JP2004252335A - Projection type display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection type display device that can easily and surely shield a driver circuit mounted on a film from a light source light in a projection type display device employing a COF (Chip On Film) technique. <P>SOLUTION: The projection type display device is equipped with a light source 2, an light modulating device 23 which modulates the light emitted by the light source 2, and a projecting device which projects the light modulated by the light modulating device 23, and further equipped with a control board 40 where a control circuit 41 for controlling the light modulating device 23 is mounted. The control substrate 40 and light modulating device 23 are connected by a flexible substrate 43 on which a semiconductor integrated circuit 42 for driving the light modulating device 23 is mounted. The display device is characterised in that the semiconductor integrated circuit 42 is arranged in a recessed part 47 of the control substrate 40. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a projection display device, and more particularly, to a projection display device including a light modulation device employing a COF (Chip On Film) technology.
[0002]
[Prior art]
2. Description of the Related Art In recent years, the development of information devices has been remarkable, and the demand for thin display devices with high resolution, low power consumption and high power has been increased, and research and development have been promoted. Among them, a liquid crystal display device is expected to be a display device that can electrically control the arrangement of liquid crystal molecules and change optical characteristics, and can meet the above needs.
[0003]
By the way, a COF (Chip On Film) technology in which a driver circuit for driving a liquid crystal display device is packaged and mounted on a film connected to the liquid crystal display device as a technology responding to recent demands for a lighter, thinner and smaller display device. Are known. Such a COF technique can reduce the size and size of the device, but when light is applied to a driver circuit mounted on a film, photovoltaic power is generated, which may cause a malfunction in the liquid crystal display device. There is. For example, Japanese Patent Application Laid-Open Publication No. HEI 11-163873 discloses a technique of attaching a light-shielding tape for shielding light onto a driver circuit or forming a light-shielding pattern on the driver circuit.
[0004]
[Patent Document 1]
JP 2001-154216 A [0005]
[Problems to be solved by the invention]
Although the generation of photovoltaic power in the driver circuit can be suppressed by the technique described in Patent Document 1, for example, forming a light-shielding pattern on the driver circuit is very time-consuming. In particular, when a liquid crystal display device is used as a light modulator (liquid crystal light valve) of a projection display device, the projection display device has a higher light source energy than a direct-view display device, so that the light shielding performance is further improved. Technology is desired.
[0006]
The present invention has been made in order to solve the above-mentioned problems, and for a projection display device employing the above-described COF technology, a driver circuit mounted on a film can be easily and reliably converted from a light source light. It is an object of the present invention to provide a projection display device capable of blocking light.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a projection display device according to the present invention includes a light source, a light modulation device for modulating light emitted from the light source, and a projection device for projecting light modulated by the light modulation device. A control substrate on which a control circuit for controlling the light modulation device is mounted; a flexible substrate connecting the control substrate and the light modulation device; A semiconductor integrated circuit mounted on a substrate for driving the light modulation device, wherein the control substrate is arranged such that one plate surface faces an optical path from the light source to the light modulation device. On the other hand, the semiconductor integrated circuit is provided in a light shielding portion formed on a plate surface of the control substrate opposite to the optical path.
[0008]
According to such a projection display device, the semiconductor integrated circuit mounted on the flexible substrate is shielded from light by the control substrate on which the control circuit for controlling the light modulation device is mounted, and the optical path of the substrate is controlled. Also, light is shielded from the light source by the light-shielding portion formed on the plate surface on the opposite side, so that the generation of photoelectromotive force in the semiconductor integrated circuit can be prevented or suppressed. In particular, in a projection type display device, a high-energy light source such as a metal halide lamp, an ultra-high pressure mercury lamp, or a halogen lamp is often used as the light source light. By adopting the configuration of the present invention, such a high-energy light source is used. It is possible to exhibit light-shielding performance even with respect to the above light.
[0009]
Specifically, it is preferable that the light source and the semiconductor integrated circuit are disposed at opposite positions via the control board. That is, while the light source is provided on the first plate surface side of the control board, the semiconductor integrated circuit is provided on the second plate surface side opposite thereto, so that the semiconductor integrated circuit can be further removed from the light source. It is possible to reliably shield light. As described above, in the projection display device of the present invention, the semiconductor integrated circuit is mounted on the flexible substrate, and is disposed between the flexible substrate and the control substrate. By arranging it inside the unit, light irradiation on the semiconductor integrated circuit is prevented.
[0010]
The light-shielding portion applied to the projection display device of the present invention preferably has at least a structure for blocking light from a light source, and includes, for example, a concave portion formed on a plate surface opposite to an optical path. In this case, a semiconductor integrated circuit can be provided inside the concave portion. Alternatively, it is also possible to adopt a structure including a convex wall portion formed on the plate surface opposite to the optical path. In this case, the semiconductor integrated circuit is disposed inside the convex wall portion as viewed from the light source. Can be set up. Note that it is also possible to adopt a configuration in which a concave portion and a convex wall portion are combined, and in this case, if the semiconductor integrated circuit is provided inside the concave portion, the semiconductor integrated circuit can be more reliably shielded from light. It becomes possible.
[0011]
More specifically, the control board is provided with an insertion hole through which the flexible board can be inserted, and one end of the flexible board is connected to the light modulation device on the optical path side of the control board. On the other hand, the control board is inserted through the insertion hole of the control board on the opposite side of the optical path from the optical path, and the other end is connected to the control board on the plate surface opposite to the optical path. Can be. With such a configuration, the semiconductor integrated circuit is more reliably shielded from the light source.
[0012]
In the projection display device according to the aspect of the invention, it is preferable that the control substrate is formed of a resin-based light-shielding substrate, and the control circuit is mounted on a plate surface opposite to the optical path. Further, the semiconductor integrated circuit can be constituted by a packaged semiconductor chip. In this case, the projection display device of the present invention can be further reduced in weight and thickness. Further, the flexible substrate plays a role of electrically connecting the light modulation device and the control circuit, and may be configured by a laminate of a resin thin film such as a polyimide and a conductive thin film such as a copper foil. Can be.
[0013]
The operation of the light modulation device is controlled by a control circuit. However, the semiconductor integrated circuit mounted on the flexible substrate is used to drive the light modulation device based on a control signal from the control circuit. It plays a role of appropriately transmitting the drive signal. Here, as a light modulation device suitable for the projection type display device of the present invention, for example, a liquid crystal light valve composed of a liquid crystal device can be exemplified.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, a projection type liquid crystal display device which is an example of the projection type display device of the present invention will be described with reference to FIG. The projection type liquid crystal display device 30 shown in FIG. 1 is a three-plate type projection type color liquid crystal display device having a transmission type liquid crystal light valve for each of different colors of R (red), G (green), and B (blue). is there.
[0015]
FIG. 1 is a schematic configuration diagram showing a projection type liquid crystal display device 30 according to the first embodiment, in which reference numeral 1 denotes an illumination device, 2 denotes a light source, 3 and 4 denote fly-eye lenses (uniform illumination means), 5d is a polarization conversion device, 13 and 14 are dichroic mirrors (color separation means), 15, 16, and 17 are reflection mirrors, 22, 23, and 24 are liquid crystal light valves (light modulation devices), 25 is a cross dichroic prism, and 26 is a cross dichroic prism. 3 shows a projection lens (projection device).
[0016]
Illumination device 1 in the present embodiment is mainly configured of light source 2, fly-eye lenses 3, 4, and polarization conversion device 5d. The light source 2 mainly includes a lamp 7 such as a high-pressure mercury lamp and a reflector 8 that reflects light from the lamp 7. Further, as uniform illumination means for uniformizing the illuminance distribution of the light source light on the irradiation surfaces of the liquid crystal light valves 22, 23, 24, a first fly-eye lens 3 and a second fly-eye lens 4 are sequentially installed from the light source 2 side. Have been. Each of the fly-eye lenses 3 and 4 is composed of a plurality of (for example, 6 × 8) lenses 9 and 10 in the present embodiment, and converts the illuminance distribution of the light emitted from the light source 2 to the liquid crystal light valves 22 and 23. , 24 function as uniform illumination means for uniformizing the light irradiation surfaces. The light emitted from the light source 2 is emitted from the uniform illumination means to the polarization converter 5d.
[0017]
The polarization converter 5d includes a polarization beam splitter array (PBS array) provided on the uniform illumination means side and a half-wave plate array provided on the dichroic mirror 13 side. The polarization converter 5d is provided between the uniform illumination means and the dichroic mirror 13.
[0018]
The configuration of the subsequent stage of the lighting device 1 will be described below together with the operation of each component.
The blue / green light reflecting dichroic mirror 13 transmits the red light LR of the light flux from the light source 2 and reflects the blue light LB and the green light LG. The red light LR transmitted through the dichroic mirror 13 is reflected by the reflection mirror 17 and enters the red light liquid crystal light valve 22.
[0019]
On the other hand, among the color lights reflected by the dichroic mirror 13, the green light LG is reflected by the dichroic mirror 14 for reflecting green light and is incident on the liquid crystal light valve 23 for green light. Further, the blue light LB also passes through the dichroic mirror 14, passes through a relay system 21 including a relay lens 18, a reflection mirror 15, a relay lens 19, a reflection mirror 16, and a relay lens 20, and is incident on a blue light liquid crystal light valve 24. You.
[0020]
The three color lights modulated by the liquid crystal light valves 22, 23, and 24 are incident on the cross dichroic prism 25. This prism has four right-angle prisms attached to each other, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface. The three color lights are combined by these dielectric multilayer films to form light representing a color image. The synthesized light is projected on a screen 27 by a projection lens 26 which is a projection optical system, and an enlarged image is displayed.
[0021]
Here, in the projection type liquid crystal display device 30 of the present embodiment, the control board 40 on which the control circuit for controlling the liquid crystal light valves 22, 23, 24 is mounted includes the lighting device 1 and the liquid crystal light valves 22, 23, 23. 24, the projection lens 26 and the like. The control board 40 is electrically connected to the liquid crystal light valves 22, 23, and 24. Specifically, a flexible film member (flexible board) formed by laminating a resin film and a copper foil. Connected through.
[0022]
FIG. 2 schematically shows a cross section taken along line AA ′ of FIG. As described above, the control board 40 is disposed such that one plate surface 51 faces the optical path from the light source 2 to the liquid crystal light valve 23 (22, 24). On the other hand, the control circuit 41 is mounted on the plate surface 52 of the control board 410 on the side opposite to the optical path, and the above-mentioned film member 43 is connected to the connector 44 of the control circuit 41. The control board 40 has an insertion hole 45 through which the film member 43 can be inserted.
[0023]
One end of the film member 43 is connected to the liquid crystal light valve 23 (22, 24). Connected. A driver IC chip 42 for driving the liquid crystal light valve 23 (22, 24) is mounted on the film member 43, and the driver circuit is not directly provided on the substrate constituting the liquid crystal light valve 23 (22, 24). It is configured.
[0024]
Here, in the present embodiment, the driver IC chip 42 is mounted on the film member 43 such that the driver IC chip 42 is located on the plate surface 52 side opposite to the optical path via the control board 40. A recess 47 is formed in the plate surface 52 of the control board 40 opposite to the optical path, and at least a part of the driver IC chip 42 is inserted into the recess 47. Therefore, the control board 40 functions as a light-shielding plate, and the recess 47 also functions as a light-shielding member, so that light from the light source 2 is shielded from the driver IC chip 42 with high efficiency. By shielding the driver IC chip 42 from light with the control board 40 and the recess 47 in this way, it is possible to prevent or suppress the generation of photovoltaic power in the driver IC chip 42, and to prevent the occurrence of display defects. Becomes possible.
[0025]
The control circuit 41 constitutes a main control section that controls the operation of the liquid crystal light valve 23 (22, 24). The driver IC chip 42 controls the liquid crystal light valve 23 (22, 24) based on a control signal from the control circuit 41. , 24) are appropriately transmitted. Further, a polarizing plate can be provided on each of the light incident surface and the light emitting surface of the liquid crystal light valve 23 (22, 24), and transmission of ultraviolet light and infrared light is cut on the light source side of the polarizing plate on the incident side. A UV-IR filter may be provided.
[0026]
Further, in the present embodiment, in order to shield the driver IC chip 42 from light on the control board 40, a concave portion 47 as shown in FIG. 2 is formed on the control board 40 as a light shielding member. It is also possible to constitute a light shielding member by such a convex portion (convex wall portion) 46. In this case, the driver IC chip 42 is disposed inside the projection 46 as viewed from the light source 2 so that at least the light from the light source 2 is blocked by the projection 46. If the convex portion 46 is formed in an annular shape and the driver IC chip 42 is disposed inside the annular shape, the light shielding effect of the convex portion 46 is further enhanced.
[0027]
[Second embodiment]
FIG. 4 is a schematic configuration diagram illustrating a projection-type liquid crystal display device 30c according to the second embodiment. The difference between the projection type liquid crystal display device 30c of the second embodiment and the projection type liquid crystal display device 30 of the first embodiment shown in FIG. 1 is that the illumination device 1 and the illumination device 1 in the first embodiment are different. Dichroic mirrors (color separation means) 13 and 14 for separating the light emitted from the lens into a plurality of color lights, a relay lens 17 and a relay system 21 are provided. The point is that light sources 2R, 2G, and 2B that can emit light are provided.
[0028]
The light source 2R includes a lamp 7R that emits red light LR, and a reflector 8 that reflects the light of the lamp 7R. The light source 2G includes a lamp 7G that emits green light LG and a reflector 8 that reflects the light of the lamp 7G. The light source 2B further emits a lamp 7B that emits blue light LB and a light of the lamp 7B. And a reflector 8 that reflects light. Each of the lamps 7R, 7G, and 7B includes a light-emitting diode (LED), an organic electroluminescent element (organic EL element), an inorganic electroluminescent element (inorganic EL element), and the like.
[0029]
The light sources 2R, 2G, and 2B are provided corresponding to the liquid crystal light valves (light modulation devices) 22, 23, and 24, and the red light LR emitted from the light source 2R enters the red liquid crystal light valve 22. Modulated. The green light LG emitted from the light source 2G enters the green light liquid crystal light valve 23 and is modulated. Further, the blue light LB emitted from the light source 2B enters the blue light liquid crystal light valve 24, where it is modulated.
[0030]
The three color lights modulated by the liquid crystal light valves 22, 23, and 24 are incident on the cross dichroic prism 25, where the three color lights are combined to form light representing a color image. The synthesized light is projected on a screen 27 by a projection lens 26 which is a projection optical system, and an enlarged image is displayed.
[0031]
Also in the second embodiment, similarly to the first embodiment, the control board 40 on which the control circuit for controlling the liquid crystal light valves 22, 23, and 24 is mounted is similar to the light source 2R, 2G as in FIG. , 2B, the liquid crystal light valves 22, 23, 24, the projection lens 26, and the like. In addition, a concave portion 47 (see FIG. 2) and / or a convex portion 46 (see FIG. 3) are formed as a light shielding member on a surface of the control substrate 40 that does not face the optical path.
[0032]
The liquid crystal light valves 22, 23, and 24 are mounted on a fill member 43 that connects the liquid crystal light valves 22, 23, and 24 to the control circuit 41, inside the light shielding member, that is, at a position where the light shielding member is shadowed when viewed from the light sources 2R, 2G, and 2B. A driver IC chip 42 is provided. Therefore, also in this case, the driver IC chip 42 is shielded from light from the light sources 2R, 2G, and 2B. As a result, the generation of photoelectromotive force in the driver IC chip 42 is prevented or suppressed, and a projection-type liquid crystal display device with less display defects is realized. are doing.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a schematic configuration of a projection display device according to a first embodiment.
FIG. 2 is a diagram schematically showing an AA ′ cross section of FIG. 1;
FIG. 3 is a diagram schematically showing a modified example of a light shielding member.
FIG. 4 is a diagram illustrating a schematic configuration of a projection display device according to a second embodiment.
[Explanation of symbols]
2, 2R, 2G, 2B: light source, 22, 23, 24: liquid crystal light valve (light modulator), 26: projection lens (projection device), 30, 30c: projection type liquid crystal display device (projection type display device), 40 control board, 41 control circuit, 42 driver IC chip (semiconductor integrated circuit), 43 film member (flexible substrate), 46 convex part (light shielding part), 47 concave part (light shielding part)

Claims (7)

A light source, a light modulation device that modulates light emitted from the light source, and a projection display device including a projection device that projects light modulated by the light modulation device,
A control board on which a control circuit for controlling the light modulation device is mounted,
A flexible substrate connecting the control substrate and the light modulation device,
A semiconductor integrated circuit mounted on the flexible substrate to drive the light modulation device,
The control board is arranged such that one plate surface faces an optical path from the light source to the light modulation device,
The projection type display device, wherein the semiconductor integrated circuit is provided in a light shielding portion formed on a plate surface of the control substrate opposite to the optical path. 2. The light shielding unit according to claim 1, wherein the light shielding unit includes a concave portion formed on a plate surface opposite to the optical path, and the semiconductor integrated circuit is disposed inside the concave portion. Projection display device. The light-shielding portion is configured to include a convex wall portion formed on a plate surface opposite to the optical path, and the semiconductor integrated circuit is disposed inside the convex wall portion as viewed from the light source. The projection type display device according to claim 1, wherein: 4. The projection display device according to claim 1, wherein the semiconductor integrated circuit is disposed between the flexible substrate and the control substrate. 5. The control board is configured to include an insertion hole through which the flexible board can be inserted,
The flexible substrate has one end connected to the light modulator on the optical path side of the control substrate, and is inserted through the insertion hole of the control substrate on the side opposite to the optical path of the control substrate, The projection type display device according to claim 1, wherein the other end of the plate surface opposite to the optical path is connected to the control board. The projection display device according to claim 1, wherein the control circuit is configured to mount the control circuit on a plate surface opposite to the optical path. 7. The projection display device according to claim 1, wherein the semiconductor integrated circuit is configured by a semiconductor chip.

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