JP3028272B2 - Liquid crystal display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device using a liquid crystal panel having a thin film surface including electric elements such as transistors.

[0002]

2. Description of the Related Art A method of manufacturing a liquid crystal display device by removing a part of a substrate having a thin film including an electric element such as a transistor and using an element substrate having a thin film surface portion made transparent only of the thin film. Is disclosed, for example, in Japanese Patent Application Laid-Open No. 3-194115.

[0003] In such a liquid crystal display device, a driving circuit including transistors and the like is formed on a single crystal silicon SOI substrate, and a liquid crystal cell is formed using the silicon substrate and the transparent substrate. The device configuration capable of transmissive display has been provided by etching the back surface only of the portion to be formed to remove the opaque silicon portion and forming a substantially transparent thin film including the circuit and the like.

The above-mentioned transmission light type liquid crystal display device in which a semiconductor element is formed on a single-crystal Si thin film can operate at a much higher speed than a device in which an element made of polycrystalline Si is formed.

[0005]

The above-mentioned prior art device is
As shown in FIG. 5, a liquid crystal panel 9 is constituted by using a transparent substrate 1 having a color filter layer 2 and a common electrode 3 and a silicon SOI substrate 6 having a thin film 7 including an electric element, and located on the rear surface. It comprises a backlight light source 51 and a protective glass or eyepiece 52 located on the front surface.

However, when the silicon substrate is etched away and the liquid crystal image is viewed from the display section 8 on which the thin film surface section 7a is formed, the etched side 6a of the silicon substrate has a constant inclination, so that it is viewed from the visual side. Part of the incident light 53 is reflected by the etching removal surface 6a, and reaches the viewing side as reflected light. As a result, there is a problem that the liquid crystal image becomes extremely difficult to see.

An object of the present invention is to eliminate the above-mentioned problems in a liquid crystal display device of a transmission light type by removing a portion corresponding to an image display portion of a silicon substrate.

[0008]

In order to achieve the above object, the measures taken in the present invention are as follows:

In a liquid crystal display device using a liquid crystal panel having a thin film surface portion formed by removing a portion corresponding to an image display portion of a silicon substrate on which a thin film including an electric element is formed,

A light shielding plate having an opening which is the same as or smaller than the image display area is provided on the front surface of the thin film surface.

According to the present invention, incident light from the front side (viewing side) of the liquid crystal panel is not irradiated on the silicon substrate removed surface around the image display unit, and the periphery of the image display unit may shine. This prevents the visibility of the liquid crystal image from being significantly improved.

As the light-shielding plate according to the present invention, for example, a non-light-transmitting substrate having the above-mentioned opening or a light-shielding layer having the above-mentioned opening formed on a light-transmitting substrate, etc. Can be used.

The light shielding layer is made of a non-translucent material,
It can be formed by printing or coating.

The light-shielding plate may be either insulating or conductive. If it has conductivity, it is preferable to connect the light-shielding plate to a silicon substrate because the back potential of the silicon substrate can be controlled. Further, the eyepiece itself may be used also as a light shielding plate.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments.

Embodiment 1 FIG. 1 shows a liquid crystal panel and a light shielding plate in a liquid crystal display device of this embodiment, and other components such as a backlight light source are omitted. FIG. 1A is a side sectional view,
FIG. 1B is a diagram viewed from the front of the panel (viewing side).

In FIG. 1A, 1 is a transparent substrate, 2 is a light-shielding layer for shielding light between a color filter layer and a pixel, 3 is a common electrode for applying a voltage to a liquid crystal, 4 is a liquid crystal sealing area, and 5 is a liquid crystal sealing area. It is a liquid crystal, and the sealing region 4 also defines the thickness of the liquid crystal 5. 6 is a silicon SOI substrate whose image display area has been removed and has become transparent, 6a is a removed surface of the silicon substrate,
Reference numeral 7 denotes a thin film provided with an electrode for applying a voltage to the liquid crystal, a transistor, and a driving circuit for each pixel. Reference numeral 7a denotes a thin film surface portion located on the image display unit 8. The liquid crystal panel 9 is constituted by these. Reference numeral 10 denotes a light-shielding plate provided on the front surface of the liquid crystal panel, which characterizes the present invention.
Has an opening 11 slightly smaller than the area of the image display section 8 as shown in FIG.

In this embodiment, the light shielding plate 10 is made of A
A black plate made of BS resin was used.
(Polycarbonate), resin thin plates such as PPS, films such as vinyl chloride and polyethylene, and non-translucent materials such as paper can be used.

The light-shielding plate 10 blocks incident light from the viewing side to the silicon substrate removal surface 6a around the image display section 8, and prevents the inclined removal surface 6a from shining.

The size and shape of the opening 11 of the light-shielding plate 10 are determined in consideration of the installation distance from the silicon substrate 6 and the like.

In this embodiment, the image display section 8 is set to about 14.2.
mm × about 10.6 mm square, about 1 on the same center
By placing the light-shielding plate 10 having a square opening 11 of 3.9 mm × about 10.3 mm at a distance of about 0.7 mm from the silicon substrate 6, a liquid crystal image could be clearly seen.

Embodiment 2 FIG. 2 shows the configuration of the liquid crystal display device of this embodiment. In FIG. 2, the backlight light source and the like are omitted, and FIG.
Those indicated by the same reference numerals as those of the above indicate equivalent members.

In this embodiment, the light shielding plate 1 having the opening 11
Reference numeral 0 denotes an example in which a conductive substrate such as a stainless steel plate or a substrate subjected to a conductive surface treatment is used, and the SOI substrate 6 is electrically connected to the SOI substrate 6 using a conductive adhesive layer 21, and is fixed and positioned. is there.

With such a configuration, the SOI
The substrate potential can be controlled.

Thus, the leakage current due to the operation of the transistors constituting the driving circuit and the peripheral circuit formed around the thin film surface portion 7a of the image display portion is reduced,
This is useful for stabilizing the channel potential of a semiconductor device used for a driver circuit or the like.

In this embodiment, the liquid crystal image was clearly seen as in the first embodiment.

Embodiment 3 FIG. 3 shows the structure of the liquid crystal display device of this embodiment. Also in FIG. 3, the backlight light source and the like are omitted, and those denoted by the same reference numerals as those in FIG. 1 represent equivalent members.

In this embodiment, as the light-shielding plate 10, a light-shielding layer 32 made of a material such as a non-light-transmitting epoxy or acrylic resin or paint is provided on a light-transmitting substrate 31 such as glass. Using a substrate, the SOI substrate 6 and the adhesive layer 33
This is an example of fixing and positioning.

The light shielding layer 32 has an opening at a portion corresponding to the image display area.

In the present embodiment, it is possible to protect the substrate removal surface 6a and the thin film surface portion 7a and prevent foreign substances from entering from outside.

Also, by using a conductive resin mixed with carbon or Ag particles for the light-shielding layer 32 and using a conductive adhesive for the adhesive layer 33, the potential of the SOI substrate 6 can be controlled in the same manner as in the configuration of FIG. Becomes

In order to reinforce the thin film surface portion 7a, it is preferable to fill a space between the SOI substrate 6 and the light shielding plate 10 with a light transmissive filler 34 such as a Si-based resin.

In this embodiment, the liquid crystal image could be clearly seen as in the first embodiment.

Embodiment 4 FIG. 4 shows the structure of the liquid crystal display device of this embodiment. Also in FIG. 4, the backlight light source and the like are omitted, and those denoted by the same reference numerals as those in FIG. 1 represent equivalent members.

In this embodiment, as the light-shielding plate 10, a non-light-transmitting light-shielding layer 32 similar to that of the third embodiment is provided on a light-transmitting base material 41 such as glass serving also as an eyepiece.
0 is an example in which other parts on the optical optical path can be omitted by having a lens effect.

Also in this embodiment, a liquid crystal image could be clearly seen as in the first embodiment.

[0037]

As described above, according to the present invention,
When the liquid crystal display image is visually recognized, the substrate removal surface around the image display unit is prevented from shining with the light incident from the viewing side, so that the liquid crystal image is very easy to see.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a liquid crystal display device according to one embodiment of the present invention.

FIG. 2 is a schematic sectional view of another embodiment of the present invention.

FIG. 3 is a schematic sectional view of another embodiment of the present invention.

FIG. 4 is a schematic sectional view of another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a conventional liquid crystal display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Color filter layer and inter-pixel light shielding layer 3 Common electrode 4 Liquid crystal sealing area 5 Liquid crystal 6 Silicon SOI substrate 7 Thin film 7a Thin film surface part 8 Image display part 8a Silicon substrate removal surface 9 Liquid crystal panel 10 Light shielding plate 11 Opening 21 Conduction Adhesive 31 translucent substrate 32 light-blocking layer 33 adhesive 34 filler 41 translucent substrate 51 backlight light source 52 protective glass or eyepiece 53 incident light 54 reflected light

Claims (4)

(57) [Claims] 1. A liquid crystal display device using a liquid crystal panel having a thin film surface portion formed by removing a portion corresponding to an image display portion of a silicon substrate on which a thin film including an electric element is formed, wherein: A liquid crystal display device, further comprising a light-shielding plate having an opening that is the same as or smaller than the image display area. 2. The liquid crystal display device according to claim 1, wherein the light shielding plate is a non-translucent substrate having an opening. 3. The liquid crystal display device according to claim 1, wherein the light shielding plate is formed by forming a light shielding layer having an opening on a light transmitting substrate. 4. The light shielding plate has conductivity.
3. The liquid crystal display device according to any one of 3.