JPH024286A - Liquid crystal projector - Google Patents

Abstract

PURPOSE:To reduce a liquid crystal display device in size and to miniaturize it by scanning stepwise at every scanning stage images corresponding to one scanning position of one-dimensional liquid crystal display device and being irradiated with light from a light source for projection. CONSTITUTION:The title liquid crystal projector is provided with the one- dimensional liquid crystal display device 25 of a horizontal scanning type, which is arranged on the optical axis of the light source 20 for projection, and with scanning means 27A and 27B which scan stepwise in a vertical (or horizontal) direction at every scanning stage images corresponding to one scanning portion of one-dimensional liquid crystal display device 25. Those images are irradiated with light from the light source 20 for projection. Therefore, the one-dimensional liquid crystal display device can be reduced in size in its height direction, thereby miniaturizing the liquid crystal projector. In the one-dimensional liquid crystal display device, the number of picture elements in a vertical (or horizontal) direction becomes unlimited so that the number of picture elements in a lateral (height) direction can be independently increased. The resolution of projected moving images can thereby be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a projection device (or projection device), and particularly to a technique that is effective when applied to a liquid crystal projection device incorporating a liquid crystal display device.

[Conventional technology]

2. Description of the Related Art Projection devices such as over-the-air projectors (OHP) and slide projectors are used for presentations at conferences, lectures, and the like. In this type of projection device, the image projected onto the screen is a still image.

2. Description of the Related Art Recently, there has been an increasing demand for images projected by a projection device to be moving images, and research and development on the subject has been actively conducted. The present inventor is developing a projection device (projection device) that incorporates an active matrix two-dimensional color liquid crystal display device. This projection device mainly includes a projection light source, the liquid crystal display device sequentially arranged on its optical axis, and a projection optical lens. The liquid crystal display device is provided for forming moving images. The optical lens for projection is
The device is configured to project moving images on this liquid crystal display device onto an external screen placed outside the device. This projection device with a built-in liquid crystal display device has the feature that it can be made compact and portable because the size of the liquid crystal display device that forms moving images is very small in the optical axis direction.

Regarding the projection device incorporating this type of liquid crystal display device, see, for example, Niss I Day 87 Digest Section 6, pages 75 to 78.

1987 (SID 87 DIGEST 5ecsi
on 6. pp75-78.1987). Regarding this type of projection device, Eurodisplay '87. Pages 115 and 116, 1987
(EURODISPLAY'87.ppH5-116
．． 1987).

[Problem to be solved by the invention]

The two-dimensional color liquid crystal display device built into the projection device currently being developed by the present inventor has approximately 640 x 480 pixels in order to obtain a resolution that is sufficient for practical use of moving images projected using normal NTSC television signals. It arranges pixels. When using the current processing technology, the minimum processing dimension of the pitch between pixels is 0.06 to 0.07 [mm], so the pixel surface (liquid crystal effective display surface) is 30 [mm] in the height direction.
mm1. 40 [mml in the horizontal direction, 50 [mml] in the diagonal direction
s] size. Since a driving circuit is arranged around the pixel surface, the liquid crystal display device has a size of approximately 60 mm in the height direction and approximately 70 mm in the horizontal direction.

For this reason, the projection device can be made smaller to a certain extent because the size of the liquid crystal display device in the thickness direction (size in the optical axis direction) is small, but the size of the liquid crystal display device in the height direction or horizontal direction is Therefore, there was a problem in that it was not possible to reduce the size of the ear projection device in that direction.

Furthermore, the projection device currently being developed by the present inventor is small and highly portable, and can be carried anywhere. However, depending on the location, there may be no external screen or something equivalent to an external screen such as a white wall. . In such a case, there is a problem in that the projection device cannot project moving images.

Furthermore, the projection device currently being developed by the present inventor is small and has excellent portability as described above, and can be carried anywhere. However, depending on the location where the projection device is carried, the prepared external screen may be a front projection type or an abjection type.

The front projection type external screen is configured so that moving images can be viewed from the projection direction side. The rear projection type external screen is configured so that moving images can be viewed from the back side opposite to the projection direction. For this reason, there is a problem in that the moving image projected by the projection device is reversed by the prepared external screen, making the moving image unsightly.

An object of the present invention is to reduce the size of the liquid crystal display device in the height direction (horizontal scanning direction) or horizontal direction (vertical scanning direction) in a projection device incorporating a liquid crystal display device, thereby achieving miniaturization. The aim is to provide the latest technology.

Another object of the present invention is to provide a technique capable of improving the resolution of a projected moving image in a projection device incorporating the liquid crystal display device.

Another object of the present invention is to provide a technique that can improve manufacturing yield in a projection device incorporating the liquid crystal display device.

Another object of the present invention is to provide a technique that allows a projection device incorporating a liquid crystal display device to project moving images with or without an external screen or an equivalent device.

Another object of the present invention is to provide a technique that can prevent moving images from being reversed depending on the projection method in a projection device incorporating a liquid crystal display device.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

(1) In a liquid crystal projection device, a one-dimensional horizontal scanning type (or vertical scanning type) one-dimensional liquid crystal display device arranged on the optical axis of a projection light source, and a one-dimensional liquid crystal display device that is projected using light from the projection light source. A scanning device is provided that scans an image of one scan of the one-dimensional liquid crystal display device in a vertical direction (or horizontal direction) stepwise for each scan.

(2) In addition to the above-described configuration, the liquid crystal projection device includes a movable screen that is placed at a position for projecting a moving image scanned by the scanning means and that can be avoided from that position.

(3) In addition to the above configuration, the liquid crystal projection device includes means for reversing the scanning direction of the shift register of the one-dimensional liquid crystal display device.

[For production]

According to the above-mentioned means (1), since the size of the one-dimensional liquid crystal display device in the height direction (or lateral direction) is reduced, it is possible to downsize the liquid crystal projection device.

In addition, the one-dimensional liquid crystal display device is not limited by the number of pixels in the vertical direction (or horizontal direction), and the number of pixels in the horizontal direction (or height direction) can be increased independently. Image resolution can be improved.

In addition, the one-dimensional liquid crystal display device is free from restrictions on the number of pixels in the vertical direction (or horizontal direction), and processing precision such as horizontal (or height) pixel size and pitch between pixels can be relaxed. , it is possible to improve the manufacturing yield of one-dimensional liquid crystal display devices.

According to the means (2), in addition to the effect of the above (1), it is possible to avoid the movable screen from the projection position and project a moving image on an external screen, or to project a moving image on an external screen even when there is no external screen. It is possible to project moving images by placing it at a projection position.

According to the means (3), in addition to the effect of the above (2), the video signal line (
Since the scanning direction of the scanning signal line (or scanning signal line) can be reversed, it is possible to prevent the moving image projected on the screen from being reversed.

As a result, it is possible to reduce the unsightliness of moving images caused by the projection method.

Hereinafter, the configuration of the present invention will be explained along with one embodiment.

Note that throughout the description of the embodiments, parts having the same functions are given the same reference numerals, and repeated explanations thereof will be omitted.

〔Example〕

(Example ■) The configuration of a liquid crystal projection device which is Example I of the present invention is shown in Fig. 1 (
2 (schematic cross-sectional view).

As shown in FIGS. 1 and 2, a liquid crystal projection device (liquid crystal projection device) 1 mainly includes a main body 10, a projection light source 20, a one-dimensional liquid crystal display device 25, a projection optical lens 26, and a galvano mirror. (polygon mirror) 27B and a movable screen 29. Liquid crystal display device 25, optical projection lens 26, galvanometer mirror 27B, movable screen 2
Each of 9 has a projection light source 20 on the optical axis of the projection light source 20.
They are arranged sequentially from the side where they are placed.

Although the main body 10 is not limited to this shape, it has a rectangular shape. Since the main body 10 is used as a frame of the liquid crystal projection device 1, it is made of a material that has appropriate hardness and is lightweight, such as an aluminum alloy or a hard resin material.

The projection light source 20 is formed of a light source that has a light amount and wavelength necessary for projection (projection) and does not damage the liquid crystal display device 25 due to heat. The projection light source 20 is formed of, for example, a halogen lamp. Although not limited to this shape, the projection light source 20 has a rod shape (cylindrical shape) so that the size in the height direction is small and it can irradiate light to the entire area in the scanning direction (horizontal scanning direction) of the one-dimensional liquid crystal display device 25. ). As shown in FIG. 1, a light reflecting plate 21 is arranged near the projection light source 20 on the opposite side to the direction facing the liquid crystal display device 25. As shown in FIG. The light reflecting plate 21 is configured to efficiently irradiate the liquid crystal display device 25 with light from the projection light source 20. The light reflecting plate 214 is formed of, for example, a concave mirror.

Between the projection light source 20 and the liquid crystal display device 25, a cylindrical lens 22. The infrared filters 23 are arranged one after another. These are basically made of a glass material, but may be made of a resin material in order to reduce the weight of the liquid crystal projection device 1. The cylindrical lens 22 is
The light from the projection light source 20 can be uniformly irradiated onto the pixel surface of the liquid crystal display device 25, and the size in the height direction can be reduced.

A liquid crystal display device 25 projected with light from a projection light source 20
The moving image is incident on the projection optical lens 26.

The image is folded back by the galvanometer mirror 27B and the movable reflecting mirror 28 and projected onto the movable screen 29.

The projection optical lens 26 is configured to be able to adjust the focus of the moving image when projecting the moving image from the liquid crystal display device 25. In other words, the projection optical lens 26
The focal point of the lens is adjusted by freely moving it in six directions along the optical axis. In particular, as will be described in detail later, the liquid crystal projection device 1 is configured so that moving images can be clearly projected onto each of the built-in movable screen 29 and the external screen (30) disposed outside. The projection optical lens 26 requires a mechanism for adjusting the focus. Further, the projection optical lens 26 may be configured so that a magnification adjustment lens can be added thereto.

The galvanometer mirror 27B is configured to project (reflect) a moving image on the liquid crystal display device 25 from the inside of the main body 10 toward a movable reflecting mirror 28 disposed at one end on the outside. One end of the galvano mirror 27B is connected to a step motor 27A, and the galvano mirror 27B is configured to rotate in the direction of the arrow (or in the direction of the arrow d) by the step motor 27A. Galvano mirror-27B
is configured to vertically scan an image formed by one horizontal scan of the one-dimensional liquid crystal display device 25 stepwise for each scan (scan the surface of the movable reflecting mirror 28). The galvano mirror 27B is composed of an octahedron, and one reflective surface of the octahedron is configured to perform one vertical scan and form one screen. The next reflecting surface of the octahedron is configured to perform one first-order vertical scan to form the next one screen. This galvano mirror 27B is 8
It is not limited to a face, but may be a 2, 4, 6°, 10, etc. polyhedron or a monohedron having one reflective surface. Practically speaking, it is preferable that the galvanometer mirror 27B be a polyhedron, since the operating range of the reflecting surface is small. In this way, the galvanometer mirror 27B incorporates the horizontal scanning type one-dimensional liquid crystal display device 25 into the liquid crystal projection device 1, so that the one-dimensional liquid crystal display device 25 can be scanned in the horizontal direction in order to form a two-dimensional image. It is configured to be able to scan the image formed in the vertical direction.

The movable reflecting mirror 28 is configured to project the image reflected by the galvano mirror 27B onto a movable screen 29 or the like disposed on the other outer end of the main body 10.

The movable reflecting mirror 28, as shown in FIGS. 1 and 2,
It is rotatably supported by a reflecting mirror support stand 28A that moves in the direction of arrow B. The movable reflector 1!28 is configured so that the projection position of the moving image can be adjusted. Figures 1 and 2
As shown in the figure, when projecting a moving image onto a movable screen 29 built into the liquid crystal projection device 1, a movable reflecting mirror 2
8 is set at an angle of about 45 degrees in the direction of arrow B, for example. In addition, as shown in FIG. 3 (schematic cross-sectional view), when the liquid crystal projection device 1 is not projecting, such as when it is stored or carried,
The movable reflecting mirror 28 is housed in the main body 10 so as to be substantially parallel to the bottom surface of the main body 10 (at an angle of 0 degrees). In addition, as shown in FIG. 4 (schematic sectional view), the liquid crystal projection bag w1
When projecting a moving image onto the external screen 30A placed outside on the side of the movable screen 29, the movable reflection! t28 is set at an angle of about 45 degrees in the direction of arrow B, for example. Further, as shown in FIG. 4, when projecting a moving image onto an external screen 30B disposed outside the liquid crystal projection device 1 on the side opposite to the movable screen 29, the movable reflector 28
is set at an angle of approximately 135 degrees in the direction of arrow B, for example. At this time, the movable reflecting mirror 28 is mounted on the reflecting mirror support stand 28A.
The above-mentioned angle can be set by rotating it relative to the angle.

The movable screen 29 has a position on the other end side of the main body 10, which is a position facing the movable reflector 28, and a position where the movable reflector 28 projects a moving image and a position that can be avoided from that position. It is constructed so that it can freely move in the direction of arrow C shown in FIG. As shown in FIGS. 1 and 2, when projecting a moving image, the movable screen 29 is set at an angle of, for example, 70 to 90 degrees in the direction of arrow C (it is set at the projection position of the moving image). ).

Furthermore, as shown in FIGS. 3 and 4, when not projecting a moving image, the movable screen 29 is mounted on the main body 10 so as to be approximately parallel to the bottom surface of the main body 1o (at an angle of 0 degrees). It is stored (avoided from the moving image projection position).

The movable screen 29 is a so-called front projection type in which moving images are viewed from the projection side (direction of arrow F).

It may be constructed using any so-called rear projection type system in which a moving image is viewed from the side opposite to the projection side (in the direction of arrow R). For example, the movable screen 29 is a front projection type, and the external screen 30A is a front projection type or a rear projection type. Front projection movable screen 2
9 is made of, for example, hard metal or resin, and the image projection surface of this movable screen 29 is coated with white or similar paint or a plate-like material in order to make moving images clearer. Furthermore, the movable screen 29 may be made of the same material as the image projection surface, such as resin. Further, the movable screen 29 may be configured as a rear projection type, and the external screen 30A may be configured as a front projection type or a rear projection type. The rear projection type movable screen 29 is made of a material capable of approximating at least the image projection surface, such as glass, resin, or cloth having a light scattering function.

Inside the main body 10 of the liquid crystal projection device 1, there are a cooling fan (not shown), a fan drive transformer 13, and a power supply circuit 14.
, a television circuit 15, etc. are built in, and a lid 11 is detachably attached to the upper opening of the main body 10.

The cooling fan is attached to the main body 10 near the projection light source 20, which is a heat source, and is configured to radiate heat inside the main body 10 to the outside. The cooling fan is driven by a fan drive transformer 13.

The power supply circuit 14 converts external AC power into DC power,
It is configured to supply this DC power to the television circuit 15. The television circuit 15 is connected to the liquid crystal display device 1t25.
, a step motor 27A, and a galvano mirror 27B.

In this way, in the liquid crystal projection device 1, the projection light source 20
By providing (built-in) a movable screen 29 that is disposed at a position where the image of the liquid crystal display device 25 is projected using light from and can be avoided from that position, the movable screen 29 can be avoided from the projection position. to project moving images onto the external screen 30A or 30B, or use the movable screen 2 even when there is no external screen 30A or 30B.
9 can be placed at a projection position to project a moving image. As a result, the liquid crystal projection device 1 is small because it has a built-in liquid crystal display device 25, and can project moving images even when there is no external screen 30A or 30B or an equivalent white wall, making it portable. You can further improve your sexual performance.

Next, the specific structure of the one-dimensional liquid crystal display device 25 built into the liquid crystal projection device 1 will be explained.

This liquid crystal display device 25 is composed of a color one-dimensional liquid crystal display device with a single-panel structure, and one pixel on the pixel surface is
Figure 6 shows a cross section taken along the line ■--■ in Figure 5, and Figure 7 shows the overall layout of the pixel surface of the liquid crystal display device 25 (equivalent circuit). Figure).

As shown in FIGS. 5 and 6, the liquid crystal display device includes a pixel having a thin film transistor TPT and a transparent pixel electrode ITO on the inner surface (liquid crystal side) of a lower transparent glass substrate SUB1. Lower transparent glass substrate SUB
1 has a thickness of about 1.1 [mm], for example.

As shown in FIGS. 5 to 7, each pixel has one scanning signal line (gate signal line or horizontal signal line) GL and two adjacent video signal lines (drain signal line or vertical signal line). )
Within the intersection area with DL (within the area surrounded by each signal line)
It is located in Since the scanning signal mGL is one-dimensional, one signal extends in the column direction. A plurality of video signal lines DL extend in the row direction and are arranged in the column direction.

The thin film transistor TPT of each pixel has three
It is divided into two (plurality) of thin film transistors (divided thin film transistors) TFTI, TFT2, and TFT3. Each of the thin film transistors TPTI to TFT3 has substantially the same size. Each of the divided thin films 1 to transistors TFTI to TFT3 is
Mainly, gate electrode GT, insulating film GI, i-type semiconductor layer AS
, a pair of source electrode SDI and drain electrode SD2.

The gate electrode GT has a T-shape (branched into a T-shape) that projects in the row direction (downward in FIG. 5) from the scanning signal line GL.

In other words, the gate electrode GT is configured to extend substantially parallel to the video signal gDL. Gate electrode GT
are configured to protrude to the formation regions of the thin film transistors TPTI to TFT3, respectively. The gate electrodes GT of each of the thin film transistors TPTI to TPT3 are integrally formed (as a common gate electrode) and connected to the scanning signal line GL. The gate electrode GT is composed of a single-layer first conductive film g1 so as to prevent the growth of a stepped shape as much as possible in the formation region of the thin film transistor TPT. The first conductive film g1 is formed using, for example, a chromium (Cr) film formed by sputtering, and has a thickness of about 1000 [layers].

As shown in FIG. 6, the gate electrode GT is formed to have a larger size than the i-type semiconductor layer AS (as viewed from below) so as to completely cover the i-type semiconductor layer AS.

Since the aforementioned projection light source 20 is attached to the lower side (or upper side) of the lower transparent glass substrate 5UBI, the gate electrode GT blocks the light from the projection light source 20 and prevents the light from reaching the i-type semiconductor layer AS. It is configured so that it is not exposed to radiation. In other words, the gate electrode GT is configured to reduce conductive development caused by light incident on the i-type semiconductor layer As, and improve the off-characteristics of the thin film transistor TPT.

The scanning signal line OL is composed of a composite film including a first conductive film g1 and a second conductive film g2 provided on the first conductive film g1. The first conductive film g1 of the scanning signal line GL is formed in the same manufacturing process as the first conductive film g1 of the gate electrode GT, and is configured integrally. The second conductive film g2 is made of, for example, aluminum (Afl) formed by sputtering.
) film to a thickness of about 2000 to 4000 [people]. The second conductive film g2 is configured to reduce the resistance value of the scanning signal line GL and increase the signal transmission speed (writing characteristics of pixel information).

Further, in the scanning signal line GL, the width of the second conductive film g2 is smaller than the width of the first conductive film g1. In other words, the scanning signal line OL is configured so that the step shape of its side wall can be relaxed, so that the surface of the upper layer of the insulating film G can be flattened.

The insulating film GI is used as a gate insulating film of each of the thin film transistors TPTI to TFT3. The insulating film GI is formed on the gate electrode GT and the scanning signal line GL. The insulating film GI is formed using, for example, a silicon nitride film formed by plasma CVD, and is formed to a film thickness of about 3,000 μm. Used as a channel forming region. Thin film transistor TPTI divided into multiple parts
The i-type semiconductor layers As of the TFTs 3 are formed integrally or independently in one pixel. The i-type semiconductor layer AS is formed of an amorphous silicon film or a polycrystalline silicon film, and is formed to have a thickness of, for example, about 1500 to 2000 nm. As shown in FIG. 5, the i-type semiconductor layer AS is provided to extend between the scanning signal line GL and the video signal line DL (crossover section).

This extended i-type semiconductor layer AS is configured to reduce short circuits between the scanning signal line GL and the video signal line DL at the intersection.

Thin film transistors TPT1-T divided into a plurality of pixels
Each source electrode SDI and drain electrode SD2 of FT3
As shown in FIGS. 5 and 6, the i-type semiconductor layer A
s, and are provided spaced apart from each other. Source electrode SDI
A conductive film do for ohmic contact is provided between each of the drain electrodes SD2 and the i-type semiconductor layer AS.

The conductive film do is formed of, for example, a polycrystalline silicon film doped with P as an impurity, and has a thickness of about 400 [layers]. This conductive film do is an i-type semiconductor layer A.
It can be deposited in the same CVD apparatus as S.

The source electrode SDI and the drain electrode SD2 are each configured so that when the bias polarity of one circuit changes, the source and drain are interchanged in operation. In other words, the thin film transistor TPT is bidirectional like the field effect transistor FET.

Each of the source electrode SDI and drain electrode SD2 is formed by sequentially overlapping a first conductive film d1, a second conductive film d2, and a third conductive film d3 from the lower layer side in contact with the i-type semiconductor layer AS (conductive film do). It is configured.

The first conductive film d1 is a chromium film formed by sputtering, and has a film thickness of 500 to 1000 [people] (in this example, 60
The film thickness is approximately 0 [person]. As the chromium film is formed thicker, the stress increases, so the chromium film should be formed to a thickness not exceeding 2000 mm. The chromium film has good contact with the conductive film do (or the i-type semiconductor layer AS). The chromium film constitutes a so-called barrier layer that prevents aluminum of the second conductive film d2, which will be described later, from diffusing into the i-type semiconductor layer AS. In addition to the chromium film, the first conductive film d1 includes a high melting point metal (Mo, Ti, Ta, W) film, a high melting point metal silicide (MoSi2.TiSi2.TaSi2.
It may be formed using each of the WSi2) films.

The second conductive film d2 is formed using an aluminum film formed by sputtering, and has a thickness of 3000 to 4000 mm (in this embodiment, a thickness of about 3000 mm). The aluminum film has less stress than the chromium film, can be formed thicker, and is configured to reduce the resistance values of the source electrode SDI, drain electrode SD2, and video signal line DL. The second conductive film d2 is configured to increase the operating speed of the thin film transistor TPT and the signal transmission speed of the video signal line DL. In addition to the aluminum film, the second conductive film d2 may be formed of an aluminum film containing silicon (Si) or copper (Cu) as an additive.

The third conductive film d3 is a transparent conductive film (
The film is formed using ITO (Nesa film) with a film thickness of 1000 to 2000 [people] (in this example, a film thickness of about 1200 [people]). This third conductive film d3 constitutes the source electrode SD1, drain electrode SD2, and video signal line DL, and also constitutes the transparent pixel electrode IT○.

First conductive film d1 of source electrode SDI, drain electrode SD
Each of the second conductive films d1 has a larger size on the channel forming region side than the upper second conductive film d2 and the third conductive film d3. The first conductive film d1 can be used even if mask misalignment occurs in the manufacturing process between the first conductive film d1, the second conductive film d2, and the third conductive film d3.
The conductive film d3 is configured to have a larger size than the second and third conductive films d3. Further, the channel forming region side of the first conductive film d1 may be formed on-the-line with the channel forming region sides of the second conductive film d2 and the third conductive film d3.

First conductive film d1 of source electrode SDI. drain electrode SD
Each of the first conductive films d1 of No. 2 is a thin film transistor TPT.
It is configured to define the gate length.

The source electrode SDI is the transparent pixel electrode IT as described above.
Connected to ○. The source electrode SDI is configured along the step shape of the i-type semiconductor layer AS (the step corresponding to the sum of the thickness of the first conductive film g1 and the thickness of the i-type semiconductor layer AS). Ru.

Specifically, the source electrode SDI includes a first conductive film d1 formed along the step shape of the i-type semiconductor layer As, and a transparent pixel electrode ITO formed above the first conductive film d1.
The second conductive film d2 is formed to have a smaller size on the side connected to the second conductive film d2, and the third conductive film d3 is connected to the first conductive film d1 exposed from the second conductive film. The first conductive film d1 of the source electrode SDI has good adhesion to the i-type semiconductor layer AS, and is mainly configured as a barrier layer against diffused substances such as the second conductive film d2. .

The second conductive film d2 of the source electrode SDI is the first conductive film d1
Since the chromium film cannot be formed thickly due to increased stress and cannot overcome the step shape of the i-type semiconductor MAS, the chromium film is configured to overcome the step shape of the i-type semiconductor layer AS.

In other words, step coverage is improved by forming the second conductive film d2 thickly. Since the second conductive film d2 can be formed thickly, it greatly contributes to reducing the resistance value of the source electrode SDI (the same applies to the drain electrode SD2 and the video signal line DL). The third conductive film d3 is the second conductive film d2
Since the step shape caused by the i-type semiconductor layer AS cannot be overcome, the second conductive film d2 is configured to be connected to the exposed first conductive film d1 by reducing its size. The first conductive film d1 and the third conductive film d3 not only have good adhesion but also have a small step shape at the connecting portion between them, so that they can be reliably connected.

The drain electrode SD2 is configured integrally with the video signal line DL, and is formed in the same manufacturing process. The drain electrode SD2 has an L-shape that protrudes in the column direction intersecting the video signal line DL. That is, the drain electrodes SD2 of the thin film transistors TPTI to TFT3 divided into a plurality of pixels are integrally configured and connected to the same video signal line DL.

The transparent pixel electrode ITO is provided for each pixel and constitutes one of the pixel electrodes of the liquid crystal display section. The transparent pixel electrode ITO has three transparent pixel electrodes (divided transparent pixel electrodes ITO1, IrO2, and IT) corresponding to each of the thin film transistors TPTI to TFT3 divided into a plurality of pixels.
It is divided into O3. The transparent pixel electrode ITOI is connected to the source electrode SDI of the thin film transistor TFTI.

The transparent pixel electrode ITO2 is connected to the source electrode SDI of the thin film transistor TFT2. Transparent pixel electrode ITO
3 is connected to the source electrode SDI of the thin film transistor TFT3.

Each of the transparent pixel electrodes ITOI to ITO3 has substantially the same size as each of the thin film transistors TPTI to TFT3. Transparent pixel electrode ITOI~I
Each of TO3 is a thin film transistor TPTI to TFT3.
Since the respective i-type semiconductor layers AS are arranged in a concentrated manner in one place, the planar shape is L-shaped. Note that each of the transparent pixel electrodes ITOI to IT○3 is not limited to an L-shape, and each of the thin film transistors TPTI to TFT3 may be arranged apart from each other along the video signal line DL to have a rectangular planar shape. You can.

In this way, the thin film transistor TPT of the pixel arranged in the intersection area of one scanning signal line OL and two adjacent video signal lines DL is replaced by a plurality of thin film transistors TPTI~
By dividing the pixel into TFT3 and connecting each of the plurality of divided transparent pixel electrodes ITO1 to ITO3 to each of the plurality of divided thin film transistors TPT1 to TFT3, a divided part of the pixel (for example, TFTl) is free from point defects. As a result, the entire pixel is no longer a point defect (T P T 2 and TFT 3 are not point defects).
Point defects in the entire pixel can be reduced.

In other words, a point defect in one of the divided pixels is small compared to the entire area of one pixel (in the case of this example, the area is one-third of the pixel), so it is difficult to see the point defect. can do. Further, by configuring each of the divided transparent pixel electrodes TOI to IT○3 in the pixel to have substantially the same size, the area of point defects within the pixel can be made uniform.

In particular, the liquid crystal projection device 1 displays moving images on the liquid crystal display device 25 through a projection optical lens 26. Since the image is magnified and projected through the galvanometer mirror 27B and the movable reflecting mirror 28, each pixel arranged on the pixel plane is magnified, making point defects very noticeable.

Therefore, by incorporating the liquid crystal display device 25 in which each pixel is divided into a plurality of parts as described above into the liquid crystal projection device 1,
Even if a point defect occurs in a part of the pixel, most of the pixels can be turned on, so that the point defect can be made difficult to see in the enlarged moving image that is projected.

A protective film PSVI is provided over the thin film transistor TPT and the transparent pixel electrode ITO, as shown in FIG. The protective film PSVI is mainly used for thin film transistor TPT.
The material is formed to protect the material from moisture, etc., so use one that is highly transparent and has good moisture resistance. Protective film PSV
I is formed of, for example, a silicon oxide film or a silicon nitride film formed by plasma CVD, and is formed to have a thickness of about 8000 [layers].

A shielding film LS is provided above the protective film PSVI on the thin film transistor TFT to prevent external light from entering the i-type semiconductor layer AS used as a channel formation region. As shown in FIG. 5, the shielding film LS is configured within a region surrounded by a dotted line. The shielding film LS is formed of, for example, an aluminum film or a chromium film formed by sputtering, which has a high shielding property against light, and is formed to have a thickness of about 1000 [layers].

The thin film transistor TPT is configured such that when a positive bias is applied to the gate electrode GT, the channel resistance between the source and drain becomes small, and when the bias is reduced to zero, the channel resistance becomes large. In other words, the thin film transistor TPT is configured to control the voltage applied to the transparent pixel electrode IT○.

The liquid crystal LC is defined and enclosed by a lower alignment film ○RII and an upper alignment film 0RI2 that set the orientation of liquid crystal molecules in a space formed between a lower transparent glass substrate SUB1 and an upper transparent glass substrate 5UB2. ing.

The lower alignment film 0RII is formed on the protective film PSVI on the lower transparent glass substrate 5UBl side.

On the inner surface (liquid crystal side) of the upper transparent glass substrate 5UB2, a color filter FIL, a protective film PSV2, a common transparent pixel electrode (COM) ITO, and the upper alignment film 0RI2 are disposed.
are sequentially stacked.

The common transparent pixel electrode IT○ is connected to the lower transparent glass substrate 5.
It faces the transparent pixel electrode ITO provided for each pixel on the UBI side and is configured integrally with another adjacent common transparent pixel electrode IT○. A common voltage Vcom is applied to this common transparent pixel electrode ITO. The common voltage Vcom is an intermediate potential between the low-level drive voltage V d min and the high-level drive voltage V d max applied to the video signal line DL.

The color filter FIL is configured by coloring a dyed base material made of a resin material such as acrylic resin with a dye.

As shown in FIG. 8 (a plan view of the pixel surface), the color filter FIL is arranged for each pixel at a position facing the pixel, and is colored differently for each pixel. That is, like the pixels, the color filter FIL is configured within the intersection area of one scanning signal line GL and two adjacent video signal lines DL. Each pixel is divided into a plurality of parts as described above within each predetermined color filter of the color filter FIL.

Color filter FIL can be formed as follows. First, a dyed base material is formed on the surface of the upper transparent glass substrate 5UB2, and the dyed base material other than the red filter forming area is removed using photolithography technology. Thereafter, the dyed base material is dyed with a red dye and subjected to a fixing treatment to form a red filter R. next.

A green filter G and a blue filter B are sequentially formed by performing similar steps.

The protective film PSV2 is provided to prevent the dyes used to dye the color filter FIL into different colors from leaking into the liquid crystal LC. The protective film PS2 is made of a transparent resin material such as acrylic resin or epoxy resin.

This liquid crystal display device 25 has a lower transparent glass substrate 5UBI.
The layers on the side and the upper transparent glass substrate 5UB2 side are formed separately, and then the upper and lower transparent glass substrates 5UBI and 5U are formed separately.
It is assembled by overlapping B2 and sealing liquid crystal LC between them.

As shown in FIGS. 7 and 8, each pixel on the pixel surface (liquid crystal display section) of the liquid crystal display device 25 is arranged in plurality in the same column direction as the direction in which the scanning signal line GL extends, and is arranged in one pixel column. It consists of In other words, the liquid crystal display device 25 has a one-dimensional structure in which pixels are arranged in one column (horizontal direction).

XiG, Xi+IG, . . . shown in FIG. 7 are video signal lines DL connected to the pixels in which the green filter G is formed.
It is. XiB, Xi+IB,... is blue filter B
This is a video signal line DL connected to a pixel in which a pixel is formed.

Xi+IR, Xi+2R, . . . are video signal lines DL connected to pixels in which red filters R are formed. These video signal lines DL are connected to a video signal drive circuit HD and are driven (selected) by this video signal drive circuit HD. The video signal drive circuit HD receives the video signal v1°to and the horizontal synchronizing signal H□ from the television circuit 15 built into the liquid crystal projection device 1 shown in FIG. is input to the video signal line D in synchronization with the scanning of the horizontal shift register H8R.
It is configured to sequentially drive L in the column direction.

The scanning signal line GL shown in FIG. 7 is configured to simultaneously select each pixel. The scanning signal line GL is connected to a scanning signal line drive circuit VD. The scanning signal line drive circuit VD receives the vertical synchronization signal V from the television circuit 15.

. is input to drive the scanning signal line GL. The scanning signal line drive circuit VD is configured to drive the scanning signal line GL every horizontal scan of the video signal line DL in the video signal drive circuit HD (or always).

The vertical synchronizing signal vfz-0 from the television circuit 15 is also input to the frequency dividing circuit 15A. The frequency dividing circuit 15A is configured to control the rotation of the galvano mirror 27B with a step motor 27A interposed therebetween. In other words, the frequency dividing circuit 15A is configured to control the rotation angle of the step motor 27A according to the number of reflective surfaces that the galvano mirror 27B has. For example, when the galvanometer mirror 27B is configured as an octahedron, the frequency dividing circuit 15A rotates the step motor 27 so that it rotates 1/8 to form one screen.
It is configured to control A.

From the television circuit 15 to the horizontal shift register H8R
A video signal V, which is input to. 6° is the horizontal shift register H5 with the video signal changeover switch vSW interposed.
It is configured to be input to one end (right side) or the other end (left side) of R. In other words, horizontal shift register H8R
is structured in a bidirectional manner. The video signal changeover switch vSW is controlled by a microswitch MSW with a flip-flop circuit FF interposed therebetween. The microswitch MSW is controlled manually or automatically in conjunction with the operation of the movable screen 29 or the like.

For example, when the movable screen 29 of the liquid crystal projection device 1 is configured as a front projection type and a moving image of the liquid crystal display device 25 is projected onto the movable screen 29, the video signal V□. 5o is input to one end of the horizontal shift register H8H. This horizontal shift register H3R
can project a predetermined moving image onto the movable screen 29 by driving the video signal line DL from the left side to the right side via the video signal drive circuit HD. On the other hand, this liquid crystal projection device 1 has a rear projection type external screen 3.
When projecting a moving image from the liquid crystal display device 25 on 0A, the left and right sides of the moving image are reversed, so the video signal changeover switch vSW is activated by turning on the microswitch MSW.
The video signal v1゜6゜ is transferred to the horizontal shift register H5R.
input to the other end. This horizontal shift register H8
R drives the video signal line DL from the right side to the left side via the video signal drive circuit HD, and can project a moving image whose left and right sides match the moving image projected on the movable screen 29 onto the external screen 30A. can.

Furthermore, if the moving image projected on the liquid crystal display device 25 of the liquid crystal projection device 1 is reversed vertically, the vertical scanning direction can be changed by, for example, reversing the rotational direction of the step motor 27A and reversing the galvano mirror 27B. This makes it possible to prevent the moving image from being flipped vertically. To reverse the rotational direction of the step motor 27A, a changeover switch may be provided as described above.

In this way, in the liquid crystal projection device 1, the projection light source 20
A one-dimensional liquid crystal display device 25 of a horizontal scanning type arranged on the optical axis of Scanning means for scanning vertically in stages (mainly frequency dividing circuit 15A, step motor 27A, and galvano mirror)
27B), the size of the one-dimensional liquid crystal display device 25 in the height direction can be reduced by not arranging the images in the vertical direction, so that the size can be reduced.

Furthermore, since the one-dimensional liquid crystal display device 25 is not limited by the number of pixels in the vertical direction and can increase the number of pixels in the horizontal scanning direction, the resolution of the projected moving image can be improved.

In addition, the one-dimensional liquid crystal display device 25 is not limited by the number of pixels in the vertical direction, and processing accuracy such as the pixel size in the horizontal scanning direction and the pitch between pixels can be relaxed, so that the one-dimensional liquid crystal display device 25 can be manufactured. The above yield can be improved.

Further, a liquid crystal display device 2 built in the liquid crystal projection device 1
By providing a means for reversing the scanning direction of the horizontal shift register H8R No. 5 (making it bidirectional), the scanning direction of the video signal line DL of the liquid crystal display device 25 can be changed during front projection and rear projection. Since the moving image can be reversed, it is possible to prevent the moving image projected on the screen from being reversed.

The central part of FIG. 6 shows a cross section of one pixel portion of the liquid crystal display device 25, while the left side shows a cross section of the left edge portion of the transparent glass substrates 5UBI and 5UB2 where external lead wiring is present. . On the right is a transparent glass substrate SUB
1 and 5UB2, a cross section of the right edge portion where no external lead wiring is present is shown.

The sealing materials SL shown on the left and right sides of FIG. 6 are configured to seal the liquid crystal LC, and are attached to the transparent glass substrates SUB 1 and 5 excluding the liquid crystal sealing opening (not shown).
It is formed along the entire edge of UB2. The sealing material SL is made of, for example, epoxy resin.

The common transparent pixel electrode ITO on the upper transparent glass substrate 5UB2 side is at least at one location.

The lower transparent glass substrate 5U is made of silver paste material SIL.
It is connected to the external lead wiring formed on the BI side. This external lead wiring is formed in the same manufacturing process as each of the gate electrode GT, source electrode SDI, and drain electrode SD2 described above.

The alignment films 0RII and ○RI2, transparent pixel electrode ITO
1 common transparent pixel electrode ITO 1 protective film PSv1 and PSV
2. Each layer of the insulating film GI is formed inside the sealing material SL. The polarizing plate POL has a lower transparent glass substrate SUB
1. Formed on each outer surface of the upper transparent glass substrate 5UB2.

(Embodiment 2) This embodiment 2 is a second embodiment of the present invention in which scanning of the liquid crystal projection device in the vertical direction was performed by an optical deflector.

FIG. 9 shows the configuration of a liquid crystal projection device which is Embodiment ① of the present invention.
Schematic sectional view).

As shown in FIG. 9, the liquid crystal projection device 1 includes an optical deflector 3 between a one-dimensional liquid crystal display device 25 and a projection optical lens 26.
1 is provided. The optical deflector 31 is configured to change the refractive index of light by applying a voltage, and is configured to vertically scan an image formed by horizontal scanning of the one-dimensional liquid crystal display device 25. ing.

A fixed reflecting mirror 27 is provided between the projection optical lens 26 and the movable reflecting mirror 28. The fixed reflecting mirror 27 is configured to project the moving image formed by the one-dimensional liquid crystal display device 25 and the optical deflector 31 onto the movable screen 29, external screens 30A, 30B, etc. via the movable reflecting mirror 28. has been done.

The liquid crystal projection device 1 incorporating the one-dimensional liquid crystal display bag [25] and the optical deflector 31 can achieve substantially the same effects as in the embodiment I.
27B has mechanical vibrations due to rotation, but the vertical scanning means consisting of the optical deflector 31 does not substantially generate such vibrations, so the optical deflector 31 is built in. The liquid crystal projection device 1 can obtain effects such as fewer failures caused by mechanical vibrations.

Although the invention made by the present inventor has been specifically described above based on the above embodiments, the present invention is not limited to the above embodiments, and can be modified in various ways without departing from the gist thereof.

For example, the liquid crystal projection device is constructed of a horizontal scanning type one-dimensional liquid crystal display device with a high driving frequency, but the present invention includes a vertical scanning type one-dimensional liquid crystal display device and a liquid crystal projection device incorporating a horizontal scanning means. may be configured.

Further, the present invention provides a thin film transistor TP provided for each pixel arranged in the horizontal direction of the one-dimensional liquid crystal display device.
The one-dimensional liquid crystal display device may be configured as a so-called simple matrix type by eliminating T. In this case, in the manufacturing process of the liquid crystal display device, the manufacturing yield can be improved by the amount corresponding to the thin film transistor TPT.

〔Effect of the invention〕

A brief explanation of the effects of one representative invention among the inventions disclosed in this application is as follows.

In the liquid crystal projection device, the size of the liquid crystal display device can be reduced and miniaturization can be achieved.

Furthermore, in addition to the above effects, the liquid crystal projection device can project moving images even when there is no external screen or equivalent.

In addition to the above effects, the liquid crystal projection device can prevent image inversion caused by front projection, rear projection, or other projection methods.

[Brief explanation of the drawing]

Figure 1 is an example of the present invention! FIG. 2 to FIG. 4 are schematic cross-sectional views of the liquid crystal projection device. FIG. 5 is a plan view of a main part showing one pixel on the pixel surface of the liquid crystal display device built into the liquid crystal projection device, and FIG. 6 is a cross-sectional view taken along the line VI-VI shown in FIG. 5. . FIG. 7 is an equivalent circuit diagram of the pixel surface of the liquid crystal display device, FIG. 8 is a plan view of the pixel surface of the liquid crystal display device, and FIG. It is a schematic sectional view. In the figure, 1...Liquid crystal projection device, 14...Power supply circuit, 1
5...TV circuit, 15A...divider circuit, 20...
・Projection light source, 22... Cylindrical lens, 23
...Infrared filter. 25... One-dimensional liquid crystal display device, 26... Optical lens for projection, 27A... Step motor, 27B... Galvano mirror 27... Fixed reflector, 28... Movable reflector, 29...Movable screen, 30A, 30
B...External screen, 31...Light deflector, H8R
...shift register, HD...video signal drive circuit,
VD...Scanning signal line drive circuit, VSW...Video signal changeover switch, MSW...Micro switch, GL
...Scanning signal line, DL...Video signal line, GT...
Gate electrode, AS...i-type semiconductor layer, SD...source electrode or drain electrode, TPT...thin film transistor, ITO...transparent pixel electrode.

Claims (1)

[Claims] 1. A projection light source, a horizontal scanning type or vertical scanning type one-dimensional liquid crystal display device arranged on the optical axis of the projection light source, and a light emitted from the projection light source. 1. A liquid crystal projection device comprising: scanning means for scanning one scanning image of a one-dimensional liquid crystal display device to be projected in a vertical or horizontal direction stepwise for each scanning. 2. The scanning means for scanning one scan of the image of the one-dimensional liquid crystal display device in the vertical or horizontal direction stepwise for each scan is controlled in synchronization with the scanning of the one-dimensional liquid crystal display device. 2. The liquid crystal projection device according to claim 1, comprising a motor and a galvanometer mirror driven by the motor. 3. The scanning means for scanning an image of one scan of the one-dimensional liquid crystal display device in a vertical or horizontal direction stepwise for each scan includes a light beam controlled in synchronization with the scanning of the one-dimensional liquid crystal display device. 2. The liquid crystal projection device according to claim 1, wherein the liquid crystal projection device comprises a deflector. 4. A projection light source, a horizontal scanning type or vertical scanning type one-dimensional liquid crystal display device arranged on the optical axis of the projection light source, and a one-dimensional liquid crystal display device projected by the light from the projection light source. a scanning means for scanning one scanning image of a display device stepwise in the vertical or horizontal direction for each scanning; and a scanning means arranged at a position to project the scanned moving image and capable of being avoided from that position. A liquid crystal projection device characterized by comprising a movable screen. 5. The liquid crystal projection device according to claim 1 or 4, wherein the one-dimensional liquid crystal display device includes means for reversing the scanning direction of the shift register.