JP2005055662A - Projection display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection display device with excellent reliability by easily and completely preventing a malfunction of an integrated circuit chip due to photovoltaic effect and preventing a defect of the integrated circuit chip due to heat. <P>SOLUTION: The projection display device is equipped with a light source 2, an optical modulator 22 to modulate light from the light source 2 and a projector to project light modulated with the optical modulator 22 wherein the optical modulator 22 is equipped with a main body part 35 to carry out optical modulation, the integrated circuit chip 34 to control the main body part 35 and a frame body 41 to support the main body part 35. The frame body 41 is disposed so as to cover the integrated circuit chip 34. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a projection display device.

  In recent years, the demand for a high-resolution, low-power consumption and thin display device has increased, and research and development have been promoted. As one form of display device, there is known a projection display device (liquid crystal projector) that enlarges and projects an image emitted from an optical system using a light modulation device such as a liquid crystal light valve onto a screen through a projection lens. As the light modulation device, in addition to a liquid crystal light valve, a digital mirror device (hereinafter abbreviated as DMD) (registered trademark) has been put into practical use.

By the way, among the liquid crystal light valves used as the light modulation device of the projection display device as described above, a liquid crystal driving integrated circuit chip is mounted on the liquid crystal light valve to realize a higher definition image. There is also. However, when the active surface of the integrated circuit chip is irradiated with light, there is a possibility that the integrated circuit chip malfunctions due to the photovoltaic force, causing a malfunction in the display image. Therefore, a technique is disclosed in which light is not irradiated to an integrated circuit chip by providing a light shielding pattern that blocks light (for example, Patent Document 1).
JP 2001-154216 A (page 3, FIG. 1)

As described above, in the conventional projection display device, a light shielding pattern is provided so as not to irradiate light to the active surface of the integrated circuit chip, thereby preventing malfunction of the integrated circuit chip due to the photovoltaic force. However, since it is necessary to add a step of providing a light shielding pattern, there is a problem that it is difficult to perform easily.
At the same time, there has been a problem that light may strike the active surface of the integrated circuit chip due to a relative positional shift between the integrated circuit chip and the light shielding pattern when the integrated circuit chip is mounted, and malfunction may occur.

  Further, there is a problem that light from the light source of the projection display device hits the liquid crystal light valve, and the temperature of the integrated circuit chip increases together with the liquid crystal light valve. .

  The present invention has been made to solve the above-described problem, and it is possible to easily and completely prevent malfunction of an integrated circuit chip due to photovoltaic power, and to prevent malfunction of the integrated circuit chip due to heat. An object of the present invention is to provide a projection display device with excellent reliability.

  In order to achieve the above object, a projection display device of the present invention includes a light source, a light modulation device that modulates light of the light source, and a projection device that projects light modulated by the light modulation device. A projection display device, wherein the light modulation device includes a main body that performs the light modulation, an integrated circuit chip that controls the main body, and a frame that supports the main body. Is formed so as to block light applied to the integrated circuit chip.

That is, in the projection type display device of the present invention, since the frame body is formed so as to block the light applied to the integrated circuit chip, the frame body blocks the light from the light source and the light is applied to the integrated circuit chip. Can be prevented from being irradiated. Since the integrated circuit chip is not irradiated with the light, a malfunction of the integrated circuit chip due to photovoltaic force does not occur, and a projection display device with excellent reliability can be obtained. Further, since the integrated circuit chip is shielded simultaneously by simply supporting the main body portion with the frame, the malfunction of the integrated circuit chip can be easily prevented, and a highly reliable projection display device can be obtained.
Further, since the light is not directly irradiated onto the integrated circuit chip, the temperature rise of the integrated circuit chip can be suppressed, the malfunction of the integrated circuit chip due to heat can be prevented, and a highly reliable projection display device can be obtained. .

More specifically, in order to realize the above configuration, the frame body is composed of a pair of plate bodies that sandwich the main body portion, and the plate body positioned at least on the light source side among the pair of plate bodies is an integrated circuit chip. It is desirable to extend to a position where the light is shielded.
According to this configuration, the light irradiated to the integrated circuit chip can be more reliably shielded, so that the malfunction of the integrated circuit chip due to photovoltaic power and heat can be more reliably prevented, and the projection with excellent reliability. Type display device.

In order to realize the above configuration, more specifically, the frame body is preferably made of metal.
According to this configuration, since the frame is made of metal, the heat conductivity is good, and the heat generated by the light from the light source can be quickly radiated to the surroundings.
Examples of the metal used for the frame include metals having high thermal conductivity, such as magnesium.

To realize the above configuration, more specifically, the light modulation device may include a COF substrate in which an integrated circuit chip is mounted on a flexible substrate.
According to this configuration, since the integrated circuit chip is mounted on the flexible substrate, compared with the case where the integrated circuit chip is mounted on the main body of the light modulation device that is directly irradiated with light from the light source, An integrated circuit chip can be disposed in the region where the light irradiation intensity is weak. For this reason, the intensity of light applied to the integrated circuit chip becomes weak, and malfunction of the integrated circuit chip hardly occurs.
The COF substrate is obtained by mounting an integrated circuit chip on a flexible substrate using a COF (Chip on film / Chip on flexible print circuit) technology. Generally, wiring is provided between layers. An opening region is provided in one of the formed laminated substrates, and the integrated circuit chip is mounted on a wiring extending in the opening region.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic configuration diagram showing the projection type display device of the present embodiment, FIG. 2 is a side configuration diagram of the projection type display device, and FIG. 3 is a perspective configuration diagram of the liquid crystal light valve 22 shown in FIGS. is there. In all the drawings below, the film thicknesses and dimensional ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

  As shown in FIG. 1, the projection display device of this embodiment is a three-plate type equipped with transmissive liquid crystal light valves 22-24 for different colors of R (red), G (green), and B (blue). Projection type color display device, illumination device 1 having light source 2, fly-eye lens 3, 4 and polarization conversion device 4d, dichroic mirrors 13, 14, reflection mirrors 15-17, lenses 18-20, liquid crystal light valve 22 ˜24, a color separation / synthesis system 30 having a cross dichroic prism 25 and a projection optical system 40 having a projection lens 26.

  The light source 2 includes a lamp 7 such as a high-pressure mercury lamp or a metal halide 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 L in the liquid crystal light valves (light modulation devices) 22, 23, 24 that are the illuminated areas, the first fly-eye lens 3, Two fly-eye lenses 4 are sequentially installed. Each fly-eye lens 3, 4 is composed of a plurality of lenses 9, 10 (for example, 6 × 8 in this embodiment). The light L emitted from the light source 2 is made uniform in illuminance distribution by the fly-eye lenses 3 and 4 in the liquid crystal light valves 22 to 24 which are illuminated areas.

  The polarization conversion device 4d is composed of a polarization beam splitter array (PBS array) provided on the uniform illumination means side, and a half-wave plate array that converts the polarization direction of the polarized light reflected by the PBS array. The light polarization direction is aligned in one direction without impairing the light intensity.

  The dichroic mirrors 13 and 14 are formed, for example, by laminating a dielectric multilayer film on a glass surface, and selectively reflect predetermined color light and transmit light of other wavelengths. In other words, 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 green light reflecting dichroic mirror 14 transmits the blue light LB and reflects the green light LG among the blue light LB and the green light LG reflected by the dichroic mirror 13.

  As a result, among the light L incident from the illumination device 1, the red light LR passes through the dichroic mirror 13, is reflected by the reflection mirror 17, and enters the red light light valve 22. The green light LG is reflected by the dichroic mirror 14 and enters the green light valve 23. The blue light LB passes through the dichroic mirror 14 and then enters the blue light valve 24 through the relay system 21 including the relay lens 18, the reflection mirror 15, the relay lens 19, the reflection mirror 16, and the relay lens 20. It has become.

In the case of the present embodiment, the liquid crystal light valves 22 to 24 are configured as an active matrix type transmissive liquid crystal light valve, and are driven by a driving circuit described later based on the image signal subjected to signal processing. Yes. The color lights LR, LG, and LB modulated by the light valves 22 to 24 are incident on the cross dichroic prism 25.
The cross dichroic prism 25 has a structure in which right-angle prisms are bonded together, and a mirror surface that reflects the red light LR and a mirror surface that reflects the blue light LB are formed in a cross shape on the inner surface. Then, after the three color lights LR, LG, and LB are combined by these mirror surfaces to form light representing a color image, it is enlarged and projected onto the screen 27 by the projection lens (projection device) 26. Yes.

  Next, looking at the side configuration shown in FIG. 2, the color light LR color-separated from the light L emitted from the light source 2 enters the liquid crystal light valve 22 and is modulated, and the cross dichroic prism 25 and other color lights It is designed to be synthesized. In the present embodiment, as shown in FIG. 2, the liquid crystal light valve 22 includes a liquid crystal panel (main body part) 35, a COF substrate 32 connected to one substrate of the liquid crystal panel 35, the liquid crystal panel 35, and the COF substrate. A frame (frame body) 41 covering a part of 32 is provided. The COF substrate 32 includes a film substrate (flexible substrate) 33 and a driver IC (integrated circuit chip) 34 mounted on one surface thereof.

FIG. 3 is a perspective configuration diagram of the liquid crystal light valve 22 shown in FIG.
In the liquid crystal panel 35 according to the present embodiment, a liquid crystal layer is sandwiched between an element substrate 35a and a counter substrate 35b arranged to face each other, and the two substrates 35a and 35b are displayed in a region where they are planarly overlapped. A pixel portion 39 as a region is formed. The pixel unit 39 has a plurality of pixels arranged in a matrix in plan view. Two drive circuits 37 and 38 are mounted on the peripheral portion of the element substrate 35a, and one drive circuit 37 is electrically connected to a plurality of connection portions 36 formed in the vicinity thereof.

  The COF substrate 32 includes a film substrate 33 and a driver IC 34 mounted on one surface side (the back surface side in the drawing). The driver IC 34 and the driver IC 34 are mounted on the edge of the substrate surface on the side where the driver IC 34 is mounted. A terminal for connecting to the drive circuit 37 is provided, and is connected to a terminal on the element substrate 35 a side to form a connection portion 36. That is, the driver IC 34 and the drive circuit 37 are electrically connected via the connection unit 36. In the case of the present embodiment, the driver IC 34 and the terminal (connecting portion 36) of the COF substrate 33 are provided on the same surface side of the film substrate 33, so that a single-side mounting type COF substrate is used as the COF substrate 33. be able to.

  The frame 41 is composed of magnesium-made frame plates (plates) 41a and 41b arranged to face each other, and the liquid crystal panel 35 is sandwiched between the frame plates 41a and 41b. The frame plates 41 a and 41 b are formed to have a size that covers the element substrate 35 a and the counter substrate 35 b of the liquid crystal panel 35 and also covers the driver IC 34 mounted on the COF substrate 33. Further, the frame plates 41a and 41b are formed with openings 42 at positions corresponding to the pixel portions 39, which are display areas of the liquid crystal panel 35, and constitute drawer openings for drawing the COF substrate 33 to the outside of the frame 41. A concave portion 43 is formed. In addition, as a material for forming the frame 41, a metal having high thermal conductivity may be used in addition to the above-described magnesium.

In the projection display device of the present embodiment, as shown in FIG. 2, the driver IC 34 mounted on the COF substrate 32 is covered with a frame 41. With such a configuration, the active surface 34a is protected from the light of the light source 2 by the frame 41, and the malfunction of the driver IC 34 due to the photovoltaic force generated by irradiating the active surface 34a with light can be effectively prevented. ing.
Further, since the light from the light source 2 is not directly irradiated onto the driver IC 34 by the frame 41, the temperature rise of the driver IC 34 is suppressed, and the malfunction of the driver IC 34 due to this heat can be prevented. Further, the heat generated by the light source 2 and generated on the irradiation surface of the frame 41 is diffused by heat conduction and dissipated to the surroundings, so that the malfunction of the driver IC 34 can be prevented.

The active surface 34a of the driver IC 34 refers to a surface on which an element is formed on a semiconductor substrate. In the form of a packaged chip, the active surface is usually formed on the mounting surface side of the package. When an integrated circuit chip is mounted on a printed circuit board, the printed circuit board functions as a light-shielding member, so that troubles due to light irradiation are less likely to occur. Therefore, depending on the arrangement of the driver IC 34 and the light source 2, there is a possibility that an element malfunction of the integrated circuit chip occurs.
However, in the present invention, since the arrangement of the frame 41 is defined as described above, even if the driver IC 34 is mounted on the translucent film substrate 33, no malfunction occurs due to the light of the light source 2, and reliability is improved. It is an excellent projection display device.

  In the projection display device according to the present embodiment, the liquid crystal light valve 22 that is a light modulation device has a configuration in which a driver IC 34 is mounted on a flexible film substrate 33. With this configuration, the driver IC 34 can be disposed in a region where the light irradiation intensity is weak as compared with the case where the driver IC 34 is mounted on the element substrate 35a of the liquid crystal panel 35 to which the light of the light source 2 is directly irradiated. . For this reason, the intensity of the light applied to the driver IC 34 is weakened, the driver IC 34 is less likely to malfunction, and the projection display device is excellent in reliability.

  Further, with the above-described configuration, the area occupied by the circuit on the element substrate 35a can be reduced as compared with the case where all the drive circuits are mounted on the element substrate 35a of the liquid crystal panel 35. A reduction in size of 35 can be realized. In addition, among the drive circuits that are required to improve performance with the high definition of the liquid crystal panel 35, the driver IC 34 may be configured mainly by a circuit that requires high capability, and the capability of the element may be relatively low. If the circuit is configured to be mounted on the element substrate 35a, the high-performance driver IC 34 can be easily applied, and the manufacturability of the liquid crystal panel 35 can be improved. The performance liquid crystal light valve 22 can be manufactured at low cost.

  Further, when the drive circuits 37 and 38 are external drive circuits, it is necessary to draw out an extremely large number of terminals to the element substrate 35a in order to connect the drive circuit and the signal wiring of the pixel portion. In the refined liquid crystal panel, the pitch of the connection terminals is particularly narrow, and it is difficult to form the connection wiring between the external drive circuit and the liquid crystal panel. On the other hand, like the liquid crystal light valve 22 of the present embodiment, the driver IC 34 and the built-in drive circuit 37 cooperate to drive the pixel unit 39, thereby reducing the number of connection units 36. Therefore, the liquid crystal panel 35 can be easily reduced in size and definition.

FIG. 4 is a block diagram illustrating a configuration example of the liquid crystal light valve 22.
As a specific configuration of the driver IC 34 and the drive circuits 37 and 38 provided in the liquid crystal light valve 22 shown in FIG. 3, for example, a configuration in which functions shown in FIG. . FIG. 4 is a block diagram illustrating a configuration example of the liquid crystal light valve according to the present embodiment. As illustrated in FIG. 4, the pixel unit 39 includes a plurality of pixels arranged in a matrix on the liquid crystal panel 35. In addition, a multiplexer (drive circuit) 37 and a Y driver (drive circuit) 38 are provided in the liquid crystal panel 35. The pixel unit 39 includes an active matrix type pixel having a TFT element as a switching element, specifically, a data line and a scanning line arranged in stripes in directions intersecting with each other, and the vicinity of the intersection. And a pixel electrode for driving the liquid crystal. The data lines are connected to the multiplexer 37, and the scanning lines are connected to the Y driver 38.
In addition, a driver IC 34 that is an external drive circuit is connected to the liquid crystal panel 35 via a signal line group 52, and a timing control circuit 51 that controls them is connected to the liquid crystal panel 35 and the driver IC 34. The pixel unit 39 is driven and controlled by a Y driver 38, a multiplexer 37, a driver IC 34, and a timing control circuit 51 which are driving circuits provided in the periphery thereof.

The image data DATA, the latch timing signal LP, the shift register start signal ST, the data clock signal CLX, and the selection signals S1, S2, and S3 shown in FIG. 4 are supplied from the timing control circuit 51 to the driver IC 34. . The timing control circuit 51 supplies a Y driver start signal DY and a line shift signal CLY to the liquid crystal panel 35. The driver IC 34 includes a selector that selects and outputs one image signal from the image data DATA input from the timing control circuit 51. The selector includes a shift register, a latch circuit, and a driver circuit. Are connected in a permutation.
The driver IC 34 inputs the image data DATA received from the timing control circuit 51 to the latch circuit, and from the plurality of image data DATA stored in the latch circuit based on the select signals S1, S2, S3 supplied simultaneously. One image data corresponding to the select signal is selected and output to the multiplexer 37 via the signal line group 52. On the other hand, the multiplexer 37 outputs the image data DATA received from the driver IC 34 to the data line of the pixel column corresponding to the select signals S1, S2, S3. The pixels in each row are switched by the gate signal output from the Y driver 38 to the scanning line in synchronization with the output to the data line, so that an image is displayed.

  According to the above configuration, a plurality of pieces of image data DATA input to the selector of the driver IC 34 are made to correspond to any of the three types of select signals, and only the image data DATA corresponding to the select signals is switched while switching these select signals. Since the signal is output to the multiplexer 37, the number of the signal line groups 52 connected to the liquid crystal panel and the drive circuit is reduced to 1/3 as compared with the case where the image data DATA is output to all the signal lines of the pixel column. Since the number of connection portions 36 shown in FIG. 3 can be reduced, the connection between the COF substrate 33 and the liquid crystal panel 35 can be facilitated. Since only the multiplexer 37 mainly composed of a switch circuit having a relatively simple structure is mounted on the liquid crystal panel 35, the area occupied by the drive circuit in the liquid crystal panel 35 can be reduced. This is extremely advantageous for downsizing. Furthermore, since the driver IC 34 is externally attached, a driver IC having higher capability can be easily applied, and high definition of the pixel portion 39 can be easily coped with.

FIG. 5A and FIG. 5B are configuration diagrams of other forms of the projection display device according to the present invention.
In the above embodiment, as shown in FIGS. 2 and 3, the terminal on the COF substrate 32 side constituting the terminal portion 36 is formed on the surface on which the driver IC 34 is mounted. Depending on the specifications of FIG. 22, as shown in FIG. 5A, the surface on which the integrated circuit chip 34 is mounted and the surface on which the terminals constituting the connection portion 36 are formed (see FIG. 4) are opposite to each other. A COF substrate 32 'may be used. With such a configuration, the active surface 34a of the integrated circuit chip 34 is disposed in the direction opposite to the light source 2 side, and is effectively shielded by the integrated circuit chip 34 itself.
Alternatively, as shown in FIGS. 2 and 3, the terminal on the COF substrate 32 side constituting the terminal portion 36 is formed on the surface on which the driver IC 34 is mounted, and is shown in FIG. Thus, the element substrate 35a may be disposed on the light source 2 side. Even in such a configuration, the active surface 34a of the integrated circuit chip 34 is disposed opposite to the light source 2 side, and is effectively shielded by the integrated circuit chip 34 itself.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the driver IC 34 is described as being adapted to be mounted on the COF substrate 32. However, the driver IC 34 is not limited to being mounted on the COF substrate 32, and the driver IC 34 is mounted on the element substrate. The present invention can be applied to various other mounting formats such as COG (Chip on Glass) mounting mounted on 35a.

FIG. 1 is a configuration diagram of a projection display device according to an embodiment of the present invention. FIG. 2 is a side view of the configuration. FIG. 3 is a perspective configuration diagram of the liquid crystal light valve shown in FIG. FIG. 4 is a block diagram showing a configuration example of the liquid crystal light valve. FIG. 5 is a configuration diagram of another embodiment of the projection display device of the present invention.

Explanation of symbols

  2 ... Light source 22, 23, 24 ... Liquid crystal light valve (light modulation device), 26 ... Projection lens (projection device), 33 ... Film substrate (flexible substrate), 34 ... Driver IC (integrated circuit chip), 35 ... Liquid crystal panel (main body), 41 ... Frame (frame body), 41a, 41b ... Frame plate (plate body)

Claims (4)

A projection display device comprising: a light source; a light modulation device that modulates light from the light source; and a projection device that projects light modulated by the light modulation device,
The light modulation device includes a main body that performs the light modulation, an integrated circuit chip that controls the main body, and a frame that supports the main body.
The projection display device, wherein the frame is formed so as to shield light applied to the integrated circuit chip. The frame is composed of a pair of plates that sandwich the main body,
2. The projection display device according to claim 1, wherein, of the pair of plates, at least a plate located on the light source side extends to a position where the integrated circuit chip is shielded from light. The projection display device according to claim 1, wherein the frame is made of metal. 4. The projection display device according to claim 1, wherein the light modulation device includes a COF substrate in which the integrated circuit chip is mounted on a flexible substrate.

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