JP2007334224A - Liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display having excellent display performance. <P>SOLUTION: The liquid crystal display is provided with: an array substrate having a substrate, a plurality of scanning line groups having a plurality of first scanning lines 22 and a plurality of second scanning lines 23, a plurality of signal line groups having a plurality of signal lines 25 and a plurality of pixel groups including a plurality of pixel parts 12 each provided with a transmission pixel part 13 and a reflection pixel part 14; a counter substrate; a liquid crystal layer; a color filter; and a driving part giving independent signals to the first scanning lines and the signal lines to perform first driving of the transmission pixel parts or simultaneously giving the same signal to the second scanning lines for every scanning line group and simultaneously giving the same signal to the signal lines for every signal line group to perform second driving of the reflection pixel parts. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid crystal display device.

  In recent years, liquid crystal display devices have been widely used as display devices. Since the liquid crystal display device is small and light, it is used as a display device for a portable electronic device such as a mobile phone or an electronic camera. In general, a liquid crystal display device includes an array substrate, a counter substrate disposed to face the array substrate, and a liquid crystal layer sandwiched between the two substrates.

  For example, the electronic camera includes a first liquid crystal display device that performs a first display and a second liquid crystal display device that performs a second display. The first liquid crystal display device is a reflection-type liquid crystal display device for monochrome display, and is used for displaying identification information such as information on photographing modes. The second liquid crystal display device is a transmissive liquid crystal display device for color display, and is used to display an acquired image.

  The first liquid crystal display device includes a front light unit. In the dark, the first liquid crystal display device operates the front light unit and displays the identification information. The first liquid crystal display device performs segment display and displays characters and symbols. Therefore, it is possible to obtain a first liquid crystal display device that can reduce power consumption, does not require a clock signal, and can display characters and the like clearly and clearly. The second liquid crystal display device has a color filter and a plurality of pixels. Therefore, it is possible to obtain a second liquid crystal display device that is high definition and capable of multicolor display.

A technique for performing the first display and the second display with a single liquid crystal display device is also known (see, for example, Patent Document 1). In this case, the first display is performed in one of the divided areas, and the second display is performed in the other area.
JP 2005-173565 A

  Since the electronic camera has two liquid crystal display devices, there is a risk that the manufacturing cost will increase and the product price will increase. Moreover, there is a risk of increasing the size of the apparatus. On the other hand, since the mobile phone has one liquid crystal display device, there is no fear that the product price will increase and the device size will increase.

However, the first display and the second display cannot be displayed in full screen. For this reason, information to be displayed is limited in both the first display and the second display.
The present invention has been made in view of the above points, and an object thereof is to provide a liquid crystal display device having excellent display performance.

In order to solve the above-described problem, a liquid crystal display device according to an aspect of the present invention includes:
A substrate, a plurality of first scan lines and a plurality of second scan lines, a plurality of scan line groups provided side by side on the substrate, and a plurality of crossing the first scan line and the second scan line A plurality of signal lines arranged side by side on the substrate, and each transmission line unit connected to each first scanning line of each scanning line group and each signal line of each signal line group, And a plurality of pixel portions each having a reflection pixel portion connected to each second scanning line of each scanning line group and each signal line of each signal line group, and at an intersection of the scanning line group and the signal line group An array substrate having a plurality of pixel groups provided; and
A counter substrate disposed opposite to the array substrate with a gap;
A liquid crystal layer sandwiched between the array substrate and the counter substrate;
A color filter provided on any one of the array substrate and the counter substrate overlaid on each transmissive pixel portion, and having a colored layer of a plurality of colors;
An independent signal is given to the plurality of first scanning lines and an independent signal is given to the plurality of signal lines to drive the plurality of transmissive pixel portions in the first drive, or the plurality of first scanning lines are provided for each scanning line group. And a driving unit that simultaneously applies the same signal to the two scanning lines and simultaneously applies the same signal to the plurality of signal lines for each of the signal line groups to drive the plurality of reflective pixel units in a second manner.

In addition, a liquid crystal display device according to another aspect of the present invention includes:
An array substrate having a substrate and a plurality of pixel portions provided on the substrate and each including a transmissive pixel portion and a reflective pixel portion;
A counter substrate disposed opposite to the array substrate with a gap;
A liquid crystal layer sandwiched between the array substrate and the counter substrate;
A color filter provided on any one of the array substrate and the counter substrate overlaid on each transmissive pixel portion, and having a colored layer of a plurality of colors;
A drive unit that selects and drives any one of the plurality of transmission pixel units and the plurality of reflection pixel units of the plurality of pixel units.

  According to the present invention, a liquid crystal display device having excellent display performance can be provided.

Hereinafter, a liquid crystal display device according to an embodiment of the present invention will be described in detail with reference to the drawings. The liquid crystal display device is a transflective liquid crystal display device.
As shown in FIGS. 1 and 2, the liquid crystal display device includes a liquid crystal display panel P. The liquid crystal display panel P includes an array substrate 1, a counter substrate 2 disposed to face the array substrate, and a liquid crystal layer 3 sandwiched between the two substrates.

  The array substrate 1 includes, as a transparent insulating substrate, for example, a glass substrate 1s and an array pattern 1p formed on the glass substrate 1s and having a multilayer wiring structure. The array substrate 1 has a plurality of columnar spacers 9 formed on the array pattern 1p as spacers. In addition, as described later, the array substrate 1 has an alignment film 1a formed on the array pattern 1p.

  The counter substrate 2 includes, for example, a glass substrate 2s and a counter pattern 2p formed on the glass substrate 2s as a transparent insulating substrate. In addition, although mentioned later, the opposing substrate 2 has the orientation film 2a formed on the opposing pattern 2p.

  A gap between the array substrate 1 and the counter substrate 2 is held by a columnar spacer 9. The array substrate 1 and the counter substrate 2 are bonded together by a sealing material 4 disposed at the peripheral edge of both the substrates. A liquid crystal injection port 5 is formed in the sealing material 4, and the liquid crystal injection port 5 is sealed with a sealing material 6.

  In addition, the liquid crystal display device has a backlight unit 8 disposed on the outer surface side of the array substrate 1. The backlight unit 8 includes a light guide plate 8a disposed to face the array substrate 1, and a light source 8b and a reflection plate 8c disposed to face one side edge of the light guide plate.

Next, the array substrate 1 will be described in detail.
As shown in FIGS. 2, 3 and 4, the array substrate 1 has a display region Rd. The array pattern 1p has a plurality of pixel groups 11 provided in a matrix in the display region Rd. Each pixel group 11 has a plurality of pixel portions 12. In this embodiment, each pixel group 11 has twelve pixel portions 12.

  In the first direction d1, the plurality of pixel units 12 are arranged in a straight line. In the second direction d2, the odd-numbered plurality of pixel portions 12 and the even-numbered plurality of pixel portions 12 are aligned with each other in the first direction d1. Outside the display region Rd, a scanning line driving circuit 15, a signal line driving circuit 16, and an auxiliary capacitance line driving circuit 17 are provided on the glass substrate 1s. Note that the scanning line driving circuit 15, the signal line driving circuit 16, the auxiliary capacitance line driving circuit 17, and the like form a driving unit 20.

  The array pattern 1p includes a plurality of scanning line groups 21, a plurality of signal line groups 24, and a plurality of auxiliary capacitance lines 26. Each scanning line group 21 has a plurality of first scanning lines 22 and a plurality of second scanning lines 23. Each signal line group 24 has a plurality of signal lines 25. The first scanning line 22, the second scanning line 23, the signal line 25, and the auxiliary capacitance line 26 are formed on the glass substrate 1s including the display region Rd.

  The first scanning line 22 and the second scanning line 23 are connected to the scanning line driving circuit 15 and extend in the first direction d1. The signal line 25 is connected to the signal line driving circuit 16 and extends in a second direction d2 orthogonal to the first direction d1. The auxiliary capacitance line 26 is connected to the auxiliary capacitance line driving circuit 17 and extends in the first direction d1 like the first scanning line 22 and the second scanning line 23.

  As shown in FIGS. 5, 6 and 7, the array pattern 1 p has a plurality of first polarity switching lines 27 and a plurality of second polarity switching lines 28. The first polarity switching line 27 and the second polarity switching line 28 are formed on the glass substrate 1s including the display region Rd. The first polarity switching line 27 and the second polarity switching line 28 are connected to the scanning line driving circuit 15 and extend in the first direction d1.

  Here, in each pixel group 11, any one of the six pixel units 12 arranged in the first direction d <b> 1 has an SRAM 80 as a static memory unit. For this reason, two pixel portions 12 for each pixel group 11 have SRAMs 80. In each pixel group 11, the SRAM 80 is connected to the other five pixel units 12 arranged in the first direction d <b> 1 in the pixel unit 12 having the SRAM 80.

  Next, in FIG. 4, when the pixel portion having the SRAM 80 is the pixel portion 12 indicated by the arrow A, the pixel portion 12 indicated by the arrow A1 will be described in detail with reference to FIG. Further, the pixel portion 12 indicated by an arrow A2 in FIG. 4 will be described in detail with reference to FIG. 6 as a representative of the pixel portion formed without the SRAM 80.

  As shown in FIGS. 4, 5, and 7, the pixel unit 12 including the SRAM 80 includes a transmissive pixel unit 13 and a reflective pixel unit 14. The transmissive pixel portion 13 includes a TFT 30 as a first switching element, a first electrode 40, and an auxiliary capacitance element 50.

  The TFT 30 is connected to the first scanning line 22 and the signal line 25. The TFT 30 is provided near the intersection of the first scanning line 22 and the signal line 25. A first node n1 of the TFT 30 is connected to the first electrode 40. The first node n1 is connected to the auxiliary capacitance element 50 formed by the auxiliary capacitance line 26. When the TFT 30 is driven by a first scanning signal (hereinafter referred to as a first scanning voltage) from the first scanning line 22, the TFT 30 supplies a driving voltage (hereinafter referred to as a driving voltage) on the signal line 25 to the first electrode 40. It is formed to be applied to. The first electrode 40 is formed of a transparent conductive film such as ITO (indium tin oxide).

  Here, the auxiliary capacitance element 50 will be described. The capacity of the auxiliary capacitive element 50 is charged / discharged by the drive voltage applied to the first electrode 40. When the auxiliary capacitive element 50 holds the drive voltage by this charge / discharge, even when the TFT 30 is non-conductive during driving, the first electrode 40 and the later-described electrode are driven by the drive voltage held by the auxiliary capacitive element. The potential difference between the opposing electrodes 2e is maintained.

  The reflective pixel unit 14 includes a TFT 60 as a second switching element, an SRAM 80, an SRAM drive circuit 70 as a static memory unit drive circuit, and a second electrode 90.

  The TFT 60 is connected to the second scanning line 23 and the signal line 25. The TFT 60 is provided in the vicinity of the intersection of the second scanning line 23 and the signal line 25. The second node n2 of the TFT 60 is connected to the third node n3 of the SRAM drive circuit 70. The second node n2 is connected to the second electrode 90 via a contact wiring. The TFT 60 is formed to apply a driving voltage on the signal line 25 to the second electrode 90 when driven by a second scanning signal (hereinafter referred to as a second scanning voltage) from the second scanning line 23. .

  The second electrode 90 is formed of a thin film of a material that reflects light, such as aluminum as a metal. The second electrode 90 is provided in a non-conductive state with the first electrode 40 and surrounds the first electrode 40. Here, the second scanning line 23 and the signal line 25 are arranged so as to partition the pixel portion 12. The second electrode 90 is provided in a region surrounded by two adjacent second scanning lines 23 and two adjacent signal lines 25.

  The SRAM 80 includes a first inverter 81, a second inverter 82, and a TFT 83 as a switching element for controlling a current that loops through these inverters. In this embodiment, the TFT 83 is a p-type TFT, and its gate electrode is electrically connected to the second scanning line 23.

  When the scanning voltage from the second scanning line 23 is at the H (high) level, the TFT 83 is not conductive during the period in which the TFT 30 is conductive. The TFT 83 becomes conductive when the scanning voltage is at the L (low) level.

  The sixth node n6 is connected to the input terminal of the first inverter 81, and the output terminal of the first inverter 81 is connected to the input terminal of the second inverter 82 via the seventh node n7. The output terminal of the second inverter 82 is connected to the input terminal of the first inverter 81 via the TFT 83 controlled by the scanning voltage.

  The SRAM drive circuit 70 includes a TFT 71 as a first drive unit and a TFT 72 as a second drive unit. In this embodiment, the TFT 71 and the TFT 72 are n-type TFTs. The TFT 71 and the TFT 72 are formed in the same manner as the TFT 60. The gate electrode of the TFT 71 is electrically connected to the first polarity switching line 27. The gate electrode of the TFT 72 is electrically connected to the second polarity switching line 28.

  The TFT 71 is connected to the third node n3 and the sixth node n6, and the TFT 72 is connected to the third node n3 and the seventh node n7, respectively. As described above, the TFT 71 and the TFT 72 are connected to the second electrode 90 and the SRAM 80 in parallel with each other. Here, the SRAM 80 is connected to the six second electrodes 90 of the six reflective pixel units 14 via the SRAM driving circuit 70 and the connection wiring 29.

  The SRAM drive circuit 70 controls the electrical connection between the six second electrodes 90 and the SRAM 80, and also contributes to the control of the output polarity of the drive voltage held in the SRAM. In the still image display mode, these TFTs 71 and 72 are controlled by, for example, alternately applying an H level voltage to the first polarity switching line 27 and the second polarity switching line 28 every frame. Here, one frame is a time period for sequentially scanning all the reflective pixel units 14 and scanning the same reflective pixel unit 14 again.

  As shown in FIGS. 4, 6, and 7, the pixel portion 12 formed without the SRAM 80 includes a transmissive pixel portion 13 and a reflective pixel portion 14. The transmissive pixel portion 13 is formed in the same manner as the transmissive pixel portion of the pixel portion 12 having the SRAM 80. The reflective pixel unit 14 is formed without providing the SRAM driving circuit 70 and the SRAM 80, and is formed in the same manner as the reflective pixel unit of the pixel unit 12 having the SRAM 80. As described above, the second electrode 90 is connected to the SRAM 80 of the other pixel unit 12 via the connection wiring 29.

  As shown in FIGS. 4 to 7, the TFT 30, the auxiliary capacitance element 50, the TFT 60, the SRAM drive circuit 70 and the SRAM 80 are more preferably formed below the second electrode 90. Thus, the aperture ratio of the transmissive display region overlapping the first electrode 40 can be increased while maintaining the area of the reflective display region overlapping the second electrode 90.

  As shown in FIG. 7, in the counter substrate 2, the counter pattern 2p includes a color filter 7 having a plurality of colored layers of red (R), green (G), and blue (B), a light shielding portion 7s, and an insulating layer. A film 7i and a counter electrode 2e are provided. The color filter 7 overlaps the first electrode 40 and is provided in the transmissive display area. The color filter 7 protrudes toward the array substrate 1 side.

  The insulating film 7 i is provided around the color filter 7. The insulating film 7i overlaps at least the second electrode 90 and is provided in the reflective display region. The insulating film 7 i protrudes closer to the array substrate 1 than the color filter 7, and the layer thickness of the liquid crystal layer facing the second electrode 90 is made thinner than the layer thickness of the liquid crystal layer facing the first electrode 40.

  The light shielding part 7 s is provided along the gap between the first electrode 40 and the second electrode 90 and the peripheral edge of the second electrode 90. The counter electrode 2e is provided so as to overlap at least the display region Rd, and is provided on the glass substrate 2s, the color filter 7, the insulating film 7i, and the light shielding portion 7s. The alignment film 2a is formed on the counter electrode 2e.

  Here, the drive unit 20 selects and drives any one of the plurality of transmission pixel units 13 and the plurality of reflection pixel units 14. Needless to say, the drive unit 20 does not drive the plurality of transmission pixel units 13 and the plurality of reflection pixel units 14 at the same time.

Next, the scanning line driving circuit 15 will be described.
As shown in FIG. 8, the scanning line driving circuit 15 has a plurality of common wirings 18c. The second scanning line 23 of each scanning line group 21 is connected to one common wiring 18c. The second scanning line 23 of each scanning line group 21 is electrically connected.

Next, the signal line driving circuit 16 will be described.
As shown in FIG. 9, the signal line driving circuit 16 has an NGAT circuit 19 as a first switching circuit. The NGAT circuit 19 includes a plurality of switching element groups 19a, a plurality of common wirings 19c, a first switching wiring 19d, a second switching wiring 19e, a third switching wiring 19f, a fourth switching wiring 19g, a fifth switching wiring 19h, And a sixth switching wiring 19i.

  The switching element group 19a includes a TFT 19b as a plurality of switching elements. In this embodiment, the switching element group 19a has six TFTs 19b. For each switching element group 19a, the six TFTs 19b are connected to one common wiring 19c. For each switching element group 19a, the gate electrode of each TFT 19b is connected to one of the first switching wiring 19d to the sixth switching wiring 19i, and is connected to a different switching wiring.

  The NGAT circuit 19 is connected to a plurality of signal lines 25 and can be switched for each signal line group 24 to a state in which independent signals or simultaneously the same signals are given to the plurality of signal lines 25.

Next, display modes of the liquid crystal display device described above will be described. The liquid crystal display device is a normally black mode in which black display is performed when no voltage is applied to the liquid crystal layer 3.
First, a transmissive color display mode (hereinafter referred to as a transmissive display mode) in which the transmissive pixel unit 13 is first driven to obtain a high-resolution image will be described. Here, the driving unit 20 gives independent scanning voltages to the plurality of first scanning lines 22 and gives independent driving voltages to the plurality of signal lines 25 to drive the plurality of transmissive pixel units 13 in the first drive.

  First, the scanning line driving circuit 15 sequentially applies the scanning voltage to the plurality of first scanning lines 22 every frame period. Each first scanning line 22 is maintained at the H level or the L level for one horizontal scanning period by the scanning voltage. The signal line driving circuit 16 applies a driving voltage for one row whose level is inverted every horizontal scanning period to the plurality of signal lines 25. At this time, since the NGAT circuit 19 switches on / off of the TFT 19 b, the drive voltage given to the common wiring 19 c is applied to any one of the signal lines 25 for each signal line group 24.

  The TFT 30 is turned on (conducted) by the H level scanning voltage from the first scanning line 22, takes in the driving voltage applied to the signal line 25, and applies it to the first electrode 40. Since the second scanning line 23 is maintained at the L level, the TFT 60 is turned off (non-conducting). When the TFT 30 is turned off after one horizontal scanning period and the first electrode 40 is in an electrically floating state, the drive voltage is held by the auxiliary capacitance element 50 until the TFT 30 is turned on again. Thereby, image display is performed using the voltage held by the auxiliary capacitive element 50.

  In the transmissive display mode, the picture element is formed by three pixel portions 12 arranged in the first direction d1. More specifically, the picture element includes a transmissive pixel portion 13 having a first electrode 40 superimposed on a red colored layer, a transmissive pixel portion 13 having a first electrode 40 superimposed on a green colored layer, and a blue pixel. It is formed by the transmissive pixel portion 13 having the first electrode 40 overlapped with the colored layer.

  Next, a reflective monochrome display mode (hereinafter referred to as a reflective display mode) in which the reflective pixel unit 14 is second driven to obtain a low resolution image will be described. Here, the driving unit 20 simultaneously applies the same scanning voltage to the plurality of second scanning lines 23 for each scanning line group 21 and simultaneously applies the same driving voltage to the plurality of signal lines 25 for each signal line group 24. Then, the plurality of reflective pixel portions 14 are driven in the second manner.

  The SRAM 80 has a function of holding the second drive. In this embodiment, the reflective display mode is also a still image display mode because an image is displayed using the SRAM 80.

  When shifting to the reflective display mode, first, the first polarity switching line 27 is maintained at the H level and the second polarity switching line 28 is maintained at the L level during the still image writing period which is the first one frame period. As described above, while maintaining the H level or the L level, the scanning line driving circuit 15 sequentially applies the scanning voltage to the second scanning line 23 via the common wiring 18c. In the above state, the still image drive voltage is applied to the signal line 25 every horizontal scanning period in this frame period.

  At this time, since the NGAT circuit 19 simultaneously switches on / off of the six TFTs 19b for each switching element group 19a, the same drive voltage is applied to the six signal lines 25 for each signal line group 24.

  In the subsequent still image holding period, an H level voltage is alternately applied to the first polarity switching line 27 and the second polarity switching line 28 every frame period in order to invert the output polarity of the SRAM 80.

  As described above, in the first frame period corresponding to the still image writing period in the still image display mode, the H level voltage is applied to the first polarity switching line 27 and the first polarity switching line is maintained at the H level. The driving voltage corresponding to the binary still image information is applied to the second electrode 90 via the TFT 60 which is turned on (conductive). At this time, in the reflective pixel portion 14 having the SRAM 80, the drive voltage is applied to the SRAM 80 via the TFT 71. Since the first scanning line 22 is maintained at the L level, the TFT 30 is turned off (non-conducting).

  In the still image holding period, for example, when an L level voltage is applied to the first polarity switching line 27 and an H level voltage is applied to the second polarity switching line 28, the drive voltage described above is inverted by the first inverter 81, An output drive voltage is applied to the six second electrodes 90 via the TFT 72 and the connection wiring 29. As described above, display characteristics can be stabilized by alternately applying H level and L level voltages to the second electrode 90 during the still image display mode.

  In the reflective display mode, the picture element is formed by twelve pixel portions 12 of the pixel group 11. More specifically, the picture element is formed by twelve reflective pixel portions 14 of the pixel group 11.

  Here, the inventors of the present application have described the contrast, reflectance, luminance, color reproducibility, power consumption of the liquid crystal display device in the case of the display mode, screen size, number of pixels, pixel pitch, and number of colors as shown in FIG. And the input voltage was investigated. Various characteristics of the investigated liquid crystal display device are as shown in the figure.

  Next, as shown in FIG. 11, the gradation, the number of picture elements, and the picture element pitch for the transmissive display mode and the reflective display mode of the liquid crystal display device will be described. The gradation, the number of picture elements, and the picture element pitch are as shown in the figure.

  According to the liquid crystal display device configured as described above, each pixel group 11 includes a plurality of pixel units 12, and each pixel unit 12 includes a transmissive pixel unit 13 and a reflective pixel unit 14. Since the driving unit 20 includes the scanning line driving circuit 15 and the signal line driving circuit 16 including the NGAT circuit 19, the driving unit 20 is switched to either the transmissive pixel unit 13 or the reflective pixel unit 14 and driven independently. The image can be displayed by switching to either the transmissive display mode or the reflective display mode.

  In the transmissive display mode, a favorable black display is obtained in the reflective display area, so that it is possible to prevent a reduction in the saturation of the image. In the reflective display mode, high-luminance reflected light can be obtained in the reflective display area where the color filter 7 is not provided, so that it is possible to prevent a decrease in image brightness. By switching the display mode from the transmissive display mode to the reflective display mode, the area of the picture element can be enlarged.

  By using the transmissive display mode, a color image with high resolution can be displayed. By using the reflective display mode, power consumption can be reduced, a clock signal can be eliminated, and an image in which characters and the like are large and clear can be displayed.

  Even an electronic device such as an electronic camera and a mobile phone on which one liquid crystal display device is mounted can be switched between transmissive display and reflective display. Since it is not necessary to mount two or more liquid crystal display devices on the electronic device, it is possible to suppress an increase in manufacturing cost and, in turn, an increase in product price. Moreover, the enlargement of an electronic device can be suppressed.

  In addition, since the SRAM driving circuit 70 and the SRAM 80 are formed on the glass substrate 1s in the display region Rd and are formed of the same material as the TFT 30 and the TFT 60, the manufacturing cost can be suppressed, and the liquid crystal can be suppressed. An increase in the size of the display panel can be suppressed.

In addition, both the transmissive display and the reflective display, the liquid crystal display device can display an image over the entire screen. Therefore, transmissive display and reflective display can be performed without limiting the information to be displayed.
As described above, a resolution can be controlled and a liquid crystal display device with excellent display performance can be obtained.

Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.
For example, as shown in FIG. 12, the pixel units 12 may be arranged in a straight line in each of the first direction d1 and the second direction d2.

As shown in FIG. 13, the scanning line driving circuit 15 may have an NGAT circuit 18 as a second switching circuit. Hereinafter, the NGAT circuit 18 will be described.
The NGAT circuit 18 includes a plurality of switching element groups 18a, a plurality of common wirings 18c, a first switching wiring 18d, and a second switching wiring 18e.

  Each switching element group 18a includes a TFT 18b as a plurality of switching elements. In this embodiment, the switching element group 18a has two TFTs 18b. For each switching element group 18a, the two TFTs 18b are connected to one common wiring 18c. For each switching element group 18a, the gate electrode of one TFT 18b is connected to the first switching wiring 18d, and the gate electrode of the other TFT 18b is connected to the second switching wiring 18e.

  The NGAT circuit 18 is connected to the plurality of second scanning lines 23 and can be switched to a state in which independent signals or the same signal is simultaneously given to the plurality of second scanning lines 23 for each scanning line group 21. By providing the NGAT circuit 18, reflection display can be performed without increasing the area of the picture element.

  Further, the first switching circuit is not limited to the NGAT circuit 19, and the second switching circuit 18 is not limited to the NGAT circuit 18. The number of pixel portions 12 in the pixel group 11 is not limited to twelve. The drive unit 20 may have any configuration as long as it can select and drive any one of the plurality of transmission pixel units 13 and the plurality of reflection pixel units 14.

1 is a perspective view showing a liquid crystal display panel of a liquid crystal display device according to an embodiment of the present invention. Sectional drawing of the said liquid crystal display device. FIG. 3 is a plan view of the array substrate shown in FIGS. 1 and 2. FIG. 3 is an enlarged plan view showing a part of the array substrate. The figure which showed the equivalent circuit of the pixel part which has SRAM of the said liquid crystal display device. The figure which showed the equivalent circuit of the pixel part formed without providing SRAM of the said liquid crystal display device. Sectional drawing of the pixel part of the said liquid crystal display device. FIG. 3 is a diagram showing a scanning line driving circuit of the liquid crystal display device. FIG. 4 is a diagram showing an NGAT circuit of a signal line driver circuit of the liquid crystal display device. The figure which showed the various characteristics of the said liquid crystal display device with the table | surface. The figure which showed the gradation, the number of picture elements, picture element pitch, and I / F with respect to the transmissive display mode and reflective display mode of the said liquid crystal display device with a table | surface. The top view of the array substrate which shows the modification of the said liquid crystal display device. FIG. 10 is a diagram showing a NGAT circuit of the scanning line driving circuit, which is a modification of the scanning line driving circuit of the liquid crystal display device.

The top view which took out the pixel electrode, the protrusion part, and protrusion of the liquid crystal display device which show the modification of the said liquid crystal display device, and was seen from the counter substrate side.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Array substrate, 1s ... Glass substrate, 2 ... Counter substrate, 2s ... Glass substrate, 3 ... Liquid crystal layer, 7 ... Color filter, 8 ... Backlight unit, 11 ... Pixel group, 12 ... Pixel part, 13 ... Transmission pixel 14, reflection pixel unit, 15 scanning line driving circuit, 16 signal line driving circuit, 18 NGAT circuit, 18 a switching element group, 18 b TFT, 18 c common wiring, 18 d first switching wiring, 18 e ... second switching wiring, 19 ... NGAT circuit, 19a ... switching element group, 19b ... TFT, 19c ... common wiring, 19d ... first switching wiring, 19e ... second switching wiring, 19f ... third switching wiring, 19g ... first 4 switching wiring, 19h: fifth switching wiring, 19i: sixth switching wiring, 20: drive unit, 21: scanning line group, 22: first scanning line, 23: second scanning line, 24: signal line group, 25 ... Shin Line 26, Auxiliary capacitance line, 27 ... First polarity switching line, 28 ... Second polarity switching line, 29 ... Connection wiring, 30 ... TFT, 40 ... First electrode, 50 ... Auxiliary capacitance element, 60 ... TFT, 70 ... SRAM drive circuit, 71 ... TFT, 72 ... TFT, 80 ... SRAM, 81 ... inverter, 82 ... inverter, 83 ... TFT, 90 ... second electrode, P ... liquid crystal display panel, Rd ... display area, d1 ... direction, d2 direction.

Claims (10)

A substrate, a plurality of first scan lines and a plurality of second scan lines, a plurality of scan line groups provided side by side on the substrate, and a plurality of crossing the first scan line and the second scan line A plurality of signal lines arranged side by side on the substrate, and each transmission line unit connected to each first scanning line of each scanning line group and each signal line of each signal line group, And a plurality of pixel portions each having a reflective pixel portion connected to each second scanning line of each scanning line group and each signal line of each signal line group, and at an intersection of the scanning line group and the signal line group An array substrate having a plurality of pixel groups provided; and
A counter substrate disposed opposite to the array substrate with a gap;
A liquid crystal layer sandwiched between the array substrate and the counter substrate;
A color filter provided on any one of the array substrate and the counter substrate overlaid on each transmissive pixel portion, and having a colored layer of a plurality of colors;
An independent signal is given to the plurality of first scanning lines and an independent signal is given to the plurality of signal lines to drive the plurality of transmissive pixel units in the first drive, or the plurality of first scanning lines are provided for each scanning line group. And a driving unit that simultaneously applies the same signal to the two scanning lines and simultaneously applies the same signal to the plurality of signal lines for each of the signal line groups to drive the plurality of reflective pixel units second. Display device. The drive unit is connected to the plurality of signal lines, and the independent signal or the same signal is applied to the plurality of signal lines for each signal line group in correspondence with the first drive and the second drive. With a switching circuit that switches to a state where
The liquid crystal display device according to claim 1, wherein the plurality of second scanning lines are electrically connected to each scanning line group.   The driving unit is connected to the plurality of signal lines, and is supplied with the independent signal or the same signal to the plurality of signal lines for each signal line group corresponding to the first driving and the second driving. A switching circuit for switching to a state; and the plurality of second scanning lines connected to the plurality of second scanning lines, the independent signals or the plurality of second scanning lines corresponding to the first drive and the second drive, The liquid crystal display device according to claim 1, further comprising: another switching circuit that switches to a state in which the same signal is applied.   The plurality of pixel portions are provided in the plurality of transmissive pixel portions, provided in the plurality of first switching elements connected to the first scanning lines and signal lines, and in the plurality of reflective pixel portions, and the second. The liquid crystal display device according to claim 1, further comprising: a plurality of second switching elements connected to the scanning line and the signal line. The plurality of first switching elements are turned on in the first drive and turned off in the second drive,
The liquid crystal display device according to claim 1, wherein the plurality of second switching elements are turned off by the first drive and turned on by the second drive.   The liquid crystal display device according to claim 1, wherein each of the pixel groups includes a static memory unit provided in any one of the plurality of reflective pixel units of each pixel group.   The liquid crystal display device according to claim 1, further comprising a backlight unit that is located on the opposite side of the counter substrate with respect to the array substrate and is disposed to face the array substrate.   The liquid crystal display device according to claim 1, wherein the liquid crystal display device is a normally black mode in which black display is performed in a state where no voltage is applied to the liquid crystal layer. The plurality of pixel units are provided in the plurality of transmissive pixel units, provided in the plurality of first electrodes connected to the plurality of first switching elements, and in the plurality of reflective pixel units, and the plurality of second pixels. A plurality of second electrodes connected to the switching element,
5. The liquid crystal display device according to claim 4, wherein, for each pixel portion, the second electrode surrounds the first electrode and is provided in a non-conductive state with the first electrode. An array substrate having a substrate and a plurality of pixel portions provided on the substrate and each including a transmissive pixel portion and a reflective pixel portion;
A counter substrate disposed opposite to the array substrate with a gap;
A liquid crystal layer sandwiched between the array substrate and the counter substrate;
A color filter provided on any one of the array substrate and the counter substrate overlaid on each transmissive pixel portion, and having a colored layer of a plurality of colors;
A liquid crystal display device comprising: a drive unit that selects and drives any one of the plurality of transmission pixel units and the plurality of reflection pixel units of the plurality of pixel units.

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