JP2000193947A - Liquid crystal display device, projection type liquid crystal display device and method for connecting liquid crystal display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the thickness and cost of a liquid crystal display device by executing the connection of a driving circuit and a liquid crystal display panel without using a flexible substrate. SOLUTION: Four leg parts of a hook 15 are fitted and mounted into the grooves of a liquid crystal display panel socket 11. The liquid crystal display panel socket 11 is previously mounted by means of lock screws 16 to a circuit board 12 and, therefore, the liquid cristal display panel socket 11 the circuit board 12, the liquid crystal display panel 13, a heat radiation plate 14 in common use as a pressing plate and the hook 15 are integrated by mounting of the hook 15. Heat radiation silicone is disposed between the liquid crystal display panel 13 and the heat radiation plate 14 in common use as the pressing plate in order to enhance heat radiatability. The upper part (the side arranged with the liquid crystal display panel 13) of the heat radiation plate 14 in common use as the pressing plate is formed to a recessed shape so as not to affect the cell gap of the liquid crystal display panel 13. The heat radiation silicone is placed in the recessed part of the recessed shape part.

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, a projection type liquid crystal display device, and a method of connecting a liquid crystal display panel, and more particularly to a liquid crystal display panel and a circuit board having a driving circuit for driving the liquid crystal display panel. , A projection type liquid crystal display device, and a method for connecting a liquid crystal display panel.

[0002]

2. Description of the Related Art A liquid crystal display panel is used for a display section of a personal computer, a finder of a video camera, a projection display device, and the like.

The connection between a liquid crystal display panel and its driving circuit is described in, for example, JAE No. 18 1995-3, FIG.
Are disclosed.

As shown in FIG. 10, a liquid crystal display panel 102 is attached to a holder 103 by a hook 100 with a liquid crystal display panel cover 101 interposed therebetween. And
By attaching the flexible substrate 104 to the holder 103, electrical connection between the liquid crystal display panel and an external drive circuit is made via the flexible substrate 104.

[0005]

By the way, with the demands for thinning and cost reduction of each of the above devices, there is also a demand for thinning and cost reduction of the liquid crystal display device.

The present invention relates to a liquid crystal display device in which a liquid crystal display panel is directly mounted on a circuit board on which a drive circuit is mounted, and the drive circuit and the liquid crystal display panel can be connected without using a flexible substrate. It is an object to provide a display device and a method for connecting a liquid crystal display panel.

[0007]

A liquid crystal display device according to the present invention comprises a liquid crystal display panel, a circuit board provided with a drive circuit for driving the liquid crystal display panel, a liquid crystal display panel which holds the liquid crystal display panel, and is mounted on the circuit board. A holder for fixing, wherein an electrode provided on the liquid crystal display panel and a connector provided on the holder are electrically connected, and the connector is electrically connected to the circuit board. It is assumed that.

The liquid crystal display device according to the present invention is a method for connecting a liquid crystal display panel to a circuit board provided with a drive circuit for driving the liquid crystal display panel, the liquid crystal display panel being connected to the circuit board using a holder. Then, by fixing the liquid crystal display panel to the circuit board using the holder, an electrical connection between an electrode provided on the liquid crystal display panel and a connector provided on the holder is performed, and via the connector Electrical connection between the circuit board and the liquid crystal display panel.

Further, a projection type liquid crystal display device of the present invention comprises a liquid crystal display device of the present invention, a light source for irradiating the liquid crystal display device with light, and an optical system for projecting transmitted light or reflected light from the liquid crystal display device. And

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an exploded perspective view showing a liquid crystal display panel mounting portion according to the liquid crystal display device of the present invention. In FIG. 1, reference numeral 11 denotes a liquid crystal display panel (LCD) socket serving as a holder, 12 denotes a circuit board on which peripheral circuits for driving a liquid crystal display (LCD) panel 3 are mounted, and 13 denotes a liquid crystal display (LC).
D) Panels 14 press liquid crystal display panel 13 against liquid crystal display panel socket 11 and
A press plate and a heat radiator for radiating heat from the circuit board 15; a circuit board 12, a liquid crystal display panel 13, a press plate and a heat radiator 14;
A hook 16 is attached to the liquid crystal display panel socket 11 through the socket, and 16 is a fixing screw for attaching the liquid crystal display panel socket 11 to the circuit board 12.

The four legs of the hook 15 are fitted into the grooves of the liquid crystal display panel socket 11, and the hook 15 is attached to the liquid crystal display panel socket 11. The liquid crystal display panel socket 11 is fixed to the circuit board 12 with a fixing screw 16 in advance.
The liquid crystal display panel socket 11, the circuit board 12, the liquid crystal display panel 13, the pressing plate and heat sink, and the hook 15 are integrated by mounting the hook 15.

FIG. 2 is a perspective view showing a state where the liquid crystal display panel socket is mounted on the circuit board. As shown in FIG. 2, the liquid crystal display panel socket 11 is attached to the circuit board 12 with fixing screws 16. In addition, 4 of hook 15
The state where the legs of the book are fitted into the grooves of the liquid crystal display panel socket 11 and attached are shown.

FIG. 3 is a perspective view showing a state in which a pressing plate and a heat sink are attached by hooks. As shown in FIG. 3, the pressing plate and heat sink 14 is attached by the hook 15. The pressing plate and heat sink 14 is provided with a groove in order to enhance heat dissipation efficiency.

FIG. 4 is a sectional view of a liquid crystal display panel mounting portion for showing a mounting state. Electrical connection between the liquid crystal display panel 13 and the circuit board 12 is performed by connecting a contact terminal (connector) 17 provided in the liquid crystal display panel socket 11 serving as a holder and an electrode of the liquid crystal display panel 13. . The electrodes of the liquid crystal display panel 13 are taken out on two sides of the panel, and are connected to the contact terminals 17 provided according to the number of electrodes on the two sides of the liquid crystal display panel. The contact terminals 17 and the circuit board 12 are not only brought into contact with each other, but also connected with solder so that electrical connection is reliably performed. Liquid crystal display panel 1
The connection between the electrode 3 and the contact terminal 17 is made by the hook 15
The pressing plate / radiator plate 14 is pressed by this, and the liquid crystal display panel 13 is further pressed via the pressing plate / radiator plate 14 to make contact with the contact terminals 17 previously connected to the circuit board 12. . The connection with the solder may be performed after the hook 15 is attached.

Contact terminals 17 and liquid crystal display panel 13
It is desirable that the electrode is contacted with 50 g or more per pin. In addition, the electrodes of the liquid crystal display panel are provided with a corrosion prevention coat in advance and are broken at the time of contact with the connector terminal, thereby preventing the corrosion of the electrodes.

The reason why the weight per pin is 50 g or more is that the electrode material of the panel to be connected (for example, aluminum)
In some cases, non-conductive oxide layers are formed on the surface due to oxygen in the air, and simply touching the electrodes may not provide sufficient conduction, and may require some force to penetrate the oxide layers. Because there is. Further, as a coating material for corrosion prevention, TSE399 (made by Toshiba Silicone, non-corrosive, moisture-curable type) can be mentioned as a silicone resin.

Between the liquid crystal display panel 13 and the pressing plate and heat radiating plate 14, a heat radiating silicone 18 is provided to enhance heat radiating properties.
Is provided. The upper portion of the pressing plate / radiator plate 14 (on the side where the liquid crystal panel is disposed) has a concave shape so as not to affect the cell gap of the liquid crystal display panel, and the heat radiation silicone 18 is placed in the concave portion of the concave portion. I have.

The use of the liquid crystal display device of the present invention is not particularly limited. However, since the liquid crystal display surface may be small with respect to the projection surface, there is an advantage that the circuit board can be made relatively large. In particular, it can be suitably used for a projection type liquid crystal display device.

FIG. 5 is a schematic view of a main part of an optical system of an embodiment of a dosing type liquid crystal display device using the liquid crystal display device of the present invention. 5A shows a top view, FIG. 5B shows a front view, and FIG. 5C shows a side view.

In this embodiment, a microlens is used as a liquid crystal display panel, and one panel has three colors of R, G, and B.
A reflective liquid crystal display panel capable of modulating color was used. However, the present invention can also be suitably used for the purpose of modulating the three colors of R, G, and B when a color filter is attached to a liquid crystal display panel. Although the optical arrangement is different, the present invention can also be used when a transmission type liquid crystal display panel is used.

Further, it is possible to constitute a display device using two or three transmission / reflection type liquid crystal display panels without using microlenses and color filters.

In FIG. 5, reference numeral 1 denotes a projection lens, which projects image information displayed on a display panel (liquid crystal display panel) 2 using liquid crystal with a micro lens onto a predetermined surface. Reference numeral 3 denotes a polarization beam splitter (PBS) that transmits, for example, S-polarized light and reflects P-polarized light. 40 is R
(Red light) Reflective dichroic mirror, 41 is B / G
(Blue & green light) Reflective dichroic mirror, 42 is B
(Blue light) reflective dichroic mirror, 43 is a high-reflection mirror that reflects all color light, 50 is a Fresnel lens, 51 is a convex lens (positive lens), 6 is a rod-type integrator, 7 is an elliptical reflector, and a metal halide or A light emitting surface 8a of an arc lamp (light source) 8, such as UHP, is provided.

The R (red light) reflecting dichroic mirror 40, the B / G (blue & green light) reflecting dichroic mirror 41, and the B (blue light) reflecting dichroic mirror 42 are shown in FIGS. 6 (a) and 6 (b), respectively. , (C). These dichroic mirrors are arranged three-dimensionally together with the high-reflection mirror 43 as shown in the perspective view of FIG. 7, and emit white illumination light from the light source 8 into three R, G, and B light sources as described later. Each of the primary color lights illuminates the liquid crystal display panel 2 from three-dimensionally different directions with respect to the liquid crystal display panel 2 while being separated into color lights.

Here, a description will be given in accordance with the progress of the light beam from the light source 8. First, the white light beam emitted from the lamp 8 is condensed by the elliptical reflector 7 at the entrance (incident surface) 6 a of the integrator 6 in front of it. As the light travels while being repeatedly reflected in the integrator 6, the spatial intensity distribution of the light beam becomes uniform. The luminous flux emitted from the exit 6b of the integrator 6 is a convex lens 51.
And the Fresnel lens 50 in the x-axis direction (FIG. 5B).
The light beam is converted into a parallel light beam (reference) and reaches the B reflection dichroic mirror 42 first.

The B reflection dichroic mirror 42 reflects only the B light (blue light), and the R reflection dichroic mirror 40 at a predetermined angle with respect to the z axis in the z-axis direction, that is, on the lower side (reference to FIG. 5B). Head for. On the other hand, color light (R / G light) other than the B light is reflected by the B reflection dichroic mirror 4.
2, the light is reflected by the high-reflection mirror 43 at right angles in the z-axis direction (downward), and also travels toward the R reflection dichroic mirror 40.

Here, both the B reflection dichroic mirror 42 and the high reflection mirror 43 are based on FIG.
The luminous flux (x-axis direction) from integrator 6 is converted to z-axis
The high-reflection mirror 43 is arranged so as to be just 4 ° with respect to the xy plane with the y-axis direction as the rotation axis.
The inclination is 5 °. On the other hand, the B reflection dichroic mirror 42 is also set at an angle smaller than 45 ° with respect to the xy plane with the rotation axis in the y-axis direction.

Therefore, R reflected by the high reflection mirror 43
The / G light is reflected in the negative z-axis direction, whereas the B light reflected by the B reflecting dichroic mirror 42 is directed downward at a predetermined angle (tilt in the xz plane) with respect to the z axis. Here, in order to make the illumination ranges of the B light and the R / G light on the liquid crystal display panel 2 coincide, the principal ray of each color light is
The amount of shift and the amount of tilt of the high reflection mirror 43 and the B reflection dichroic mirror 42 are selected so as to intersect with each other.

Next, as described above, the downward direction (z-axis direction)
The R / G / B light traveling toward R / G is directed to an R reflection dichroic mirror 40 and a B / G reflection dichroic mirror 41, which are located below a B reflection dichroic mirror 42 and a high reflection mirror 43. The G reflection dichroic mirror 41 has a 45
The R-reflection dichroic mirror 40 is also set at an angle smaller than 45 ° with respect to the xz plane with the x-axis direction as the rotation axis.

Therefore, of the R / G / B light incident on these, first, the B / G light passes through the R reflection dichroic mirror 40 and is reflected at right angles by the B / G reflection dichroic mirror 41 in the y-axis + direction. , The liquid crystal display panel 2 after being polarized through the PBS 3 and horizontally arranged on the xz plane
To illuminate.

Among them, the B light is as described above (FIG. 5).
(A), FIG. 5 (b)) Since the light travels at a predetermined angle (tilt in the xz plane) with respect to the x-axis, after reflection by the B / G reflection dichroic mirror 41, it is predetermined with respect to the y-axis. (Tilt in the xy plane) is maintained, and the liquid crystal display panel 2 is illuminated with the angle as the incident angle (the xy plane direction). B / G reflection dichroic mirror 4 for G light
1, the light is reflected at a right angle, travels in the positive y-axis direction, is polarized through the PBS 3, and then illuminates the liquid crystal display panel 2 at an incident angle of 0 °, that is, vertically.

As for the R light, B / G
The R reflection dichroic mirror 40 disposed in front of the reflection dichroic mirror 41 reflects the light in the y-axis + direction on the R reflection dichroic mirror 40.
(C) As shown in (side view), the liquid crystal display panel 2 advances in the y-axis + direction at a predetermined angle (tilt in the yz plane) with respect to the y-axis, and is polarized through the PBS 3. Illumination is performed at an angle with respect to the axis as an incident angle (yz plane direction).

As described above, in order to make the illumination ranges of the R, G, and B color lights on the liquid crystal display panel 2 coincide with each other, the B / B of each color light crosses the liquid crystal display panel 2 so as to intersect.
The shift amount and the tilt amount of the G reflection dichroic mirror 41 and the R reflection dichroic mirror 40 are selected.

Further, as shown in FIG. 6, the cut wavelength of the B / G reflection dichroic mirror 41 is 570 nm,
The cut wavelength of the reflection dichroic mirror 40 is 600 n
m, unnecessary orange light passes through the B / G reflection dichroic mirror 41 and is discarded outside the optical path. Thereby, an optimal color balance is obtained.

As will be described later, each of the R, G, and B lights is reflected and polarized by the liquid crystal display panel 2, returns to the PBS 3, and is reflected on the PBS surface 3a of the PBS 3 in the positive x-axis direction.
This light beam enters the projection lens 1. The projection lens 1 enlarges and projects an image displayed on the liquid crystal display panel 2 onto a screen (not shown).

Each of R, G,
Since the B light has a different incident angle, the R, G, and B lights reflected therefrom also have different emission angles. However, the projection lens 1 has a lens diameter large enough to capture all of them. And an opening. However, the inclination of the light beam incident on the projection lens 1 is parallelized by each color light passing twice through the micro lens, and the inclination of the incident light on the liquid crystal display panel 2 is maintained.

FIG. 8 is a block diagram of a liquid crystal display panel and a driving circuit for driving the panel. The example in FIG. 8 is an example in which blocks required at least in an electric circuit from an external image signal input to a liquid crystal display panel are integrated on one substrate.

In FIG. 8, a liquid crystal display panel 22 and an ASIC 23 for performing signal correction, image processing, gamma correction processing, and the like on a digital image signal, and sending the processed signal to the liquid crystal display panel 22 on one substrate 21. , R, G, and B analog image signals are converted into digital image signals, and AS
A / D converters 24a, 24b, 24c to be sent to the IC 23,
A preamplifier 25 for analogly amplifying an image input signal from the outside, a synchronization pulse of the external signal is detected, the synchronization pulse is locked, and the ASIC 23 and the AD converters 24a to 24c are locked.
(Phase Locked Loop) to supply synchronization pulse to
An SGRAM (Synchronous Graphic Random) that temporarily stores a signal being processed before and after processing by the circuit 26 and the ASIC 23.
Access Memory) 27a, 27b, 27c, SGRA
M, ASIC, TG (Timing Generator) 28 for supplying a timing pulse of the liquid crystal display panel, and the like are mounted. Although three SGRAMs are used, this number varies depending on the type of processing required. In addition, an SDRAM, a DRAM, or the like can be used according to characteristics required as appropriate.

The number shown in the signal path in the figure is 8 bi.
Using an AD (twist pair twice as many lines) converter of t, X
This is an example of the number of lines in the case of a digital panel having the number of pixels of GA (1024 × 768), and this number changes depending on the panel specifications and the number of AD conversion bits.

FIG. 9 shows a configuration example of a liquid crystal display panel.
In the present embodiment, a so-called “digital panel” having a D / A converter for converting a digital input signal into an analog signal is provided on-chip a shift register around the display area.
An example was shown.

In FIG. 9, the display area 31 is composed of a large number of pixel switches in a matrix. The horizontal shift registers 32a and 32b output timings for writing digital image signals from above and below, respectively, in the display area. In order to prevent burn-in of the liquid crystal, for example, the shift register 32a operates during an odd field, the shift register 32b pauses, and vice versa during an even field.
In the odd field, the positive signal line 33a supplies a digital signal to the latch. The latch 34a receives the timing from the shift register 32a and converts the stored digital signal into a positive-polarity DAC (Digital-Analog converter).
rter) to the group 35. The positive polarity DAC 35 writes the offset-corrected signal in the display area. The offset correction ADC (Analog-Digital converter) 37a corrects the offset of the DAC measured in advance with reference to the reference voltage, and corrects the signal of the positive polarity DAC to a signal having no offset. The reference voltage circuit 38a supplies a reference voltage serving as a reference for determining the offset amount to the offset correction ADC 37a.

In the even field, the function of the image signal line 33a in the odd field is controlled by the image signal line 33b, the function of the latch 34a is controlled by the latch 34b, and the positive polarity DAC 35 is controlled.
The function of the negative polarity DAC 36 is performed by the offset correction ADC 3.
The function of 7a is corrected by the offset correction 37b.
The reference voltage circuit 38b performs the same operation as the reference voltage circuit 38b.

FIG. 11 is a schematic diagram of a layout diagram of a circuit chip of the liquid crystal display panel of FIG. As in FIG. 9, a shift register is formed around the display area, and a D / A converter for converting a digital signal into an analog signal is also provided.

On the short side of the panel, signal input electrodes are provided. In consideration of the displacement when mounted on a socket, the size of the panel is 0.3 × 0.5 mm and the distance is 0.5 mm. installed. Electrodes of 52 pins were arranged on one side and 104 pins were arranged on both sides.

[0045]

As described above, according to the present invention,
The liquid crystal display panel is directly mounted and integrated on the circuit board on which the drive circuit is mounted, and the connection between the drive circuit and the liquid crystal display panel can be performed without using a flexible substrate. As a result, the thickness of the liquid crystal display device can be reduced. Cost reduction can be achieved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a liquid crystal display panel mounting portion according to a liquid crystal display device of the present invention.

FIG. 2 is a perspective view showing a state where a liquid crystal display panel socket is attached to a circuit board.

FIG. 3 is a perspective view showing a state in which a pressing plate and a heat sink are attached by hooks.

FIG. 4 is a cross-sectional view of a liquid crystal display panel mounting portion for showing a mounting state.

FIG. 5 is a schematic view of a main part of an optical system of an embodiment of a dosing type liquid crystal display device using the liquid crystal display device of the present invention.

FIG. 6 is a diagram illustrating a spectral reflection characteristic of a reflection dichroic mirror.

FIG. 7 is a perspective view showing an arrangement example of a dichroic mirror.

FIG. 8 is a block diagram of a liquid crystal display panel and a driving circuit for driving the panel.

FIG. 9 is a diagram showing a configuration example of a liquid crystal display panel according to the present invention.

FIG. 10 is an exploded perspective view showing a conventional example of a connection structure between a liquid crystal display panel and a driving circuit thereof.

11 is a schematic diagram of a layout diagram of a circuit chip of the liquid crystal display panel of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Liquid crystal display panel (LCD) socket 12 Circuit board 13 Liquid crystal display (LCD) panel 14 Pressing plate and heat sink 15 Hook 16 Fixing screw 17 Contact terminal (connector) 18 Heat dissipation silicone

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H089 HA40 KA17 QA11 QA16 TA12 TA16 TA17 TA18 2H092 GA44 GA52 GA56 NA25 PA08 PA13 RA05 5C094 AA15 AA35 AA44 BA16 BA43 CA19 CA24 DB02 DB05 EA10 FA01 FA02 GB01 5G435 AA12 AA12 CC DD04 EE02 EE06 EE07 EE08 EE13 EE21 EE32 EE34 EE44 EE50 GG02 GG04 GG05 GG06 GG24 KK02

Claims (12)

[Claims] 1. A liquid crystal display panel, comprising: a liquid crystal display panel; a circuit board including a driving circuit for driving the liquid crystal display panel; and a holder for holding the liquid crystal display panel and fixing the liquid crystal display panel to the circuit board. And a connector provided on the holder is electrically connected, and the connector is electrically connected to the circuit board. 2. The liquid crystal display device according to claim 1, wherein the holder is attached to the circuit board, and the liquid crystal display panel is held by the holder by being pressed by the holder. . 3. The liquid crystal display device according to claim 1, wherein the electrodes of the liquid crystal display panel are extended to two sides of the liquid crystal display panel. 4. The liquid crystal display device according to claim 1, wherein the pressing of the liquid crystal display panel is performed by a heat radiating plate that radiates heat from the liquid crystal display panel. . 5. The liquid crystal display device according to claim 4, wherein the heat radiating plate has a concave shape on the surface where the liquid crystal display panel is disposed. 6. A method for connecting a liquid crystal display panel to a circuit board having a driving circuit for driving the liquid crystal display panel, wherein the liquid crystal display panel is connected to the circuit board using a holder. By fixing the liquid crystal display panel to the circuit board, the electrodes provided on the liquid crystal display panel are electrically connected to the connector provided on the holder, and the circuit board and the liquid crystal are connected via the connector. A method for connecting a liquid crystal display panel, comprising making an electrical connection with a display panel. 7. The method according to claim 6, wherein the holder is attached to the circuit board and the connector is connected to the circuit board before mounting the liquid crystal display panel. . 8. The connection method for a liquid crystal display panel according to claim 6, wherein the liquid crystal display panel is held by the holder by being pressed by the holder. 9. The connection of the liquid crystal display panel according to claim 6, wherein the electrodes of the liquid crystal display panel are extended to two sides of the liquid crystal display panel. Method. 10. The liquid crystal display panel according to claim 6, wherein the pressing of the liquid crystal display panel is performed by a heat radiating plate that radiates heat from the liquid crystal display panel. Connection method. 11. The method for connecting a liquid crystal display panel according to claim 10, wherein a surface of the heat sink near the liquid crystal display panel has a concave shape. 12. The liquid crystal display device according to claim 1, a light source for irradiating the liquid crystal display device with light, and projecting transmitted light or reflected light from the liquid crystal display device. A projection type liquid crystal display device having an optical system.