a liquid crystal light valve with a built-in driver for G, and Fig. 3Cb) is a plan view of a liquid crystal light valve with a built-in driver for R and B. Then, the switching element, gate drive circuit, and source drive circuit of each pixel were formed using polysilicon thin film transistors (TIF'l'), and a TPT substrate 1 for G was obtained.

Next, using an inverted mask of the G photomask, R and B TNT substrates 2 were created.

A counter substrate 3 having a light shielding layer and a common electrode corresponding to each of the TNT substrates for R, B, and G described above is created, and a liquid crystal cell is assembled between each TPT substrate and the counter substrate via a spacer and a gap agent. was enclosed.

Next, it was mounted on the frame substrate 4 by wire bonding and the connector 5 was attached to obtain a liquid crystal light valve with built-in drivers for R, G, and B.

The above-described liquid crystal light valve with built-in R, G, and B drivers was incorporated into the projection display shown in FIG. 2 to create a projection display.

In this embodiment as described above, the output direction of the shift register of the driver is reversed using an inversion mask, and the video signal of the n & light valve used for the colored light guided to the projection optical system by reflection at the dichroic mirror is By changing the input direction of the video signal of the liquid crystal light valve used for the colored light that is guided to the projection optical system by transmission, it is as bright as in Example 1.
A projected image with high contrast colors and excellent color reproducibility can be obtained.

〔Effect of the invention〕

As explained above, the present invention achieves high contrast by reversing the input order of the video signal to the source line of the active matrix liquid crystal light valve used for the color light reflected by the dichroic mirror that combines each color light and the color light transmitted. It is possible to obtain a projected image having excellent color reproducibility. Furthermore, since the light leakage of T7T can be reduced, the light source can be made brighter, and a high-luminance projected image can be obtained.

[Brief explanation of the drawing]

Fig. 1 (α) is a plan view of the G liquid crystal light valve. Fig. 1 (b) is a plan view of the R and B liquid crystal light valves 1... Rigid substrate 2... TNT substrate 3...Counter substrate 4...Flexible substrate 5...Source drive IC 6...Gate drive IC Figure 2 shows a projection type display Optical system configuration diagram of the device 1...
・Halogen lamp with ellipsoidal mirror 2... Lens 3... Dichroic mirror 4... Liquid crystal light valve 5... Video signal input direction 6...・Mirror 7...Projection lens Figure 3 (α) is a plan view of the liquid crystal light valve with a built-in driver for G. Figure 3 Cb') is a plane view of the liquid crystal light valve with a built-in driver for R and B. Figure 1...TFT substrate 2 for G...TII'T substrate 3 for R and B...
Opposite board 4... Frame board 5... Connector and above Applicant Seiko Epson Corporation (α) (b) Figure 1 No.? figure

Claims (1)

[Claims] Using a dichroic mirror, the light from the light source is divided into red, green,
In a projection type display device that separates blue light into each color light, optically switches the color light through three active matrix liquid crystal light valves, combines it again with a dichroic mirror, and forms a projected image with a projection optical system, In the dichroic mirror that combines the colored lights, the input direction of the video signal of the liquid crystal light valve used for the colored light guided to the projection optical system by reflection is the video signal of the liquid crystal light valve used for the colored light guided to the projection optical system by transmission. A projection type display device characterized in that the input direction is different from that of the input direction.