JP5196694B2 - Image display device and electronic apparatus equipped with the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image display device, and more particularly to an image display device capable of displaying two screens and an electronic apparatus including the same.
[0002]
[Prior art]
In recent years, liquid crystal display devices have been used in various fields by taking advantage of thinness, light weight, and low power consumption. For example, a light-transmissive liquid crystal display device includes a liquid crystal display panel in which a liquid crystal layer is held between a pair of electrode substrates, a light source unit that illuminates the liquid crystal display panel, a drive circuit substrate that drives the liquid crystal display panel, It has.
[0003]
Further, as a kind of image display device, a device having two liquid crystal display devices and capable of displaying two screens has been proposed. According to this type of image display device, two sets of the above-described liquid crystal display panel, light source unit, and drive circuit board are provided, and for example, two liquid crystal display devices are arranged back to back. Therefore, this image display device can display images on both the front and back sides, and can expand the range of use.
[0004]
[Problems to be solved by the invention]
However, a display device capable of two-screen display as described above is provided with two sets of liquid crystal panels, light source units, and drive circuit boards, and requires two image signal inputs, and thus has a large number of parts. As the cost reduction increases, it becomes difficult to reduce the thickness and weight of the entire apparatus.
[0005]
The present invention has been made in view of the above points, and an object of the present invention is to provide an image display device capable of displaying a plurality of screens and capable of reducing the manufacturing cost, reducing the thickness, and reducing the weight, and an electronic apparatus including the image display device. There is to do.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an image display device according to the present invention includes a display area in which display pixels are arranged in a matrix , a drive circuit for signal lines and scanning lines , and a relay wiring extending along a side edge. A first liquid crystal display panel having a formed array substrate; a display region in which display pixels are arranged in a matrix; and a second substrate having an array substrate on which drive circuits for signal lines and scanning lines are formed. a liquid crystal display panel, the first and a control circuit board for controlling the second liquid crystal display panel, the driving circuit of the first liquid crystal display panel and the first connection cable for connecting the one end and the control circuit board of the relay wiring When, the relay and the second connection cable for connecting the drive circuit of the wiring other end and the second liquid crystal display panel, the second connecting said via a cable first liquid crystal display panel and the second liquid crystal The display panel is opposed, it is characterized by comprising a light source unit which is interposed between the counter are both liquid crystal display panel that has.
[0007]
The electronic device according to the present invention rotates between a device main body provided with a data input unit, and a closed position that covers the data input unit and an open position that opens the input unit with respect to the device main body. A housing provided in a possible manner, the housing including a first opening formed on a surface corresponding to the data input unit and a second opening formed on the opposite surface; and disposed in the housing. The display area of the first liquid crystal display panel is opposed to the first opening, and the display area of the second liquid crystal display panel disposed in the housing is opposed to the second opening. And an image display device as described above .
[0008]
According to the image display device and the electronic apparatus, the second display panel is connected to the control circuit board via the relay wiring formed on the array substrate of the first display panel, and is output from the single control circuit board. Both the first and second display panels are driven by the image control signal. A long flexible printed circuit board for connecting the control circuit board and the second display panel can be omitted. Therefore, the number of parts can be reduced, and the image display device and the electronic device can be reduced in thickness and weight, and the manufacturing cost can be reduced.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which an image display device according to the present invention is combined with a laptop personal computer will be described in detail with reference to the drawings.
As shown in FIG. 1, a personal computer as an electronic device includes a flat rectangular device main body 10 and a display unit 12 supported by the device main body so as to be freely opened and closed.
[0010]
The apparatus main body 10 includes a rectangular base portion 16 having an open top surface and a cover portion 14 joined to the base portion so as to cover the opening of the base portion. A keyboard 18 and a click switch 19 that function as a data input unit are provided on the upper surface of the device main body 10, and a plurality of convex portions 23 are provided on the rear end portion of the upper surface of the device main body 10.
[0011]
The display unit 12 includes a flat rectangular box-shaped display housing 22 corresponding to the shape of the device main body 10 and a liquid crystal display panel (described later) housed in the display housing. The display unit 12 has a pair of leg portions 26 protruding from the rear end portion of the display housing 22, and these leg portions 26 are supported by the convex portion 23 of the device main body 10 via a hinge (not shown) and are rotatably supported. Part.
[0012]
As a result, the display unit 12 can freely rotate between the open position shown in the figure where the keyboard 18 can be opened and operated, and the closed position shown in FIG. It has become.
[0013]
Next, the display unit 12 that functions as an image display device will be described in detail.
As shown in FIGS. 1 to 3, the display unit 12 includes a first liquid crystal display panel 30, a second liquid crystal display panel 50, a light source unit 70, a control circuit board 52 that controls the first and second liquid crystal display panels, and A display housing 22 in which these are stored is provided. The first and second liquid crystal display panels 30 and 50 are provided back to back with the light source unit 70 interposed therebetween, and in a state where the display unit 12 is rotated to the open position, the first liquid crystal display panel is the front side of the display unit 12, The second liquid crystal display panel is provided so as to be positioned on the back side of the display unit 12.
[0014]
As shown in FIGS. 3 and 4, the first liquid crystal display panel 30 has a rectangular effective display area 32 and is configured as a light transmission type capable of color display. More specifically, the first liquid crystal display panel 30 is held by a rectangular array substrate 33 and a counter substrate 34 which are arranged to face each other with a predetermined cell gap therebetween, and an alignment film is interposed between these substrates. And a liquid crystal layer 35. The array substrate 33 and the counter substrate 34 are bonded to each other by a sealing material 36. Further, rectangular polarizing plates 37 and 38 are attached to the outer surfaces of the array substrate 33 and the counter substrate 34, respectively, and are arranged so that their polarization axes are orthogonal to each other.
[0015]
The array substrate 33 has a glass substrate. On this glass substrate, for example, 1024 × 3 signal lines 40 and 768 scanning lines 41 are arranged in a matrix so as to be substantially orthogonal. Near the intersection of each signal line 40 and each scanning line 41, a thin film transistor (hereinafter abbreviated as TFT) 42 using a polycrystalline silicon film in the channel region is disposed. In each TFT 42, the gate electrode is connected to the scanning line 41, the drain region is connected to the signal line 40, and the source region is connected to the pixel electrode 43 made of ITO (indium tin oxide).
[0016]
Further, on the glass substrate of the array substrate 33, a signal line driving circuit 44 connected to the signal line 40 and a scanning line driving circuit 45 connected to the scanning line 41 are provided. A relay wiring 47 is formed on the array substrate 33 and extends along the substantially entire side edge of the array substrate outside the scanning line driving circuit 45. These drive circuits 44 and 45 and relay wiring 47 are formed on the glass substrate in the same process as the TFT 42.
[0017]
The signal line drive circuit 44 is composed of, for example, a shift register (not shown), a digital-analog conversion circuit, a buffer circuit, and the like. The digital image signal input from the outside is serial-parallel converted based on a control signal, and a desired analog signal is converted. Convert to signal voltage and output. The scanning line driving circuit 45 includes a shift register, a buffer circuit, and the like (not shown), and sequentially transfers and outputs scanning pulses based on a control signal input from the outside.
Further, the counter substrate 34 includes a glass substrate, and a counter electrode made of a color filter layer (not shown) and ITO is provided on the glass substrate.
[0018]
On the other hand, the second liquid crystal display panel 50 is configured as a transflective liquid crystal display panel having a rectangular effective display area 51 and capable of color display. More specifically, the second liquid crystal display panel 50 is held by a rectangular array substrate 53 and a counter substrate 54 which are arranged to face each other with a predetermined cell gap therebetween, and an alignment film is interposed between these substrates. And a liquid crystal layer 55. The array substrate 53 and the counter substrate 54 are bonded to each other by a sealing material 56. Further, rectangular polarizing plates 57 and 58 are attached to the outer surfaces of the array substrate 53 and the counter substrate 54, respectively, and are arranged so that their polarization axes are orthogonal to each other.
[0019]
Here, the transflective liquid crystal display panel is, for example, a pixel electrode disposed on the array substrate 53 is made of a reflective metal film such as Al, and an opening is provided in a part of the pixel electrode, whereby the back surface of the array substrate 53 The transmission mode that controls transmission / non-transmission of light from the light source and the reflection mode that uses light reflected by the pixel electrode are combined. In addition to this, a selective reflection film made of a cholesteric liquid crystal film or the like may be provided on the back surface side of the array substrate 53 so that the transmission mode and the reflection mode are combined.
[0020]
In addition, the array substrate 53 is configured similarly to the array substrate 33 of the first liquid crystal display panel 30 except for the relay wiring. That is, the array substrate 53 has a glass substrate, on which a signal line 60 and a scanning line 61 arranged in a matrix, a TFT 62 using a polycrystalline silicon film in the channel region, a pixel electrode 63, A signal line driving circuit 64 and a scanning line driving circuit 65 are provided. The drive circuits 64 and 65 are formed on the glass substrate in the same process as the TFT 62.
[0021]
As shown in FIGS. 3 and 4, the signal line driving circuit 44 and the scanning line driving circuit 45 of the first liquid crystal display panel 30 configured as described above are provided via a flexible wiring board 48 that functions as a first connection cable. And electrically connected to the control circuit board 52. The control circuit board 52 is connected to the device main body 10 side through a flexible wiring board 66.
[0022]
The signal line driving circuit 64 and the scanning line driving circuit 65 of the second liquid crystal display panel 50 are connected to the relay wiring 47 of the first liquid crystal display panel 30 via the flexible wiring board 68 that functions as a second connection cable. The relay wiring 47 and the flexible wiring board 48 are electrically connected to the control circuit board 52.
[0023]
The control circuit board 52 has a timing and data arrangement corresponding to the first and second liquid crystal display panels 30 and 50 based on a digital image signal, a system clock, and a reference voltage supplied from the device main body 10 side of the personal computer. A digital image signal having an order and the like, and various horizontal clock signals, vertical clock signals, horizontal start signals, vertical start signals, enable signals and the like necessary for driving the first and second liquid crystal display panels 30 and 50 Generate a control signal. Further, in addition to these logic systems, the control circuit board 52 has a voltage required for driving based on a reference voltage, for example, a 3V reference voltage to a −10V gate pulse off level, and a + 20V gate pulse on level. , A power supply system for generating various voltages such as an analog signal voltage of 0 to 6V.
[0024]
As shown in FIG. 3, the light source unit 70 exits from the rectangular light guide plate 72 corresponding to the array substrates 33, 53, the tubular light source 73 disposed along one side of the light guide plate 72, and the tubular light source 73. And a reflector 74 for introducing light into the light guide plate. Both opposing surfaces of the light guide plate 72 constitute a light emitting surface, and an optical film (not shown) is provided on each light emitting surface in order to improve luminance and improve luminance uniformity.
[0025]
The first and second liquid crystal display panels 30 and 50 are provided back to back with the light guide plate 72 in between, and the array substrates 33 and 53 are adjacent to and opposed to the light emitting surface of the light guide plate 72, respectively. The first and second liquid crystal display panels 30 and 50, the light source unit 70, and the control circuit board 52 are held while being sandwiched between the display housings 22.
[0026]
When housed in the display housing 22, the deflection plate 38 of the first liquid crystal display panel 30 is positioned to face the rectangular opening 22 a formed in the front wall of the display housing, and the second liquid crystal display panel The 50 deflection plates 58 are positioned to face the rectangular opening 22b formed in the back wall of the display housing.
[0027]
According to the personal computer configured as described above, as shown in FIG. 1, by operating the computer with the display unit 12 rotated to the open position, the first and second liquid crystal display panels 30, 50 can be used to display two screens simultaneously. Thereby, an image can be visually recognized from both the front and back sides of the display unit 12. In this case, the same image may be displayed on both the first and second liquid crystal display panels 30 and 50, or different images may be displayed. Further, an image may be selectively displayed on only one of the first and second liquid crystal display panels 30 and 50.
[0028]
Further, according to the personal computer, as shown in FIG. 2, even when the display unit 12 is closed to the closed position, an image can be displayed using the second liquid crystal display panel 50. It becomes possible to use in the form. In the present embodiment, by using the second liquid crystal display panel 50 as a transflective liquid crystal display panel, it is possible to improve the luminance by effectively using external light. At this time, it is desirable that the operation of the first liquid crystal display panel 30 is stopped and not displayed.
[0029]
Further, according to the display unit 12, the second liquid crystal display panel 50 is connected to the control circuit board 52 via the relay wiring 47 formed on the array substrate 33 of the first liquid crystal display panel 30. Then, both the first liquid crystal display panel 30 and the second liquid crystal display panel 50 can be controlled by the image control signal output from the single control circuit board 52. At the same time, a long flexible printed circuit board for connecting the control circuit board 52 and the second liquid crystal display panel 50 can be omitted. Accordingly, the number of parts can be reduced, and the display unit 12 can be reduced in thickness and weight. As a result, the entire personal computer can be reduced in thickness and weight, and the manufacturing cost can be reduced.
[0030]
Furthermore, according to the present embodiment, by using the common light source unit 70 as the backlight of the first and second liquid crystal display panels 30 and 50, the number of parts can be reduced and the display unit 12 can be made thinner and more effective. The weight can be reduced, and at the same time, the manufacturing cost can be reduced.
[0031]
Next explained is an image display apparatus according to the second embodiment of the invention.
As shown in FIG. 5, according to the present embodiment, the first and second liquid crystal display panels 30 and 50 are arranged side by side in the same plane, and are further arranged on a common light source unit 70. And the 1st and 2nd liquid crystal display panels 30 and 50 are comprised similarly to 1st Embodiment mentioned above.
[0032]
The signal line driving circuit and the scanning line driving circuit of the first liquid crystal display panel 30 are electrically connected to the control circuit board 52 via the flexible wiring board 48. The signal line driving circuit and the scanning line driving circuit of the second liquid crystal display panel 50 are connected to the relay wiring of the first liquid crystal display panel 30 through the flexible wiring board 68. The relay wiring 47 and the flexible wiring board 48 are connected to the second liquid crystal display panel 50. And is electrically connected to the control circuit board 52.
[0033]
The light source unit 70 includes a rectangular light guide plate 72 having a size corresponding to two liquid crystal display panels, a tubular light source 73 disposed along the long side of the light guide plate 72, and a light source unit 73. And a reflector 74 for introducing the light into the light guide plate. One surface of the light guide plate 72 constitutes a light emitting surface, and the first and second liquid crystal display panels 30 and 50 are disposed on the light emitting surface via an optical film (not shown).
[0034]
In the second embodiment, other configurations are the same as those of the first embodiment described above, and the same reference numerals are given to the same portions, and detailed description thereof is omitted. In the second embodiment configured as described above, both the first liquid crystal display panel 30 and the second liquid crystal display panel 50 are controlled by the image control signal output from the single control circuit board 52. In addition, the flexible printed circuit board for connection can be shortened and the light source unit can be shared. Thereby, it is possible to obtain an image display device capable of displaying a plurality of screens and capable of reducing the manufacturing cost and reducing the thickness and weight.
[0035]
The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. For example, the image display device according to the present invention is not limited to a display unit of a personal computer but can be applied to various other electronic devices such as a mobile phone and can also be used as a single image display device. For example, when the display unit according to the first embodiment described above is applied to a foldable mobile phone that can be opened and closed, information can be obtained using the first or second display panel both when closed and when it is opened. Can be displayed, and the convenience of the mobile phone can be improved.
[0036]
The number of liquid crystal display panels is not limited to two, and three or more liquid crystal display panels may be connected. In this case, the second liquid crystal display panel is connected via a relay wiring formed on the array substrate of the first liquid crystal display panel. Connected to the control circuit board, and the third liquid crystal display panel is connected to the control circuit board via the relay wiring formed on the array substrates of the first and second liquid crystal display panels. The
[0037]
The display panel used in the present invention is not limited to a liquid crystal display panel, and a self-luminous display panel such as an organic EL panel may be used.
[0038]
In the above-described embodiment, the TFT, the signal line driving circuit, and the scanning line driving circuit are formed integrally with a semiconductor element using a polycrystalline silicon film as an active layer. The signal line driver circuit and the scan line driver circuit may be formed using a circuit board.
[0039]
Further, part or all of the signal line driver circuit and the scanning line driver circuit may be configured using a chip-on-glass (COG) technique in which a driver IC chip is directly mounted on a substrate. In this case, by disposing the drive circuit on the substrate, the number of electrical connections between the liquid crystal display panel and the outside can be reduced, and the external circuit can be configured in a small size, thereby further reducing the size of the display unit. It is effective in achieving the conversion.
[0040]
【Effect of the invention】
As described above in detail, according to the present invention, it is possible to provide an image display device capable of displaying a plurality of screens and capable of reducing the manufacturing cost, reducing the thickness, and reducing the weight, and an electronic apparatus including the image display device.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a personal computer according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a state in which a display unit of the personal computer is closed.
3 is a cross-sectional view of the display unit along line AA in FIG.
4A and 4B are a plan view and a side view showing a liquid crystal display panel of the display unit.
FIG. 5 is a perspective view showing an image display device according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Main body 12 ... Display unit 22 ... Display housing 30 ... 1st liquid crystal display panel 50 ... 2nd liquid crystal display panel 32, 51 ... Display area 33, 53 ... Array substrate 34, 54 ... Opposite substrate 35, 55 ... Liquid crystal layer 40, 60 ... signal lines 41, 61 ... scanning lines 44, 64 ... signal line driving circuits 45, 65 ... scanning line driving circuits 47 ... relay wirings 48, 68 ... flexible printed circuit board 52 ... control circuit board 70 ... light source unit 72 ... Light guide plate 73 ... Tubular light source 74 ... Reflector

Claims (4)

A first liquid crystal display panel having a display region in which display pixels are arranged in a matrix , a driving circuit for signal lines and scanning lines , and an array substrate on which relay wiring extending along a side edge is formed;
A second liquid crystal display panel having a display region in which display pixels are arranged in a matrix and an array substrate on which drive circuits for signal lines and scanning lines are formed;
A control circuit board for controlling the first and second liquid crystal display panels ;
A first connection cable for connecting the drive circuit of the first liquid crystal display panel and one end of the relay wiring to the control circuit board ;
A second connection cable for connecting the other end of the relay wiring and the drive circuit of the second liquid crystal display panel ;
An image comprising: the first liquid crystal display panel and the second liquid crystal display panel facing each other via the second connection cable; and a light source unit interposed between the opposed liquid crystal display panels. Display device. The light source unit includes a light guide plate having a pair of opposed light emission surfaces, and a light source having a reflector disposed along one side edge of the light guide plate, and the first and second liquid crystal display panels. The image display device according to claim 1 , wherein the image display device is disposed so as to be opposed to each other with the light guide plate interposed therebetween and to be opposed to the light emitting surfaces. A device body provided with a data input unit;
A housing that is pivotable between a closed position that covers the data input unit and an open position that opens the input unit with respect to the device body, and is formed on a surface corresponding to the data input unit. A housing having a first opening and a second opening formed on the opposite surface;
The display area of the first liquid crystal display panel disposed in the housing faces the first opening, and the display area of the second liquid crystal display panel disposed in the housing is the second opening. An electronic display device comprising: the image display device according to claim 1, which is opposed to the electronic device. 4. The electronic apparatus according to claim 3, wherein the first liquid crystal display panel is constituted by a light transmissive liquid crystal display panel, and the second liquid crystal display panel is constituted by a transflective liquid crystal display panel. .

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