JP3143608B2 - Projection display device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal device using a liquid crystal panel as an optical shutter and a projection display device. 2. Description of the Related Art A conventional projection display device irradiates a liquid crystal display device 22 with light from a light source 21 as shown in FIG. The image is enlarged and projected by the lens 25. As shown in FIG. 3, a liquid crystal display device 22 is connected to a liquid crystal panel 31 with a wiring tape 32 on which a driving IC is mounted.
It is connected to the. The liquid crystal panel 31 has an effective display area 34
And non-drive area 35, seal area 36, connection terminal area 37
Divided into large. In a liquid crystal panel, polarizing plates are arranged on both sides of the liquid crystal panel in a TN (twisted nematic) system in order to secure the contrast ratio. [0005] However, the above-mentioned prior art has a problem that light from a light source is transmitted in an area other than the effective display area of the liquid crystal display device, and an unnecessary projected image is displayed. This is because the transmitted light from the connection terminal region 37, the non-driving region 35 when the polarization directions of the two polarizing plates are used crossing each other, and the polarization directions of the two polarizing plates are used in parallel. The light transmitted from the seal region 36 in this case is the cause. An object of the present invention is to solve such a problem, and an object of the present invention is to provide a projection display device which does not generate an unnecessary projection image. SUMMARY OF THE INVENTION The present invention provides a projection type projector having a light source, a liquid crystal device for receiving light from the light source, and projection optical means for projecting an image formed by the liquid crystal device. In the display device, the liquid crystal device includes liquid crystal sealed between a pair of substrates, and a light-shielding film disposed in a peripheral area of an effective display area on an inner surface side of one of the pair of substrates and the one substrate. Light-shielding means arranged in a peripheral area of the effective display area on the outer surface side of the seal material, and the end of the light-shielding means on the effective display area side is located inside the end of the sealant on the effective display area side. Along with the light-shielding film, the light-shielding means is disposed so as to have a planar overlap with the light-shielding film and the sealing material. Characterized by a film And FIG. 1 is a main sectional view showing a liquid crystal display device (liquid crystal panel) used in a projection type display device according to the present invention. There is.
Further, a light-shielding film 4 is formed outside the other substrate 3. A manufacturing method will be described by taking a liquid crystal display device using an active matrix substrate as an example. As the active element, there are a thin film transistor, a thin film diode, and the like. However, since the effect of the present invention does not change depending on the presence or absence or type of the active element, an example of the thin film transistor will be described. Thin-film transistors are arranged in a matrix on a transparent substrate, and a polyimide resin is applied to a so-called active matrix substrate on which wiring such as signal lines and timing lines has been applied.
The liquid crystal is aligned by rubbing in a predetermined direction with a cotton cloth or the like. A transparent conductive film is formed on another transparent substrate, and a metal film is further formed. The metal film can be formed of a metal such as Cr or Ni by a vapor deposition method or a plating method. This metal is formed into a predetermined shape by a photo etching method. At this time, at least the metal in the effective display area is removed, and the light-shielding film 1 is formed so as to leave the periphery of the effective display area. After the substrate thus formed was subjected to an alignment process in the same manner as the active matrix substrate, a resin film pattern was formed on a seal region for enclosing liquid crystal by printing or the like on one substrate, and the alignment process was performed.
The liquid crystal 6 is sealed by fixing the resin film pattern while holding a predetermined gap between the substrates, thereby forming a liquid crystal panel. On the active matrix substrate side of this liquid crystal panel, a black light-shielding film 4 is formed on the periphery by printing.
Here, the peripheral part is a connection terminal area, a seal area, and a non-drive area. Since the non-driving region is shielded from light by the light-shielding film 1, it is not necessary to cover the entire area with the light-shielding film 4. The liquid crystal panel is connected to the printed wiring board 7 by a wiring tape 8, and an IC for driving a liquid crystal is often mounted on the wiring tape. Since the connection by the wiring tape is weak in strength, it is generally strengthened by a resin, but a reinforcing plate 9 may be attached in some cases. When the reinforcing plate is made of a light-shielding metal or the like, the light-shielding range is widened. FIG. 4 is a cross-sectional view showing another example.
The light-shielding film 41 formed on the liquid crystal side is not formed in the seal region unlike FIG. When the adhesion between the sealing material (resin film pattern) and the light shielding film is poor, or when the sealing material is a photocurable resin, the light shielding film may not be formed in the sealing region. The opposing substrate 42 and the active matrix substrate 3 are assembled into a panel in the same manner as described above to form a liquid crystal panel. Outer surface of counter substrate 42 (opposite to liquid crystal)
Then, a light shielding film 44 is formed. The light-shielding film 44 may be formed in advance of a metal film by a vapor deposition method or a plating method, or a black light-shielding film may be formed by printing after assembling the panel. The above liquid crystal panel is mounted on a printed wiring board. In the case of FIG. 4, the liquid crystal panel is directly held and fixed on the printed wiring board with a step formed on the printed wiring board. Since the printed wiring board also has a light shielding effect,
The printed wiring board 43 is configured so as to partially overlap the light-shielding region formed by the light-shielding films 41 and 44. The printed wiring board is generally made of a glass epoxy material and has poor light-shielding properties. Therefore, in FIG. 4, a black ink material is applied as a light-shielding film on the printed wiring board. FIG. 5 shows still another example. Except that the light-shielding film 4 in FIG. 1 is not formed, a light-shielding plate 51 is attached to the liquid crystal display in the same manner as in the example of FIG. The light-shielding plate 51 partially overlaps the light-shielding film 1 like the light-shielding film of the previous example, so that light does not leak. The light shielding plate 51 can be made thicker to have the effect of a reinforcing plate. In this case, as shown in FIG. 5, the end surface of the light shielding plate 51 on the effective display area side of the panel is used. It is recommended that the light be inclined so that light is not reflected. As described above, according to the present invention, light outside the effective display area can be completely blocked. In particular, by forming a light-shielding film on the inner surface side of the substrate near the effective display area, light can be shielded with high accuracy. Further, in addition to the light-shielding film on the liquid crystal surface, by forming a light-shielding film on the liquid crystal panel surface so as to at least partially overlap the light-shielding film on the liquid crystal surface, light from the periphery of the display area can be completely shielded, It is possible to realize a projection-type display device capable of obtaining a good image without generating an unnecessary projection image due to leaking light. Furthermore, even if strong light is incident on the liquid crystal device in the projection display device, the end of the light shielding means on the effective display area side is located inside the end of the sealant on the effective display area side,
Light leakage can be prevented by the dual structure of the light shielding film and the light shielding means. Further, since the light shielding film is made of a metal film, the light shielding accuracy can be improved.

[Brief description of the drawings] FIG. 1 is a main cross-sectional view showing a light-shielded liquid crystal display device. FIG. 2 is a schematic view of a projection display device. FIG. 3 is a plan view of a liquid crystal display device. FIG. 4 is a main cross-sectional view showing a light-shielded liquid crystal display device. FIG. 5 is a main cross-sectional view showing a light-shielded liquid crystal display device. [Explanation of symbols] 1, 41 ... light shielding film 5 Seal 7 Printed wiring board 6 Liquid crystal 4,44 ... light shielding film 51 ... light shield plate

Claims (1)

(57) [Claims] A light source, a liquid crystal device that receives light from the light source,
In a projection type display device having projection optical means for projecting an image formed by the liquid crystal device, the liquid crystal device includes liquid crystal sealed between a pair of substrates, and an inner surface of one of the pair of substrates. A light-shielding film disposed in a peripheral area of the effective display area on the side of the side and a light-shielding means disposed in a peripheral area of the effective display area on the outer surface side of the one substrate; The part is located inside the end of the sealing material on the effective display area side and is located more peripherally than the end of the light shielding film on the effective display area side, and the light shielding means is provided between the light shielding film and the sealing material. Wherein the light-shielding film is made of a metal film.