JP2008241833A - Electrooptical device, active matrix substrate, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce size of an electrooptical device in an X-direction by eliminating the need for a Y driver in the electrooptical device. <P>SOLUTION: A longitudinal shift register 200 and a latch circuit 300 are provided for each column. Once image data of one picture are stored in transfer unit circuits (register) RY of respective stages of the longitudinal shift register, a latch pulse (YSFT) is made active to latch the image data held in the transfer unit circuits (RY) of the respective stages in a latch element circuit (RL) in parallel. Image data in a Y-direction shift register (200) can be scrolled up and down, circulated, or scrolled laterally. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electro-optical device, an active matrix substrate, and an electronic apparatus.

  An electro-optical device (including a display device such as a liquid crystal device and an EL device, here a liquid crystal device) is selected by a plurality of scanning lines, a plurality of data lines, each of the scanning lines, and each of the data lines. And a pixel array in which pixels are arranged in a matrix. The scanning line is driven by a Y driver, and the data line is driven by an X driver.

  A liquid crystal display panel has an aspect ratio (aspect ratio) of approximately 4: 3, but a wide screen liquid crystal display panel may be 16: 9 (see Patent Document 1).

A liquid crystal device provided with two memories (flip-flops) per pixel has been proposed (see Patent Document 2). However, this liquid crystal device also includes an X driver and a Y driver, and a pixel is selected by a scanning line and a data line.
JP 2004-118217 A JP 2000-148065 A

  When the screen has a horizontally long shape (long in the X direction) like a wide screen liquid crystal device, the scanning line length becomes long. In order to drive the long scanning line at high speed, the Y driver must be arranged on the left side and the right side.

  However, in this case, since the Y driver is arranged on the left and right, the shape is further elongated horizontally, and the area occupied by the Y driver is large, and thus the size of the display panel cannot be denied.

  The present invention has been made based on such considerations, and one of its purposes is to eliminate the need for a Y driver in the electro-optical device and to reduce the size of the electro-optical device in the X direction. .

  (1) According to one aspect of the electro-optical device of the present invention, image data supplied from an X driver arranged along the X direction and the X driver is transferred in the Y direction orthogonal to the X direction. A Y-direction shift register configured by cascade-connecting a plurality of stages of transfer unit circuits, and a transfer unit circuit of each stage provided corresponding to the transfer unit circuit of each stage of the Y-direction shift register. A latch circuit including a plurality of latch element circuits for latching each of the held image data in parallel, and the one-stage transfer unit circuit constituting the Y-direction shift register; One pixel circuit is constituted by the latch element circuit provided corresponding to the transfer unit circuit.

  Image data output from the X driver is sequentially transferred by a Y-direction shift register arranged in the data line direction (Y direction). When an image for one screen is completed, the image data of each pixel is latched. Are latched (stored) in parallel. A new image display method based on frame sequential driving, in which data of each pixel is updated by data transfer using a shift register and parallel latch to a latch element circuit, is employed. Unlike the prior art, it is not necessary to specify a pixel by scanning lines and data lines and write data into the pixel, so that a Y driver is not necessary. In this case, for example, in the case of a reflective liquid crystal device, there is an empty space under the reflective electrode. Therefore, if a transistor constituting a Y-direction shift register or a latch element circuit is arranged in the empty space, the pixel array The occupied area is not particularly increased.

  (2) In another aspect of the electro-optical device of the present invention, the odd-numbered transfer unit circuits constituting the Y-direction shift register are driven by a first transfer clock, and the even-numbered transfer unit circuits are: The image that is driven by a second transfer clock having a phase opposite to that of the first transfer clock and is held in the transfer unit circuit of each stage is included in the latch element circuit of each stage constituting the latch circuit. A latch pulse for latching each of the data in parallel is input, and the first and second transfer clocks and the latch pulse are arranged on the X driver side or sandwich the Y-direction shift register. And generated by a clock circuit arranged on the opposite side of the X driver.

  The transfer clock supplied to the Y-direction shift register and the latch clock supplied to the latch element circuit are generated by the clock circuit. The clock circuit is on the X driver side or on the opposite side of the X driver across the pixel array. It is clarified that it is arranged in That is, since the clock circuit is arranged on the Y direction (vertical direction) side and not arranged in the X direction (horizontal direction), the size of the electro-optical device in the X direction (horizontal direction) does not increase.

  (3) In another aspect of the electro-optical device of the present invention, a feedback path for returning the image data output from the output end of the Y-direction shift register to the input end of the Y-direction shift register, and the X A selector that selectively supplies the image data supplied from the driver or the image data returned via the feedback path to the input terminal of the Y-direction shift register.

  By providing a path for connecting the input end and the output end of the Y-direction shift register, it is possible to circulate image data in the electro-optical device. For example, a screen saver has a need to circulate a specific image in the Y direction (vertical direction), and is useful as a function corresponding to such a need. In the case of a conventional electro-optical device, it is necessary for the host computer to constantly update the vertically scrolling image (newly write pixel data). In addition, since the vertical scrolling can be performed spontaneously in the electro-optical device, the host computer is not burdened.

  (4) In another aspect of the electro-optical device of the invention, the Y-direction shift register is a bidirectional shift register in which the transfer direction of the image data is switched by a transfer direction switching control signal.

  By using a bidirectional shift register (a shift register that can switch the transfer direction by a transfer direction switching control signal) as the Y-direction shift register, the image is scrolled from the bottom to the top, and the image is scrolled from the top to the bottom. Both are possible.

  (5) In another aspect of the electro-optical device of the present invention, the image data held in the latch element circuit constituting the pixel circuit of m columns and n rows (m and n are natural numbers of 1 or more). Is transferred to the latch element circuit constituting the pixel circuit in the (m + 1) -th column and the n-th row adjacent in the X direction.

  By providing an X direction (horizontal direction) shift register, it is possible to scroll image data also in the X direction (horizontal direction).

  (6) In another aspect of the electro-optical device of the present invention, the image data held in the latch element circuit constituting the pixel circuit of m columns and n rows (m and n are natural numbers of 1 or more), A data transmission path for transmitting to the latch element circuit that constitutes the pixel circuit of the (m + 1) th column and the nth row; the transfer unit circuit that constitutes the pixel circuit of the (m + 1) th column and the nth row; The m-th column and the n-th row through the image data or the data transmission path from the transfer unit circuit constituting the pixel circuit of the (m + 1) -th column and the n-th row provided between the latch element circuits. A selector for selectively supplying the image data supplied from the latch element circuit constituting the pixel circuit of the pixel circuit to the latch element circuit constituting the pixel circuit of the (m + 1) th column and the nth row. ,in front When the image data via the data transmission path is selected by the selector, the latch element circuit constituting the pixel circuit of the m-th row and the n-th column and the pixel circuit of the (m + 1) -th row and the n-th column An X-direction shift register configured to transfer the image data in the X direction, the latch element circuit configuring the m-th row and the n-th pixel circuit, The image data is transferred in the X direction by inputting transfer clocks having opposite phases to each of the latch element circuits constituting the pixel circuit of the (m + 1) th row and the nth column.

It is clarified that an X-direction shift register for shifting image data in the X direction (lateral direction) is created by connecting latch element circuits included in pixel circuits adjacent in the X direction. The X-direction (horizontal direction) shift register includes a data transmission path that connects between latch element circuits of adjacent pixels and a selector provided in each pixel, and when the horizontal transfer mode is selected by the selector. The X direction shift register becomes active, and image data can be transferred in the X direction (horizontal direction). The selector provided in each pixel transfers the image data from the Y-direction (vertical direction) shift register in parallel and the image data held in each pixel to the adjacent pixels in the X direction (horizontal). Direction transfer) mode. By appropriately connecting the latch element circuits of each pixel using a selector, an X-direction shift register can be constructed without adding new circuit elements. Then, by inputting transfer clocks having opposite phases to each of the adjacent latch element circuits, the image data is transferred one step at a time in the X direction.
Therefore, spontaneous vertical scrolling and horizontal scrolling of image data can be freely performed without increasing the size of the pixel array of the electro-optical device.

  (7) In another aspect of the electro-optical device of the invention, the electro-optical device is a reflective liquid crystal device.

  In the case of a reflective liquid crystal device, there is an empty space under the reflective electrode. Therefore, if the transistors constituting the Y-direction shift register and the latch element circuit are arranged in the empty space, the area occupied by the pixel array is particularly increased. do not do. However, the present invention is not limited to this, and the present invention can be applied to a transmissive liquid crystal device as long as a slight increase in the pixel array size is allowed.

  (8) In one aspect of the active matrix substrate of the present invention, an X driver arranged along the X direction, and image data supplied from the X driver are transferred in the Y direction orthogonal to the X direction. A Y-direction shift register configured by cascade-connecting transfer unit circuits of a plurality of stages, and held in the transfer unit circuit of each stage provided corresponding to the transfer unit circuit of each stage of the Y-direction shift register A latch circuit including a plurality of latch element circuits for latching each of the image data in parallel, a drive clock for the Y-direction shift register, and a latch circuit for latching the image data in the plurality of latch element circuits Generates a latch pulse, arranged on the X driver side, or on the opposite side of the X driver across the Y-direction shift register It has a location clock circuit.

  As a result, an active matrix substrate adopting a new image display method based on frame sequential driving, in which data of each pixel is updated by data transfer using a shift register and parallel latch to a latch element circuit, can get.

  (9) In one aspect of the active matrix substrate of the present invention, the image data held in the latch element circuit constituting the pixel circuit of m columns and n rows (m and n are natural numbers of 1 or more) are further stored. And an X-direction shift register for transferring to the latch element circuit constituting the pixel circuit in the (m + 1) -th column and the n-th row adjacent in the X-direction.

  By providing an X direction (horizontal direction) shift register, it is possible to scroll image data also in the X direction (horizontal direction).

  (10) The electronic apparatus of the present invention is equipped with the electro-optical device of the present invention.

  The electro-optical device according to the present invention does not require a Y driver and can reduce the size in the X direction (lateral direction). Therefore, by mounting the electro-optical device of the present invention, it is possible to reduce the size of electronic devices (such as portable terminals, computer terminals, and reflective projectors). In addition, since vertical schooling (including image circulation) and horizontal scrolling of images are possible, for example, one page of an electronic book is scrolled up or down or left and right by a necessary amount to form an easy-to-read display. It can be used. In addition, for example, a montage photo technique can be realized by displaying a face image and scrolling only a part of data (partial column data or row data). For example, it can be applied to a portable terminal game. Therefore, the multifunctionality, high functionality, and diversification of display functions of the electronic device are achieved, and the convenience of the electronic device is improved.

  As described above, according to the present invention, the Y driver is unnecessary in the electro-optical device, and the size of the electro-optical device in the X direction can be reduced. Further, it is possible to scroll the image data in the vertical direction and the horizontal direction in the electro-optical device. In addition, multi-functionality, high functionality, and diversification of display functions of the electronic device are achieved, and convenience of the electronic device is improved.

    Next, embodiments of the present invention will be described with reference to the drawings. Note that the present embodiment described below does not unduly limit the contents of the present invention described in the claims, and all the configurations described in the present embodiment are as means for solving the present invention. It is not always essential.

(First embodiment)
(Overall configuration of liquid crystal device)
FIG. 1 is a diagram showing an overall configuration of an example (reflection type liquid crystal device) of an electro-optical device according to the present invention. As shown in the figure, the reflective liquid crystal device (hereinafter simply referred to as a liquid crystal device) 100 is a display device having a wide screen with X: Y of 16: 9.

  The liquid crystal device 100 does not have a Y driver like the conventional device, and therefore there is no scanning line.

  Instead, in the pixel array unit 120, the liquid crystal device 100 includes a Y-direction (vertical direction) shift register 200 and a transfer unit circuit of each stage constituting the Y-direction shift register 200 (denoted as a register in the drawing). And a latch circuit 300 that latches the image data held in RY in parallel. In FIG. 1, for convenience, only one column of the Y-direction shift register 200 and one column of the latch circuit 300 are illustrated, but actually, a plurality of columns of the Y-direction shift register 200 and a plurality of columns of latch circuits 300 are provided.

  The Y-direction shift register 200 is configured by connecting a plurality of stages of transfer unit circuits (registers) RY in the Y direction. The latch circuit 300 includes a plurality of latch element circuits (unit latch circuits) RL provided corresponding to the transfer unit circuits (registers) RY at each stage. A liquid crystal element LC is connected to each latch element circuit (unit latch circuit) RL.

  A transfer unit circuit (register) RY at each stage constituting the Y-direction shift register (200) and a latch element circuit (unit latch circuit) RL arranged corresponding to the transfer unit circuit (register) RY are 1 A pixel (one pixel circuit: shown surrounded by a dotted line in the figure) G is formed. Pixels (pixel circuits) G are arranged in a matrix, thereby forming a pixel array 110.

  The liquid crystal device 100 is provided with pads P1 to Pn as external connection terminals. For example, image data and control signals are input to the pads (P1 to Pn) from a host computer.

  An X driver 110 is provided in the vicinity of the pads (P1 to Pn). The X driver 110 transfers image data (VDATA) input from the host computer via the pads (P1 to Pn) in the horizontal direction (X direction) and transfers the image data (VDATA) in the Y direction of each column. This is supplied to the shift register 200.

  A clock circuit 130 is disposed on the opposite side of the X driver 110 across the pixel array. If there is an empty space, the clock circuit 130 can be arranged on the X driver 110 side. 1 aims at reducing the size in the X direction (lateral direction), it is preferable not to employ a layout in which the clock circuit 130 is arranged along the left side or the right side of the liquid crystal device 100. (However, it is not limited to this).

  The clock circuit 130 generates two-phase transfer clocks (YCLK, / YCLK) and supplies the transfer clocks (YCLK, / YCLK) to the transfer unit circuits (registers) RY at each stage of the Y-direction shift register 200. . The clock circuit 130 generates a latch pulse (YSFT) and supplies the latch pulse (YSFT) to the latch element circuit (unit latch circuit) RL of each stage of the latch circuit 300. Note that the latch pulse (YSFT) latches the image data held in the transfer unit circuits (represented as registers in the drawing) RY of each stage constituting the Y-direction shift register 200 in parallel in the latch circuit 200. It is a clock to do.

  Although the liquid crystal device of FIG. 1 is a horizontally wide wide screen liquid crystal device, there are no Y drivers on the left and right, and thus the liquid crystal device 100 can be reduced in size.

  In the case of a reflective liquid crystal device, an empty space exists under the reflective electrode. Therefore, if the transistors constituting the Y-direction shift register 200 and the latch circuit 300 are arranged in the empty space, the pixel array 120 is occupied. The area is not particularly increased.

  Further, by arranging the clock circuit 130 on the X driver 110 side or on the opposite side of the X driver 110 with the pixel array 110 in between, the clock circuit 130 does not exist in the X direction (lateral direction), and the liquid crystal device 100. There is an advantage that the size in the X direction (lateral direction) does not increase.

(Specific internal circuit configuration of Y-direction shift register and latch circuit)
FIG. 2 is a circuit diagram showing a specific internal circuit configuration of main parts of the Y-direction shift register and the latch circuit. In FIG. 2, the same reference numerals are given to the portions common to FIG.

  In FIG. 2, RYm1 and RYm2 are transfer unit circuits (registers) in the m-th column first row and the m-th column second row, respectively, constituting the Y-direction shift register 200. RLm1 and RLm2 are latch element circuits (unit latch circuits) in the m-th column, the first row and the m-column, the second row, respectively, which constitute the latch circuit 300.

  A set of RYm1 and RLm1 constitutes a pixel (G) in the m-th column and the first row. Similarly, RYm2 and RLm1 form a set to form a pixel (G) in the m-th column and the second row.

  RYm1, RYm2, RLm1, and RLm2 all have the same configuration. Hereinafter, taking RYm1 as an example, its configuration and operation will be specifically described. Note that the configuration and operation of RYm2 are the same as those of RYm1, and a description thereof will be omitted.

  The transfer unit RYm1 in the m-th column and the first row is configured by an NMOS transistor (M1) as a transfer switch, a two-stage inverter (INV1, INV2) constituting a flip-flop, and a PMOS transistor (M2) as a switch element. Is done.

  Both the NMOS transistor (M1) and the PMOS transistor (M2) are on / off controlled by the transfer clock (YCLK). The NMOS transistor (M1) and the PMOS transistor (M2) are turned on complementarily (alternately).

  In the transfer unit circuit RYm1 in the m-th column and the first row, first, the image data is shifted by the NMOS transistor (M1) as the transfer switch (operation (1) indicated by a thick arrow), and then the shifted image data is transferred. Latched by the flip-flop (operation (2) indicated by a thick arrow).

  The CMOS configuration (configuration consisting of NMOS transistor M1 and PMOS transistor M2) is adopted as the transistor configuration constituting the Y-direction shift register 200 because the voltage level when transferring image data “1” (= VDD) is used. This is for the purpose of preventing the decrease of the above. That is, the NMOS transistor is turned on when VDD is applied to the gate. When the transfer data “1” (= VDD) is shifted in this state, the gate and the drain become the same potential (= VDD), and the gate and the drain are equivalently short-circuited, and the NMOS transistor (M1). Is saturated and functions as a MOS diode. Therefore, when the transferred image data “1” (= VDD) passes through the NMOS transistor (M1) (VDD−vth: vth is a threshold voltage of the NMOS transistor M1), it is slightly reduced. This is not preferable from the viewpoint of stabilizing the voltage of the transfer data.

  However, since the transistor constituting the flip-flop is the PMOS transistor (M2) (turned on when the gate is at the ground level), it is not saturated even when transferring the image data “1” (= VDD). It does not constitute a diode and functions as a linear resistor having a very small resistance value.

  The voltage of (VDD−vth) that has passed through the NMOS transistor (M1) is recovered to the VDD potential by the two-stage inverters (INN1, INV2) functioning as a level shifter, and the VDD potential passes through the PMOS transistor (M2). Therefore, the image data “1” can be stored by the normal voltage VDD. As a result, the voltage of the transfer data is stabilized. Therefore, even if the miniaturization and speeding-up of the element are further promoted, there is no fear of causing a malfunction in which the transfer data is erroneously inverted.

  Next, the configuration and operation of RLm1 (same for RLm2) will be described. The latch element circuit (unit latch circuit) RLm1 in the m-th column and the first row constituting the latch circuit 300 includes an NMOS transistor (M3) as a transfer switch, two-stage inverters (INV3 and INV4) constituting a flip-flop, and And a PMOS transistor (M4) as a switch element.

  Both the NMOS transistor (M3) and the PMOS transistor (M4) are controlled to be turned on / off by a latch clock (YSFT). The NMOS transistor (M3) and the PMOS transistor (M4) are turned on complementarily (alternately).

  In the latch element circuit (unit latch circuit) RLm1 in the m-th column and the first row, first, the image data is shifted by the NMOS transistor (M2) as the transfer switch (operation (3) indicated by a thick arrow), and then the shift is performed. The image data thus obtained is latched by the flip-flop (operation (4) indicated by a thick arrow). Then, the latched voltage is applied to the liquid crystal element (LC) to display an image.

(Scroll Y direction of image data)
FIG. 3 is a circuit diagram showing a circuit configuration of a main part of the liquid crystal device when image data can be scrolled in the Y direction. In FIG. 3, the same reference numerals are given to the portions common to the above-mentioned drawings.

  FIG. 3 shows the pixel circuit in the m-th column and the first row to the pixel circuit in the m-th column and the fourth row. As shown in the upper side of FIG. 3, the buffer DRm1 supplies a transfer clock (YCLKm) to the first gate line K1. Similarly, the buffer DRm2 supplies the transfer clock (/ YCLKm) to the second gate line K1. The buffer DRm3 supplies the latch clock (YSFTm) to the third gate line K3.

  3, the X driver 110 includes a shift register configured by cascade-connecting transfer unit circuits RXm for horizontal transfer in the X direction (horizontal direction). The transfer unit circuit RXm includes an NMOS transistor (M10), a PMOS transistor (M20), and two-stage inverters (INV1, INNV2). DQ1m is a buffer for inputting image data (VDATA). DQm2 is a buffer for inputting a transfer clock (/ XCLK). DQm3 is a buffer for inputting a transfer clock (XCLK).

  In FIG. 3, it should be noted that a feedback path LP is provided for returning the image data (VDATA) output from the output terminal (OUT1) of the Y-direction shift register 200 to the input terminal (IN1). In addition, a selector 105 (including switches MS1 and MS2 including NMOS transistors) for selecting image data to be input to the input terminal (IN1) of the Y-direction shift register 200 is provided.

  On / off of the switch (MS1) constituting the selector 105 is controlled by a control signal (A). On / off of the switch (MS2) is controlled by the control signal (B). When the switch (MS1) is turned on, image data (VDATA: indicated by a bold arrow in the figure) fed back from the output terminal (OUT1) of the Y-direction shift register 200 is given to the input terminal (IN1).

  On the other hand, when the switch MS2 is turned on, the image data (VDATA) from the X driver 110 is given to the input terminal (IN1).

  As described above, by making it possible to appropriately construct a path (LP) that connects the input terminal (OUT1) and the output terminal (IN1) of the Y-direction shift register 200, image data (VDATA) is generated in the liquid crystal device 100. Can be circulated spontaneously.

  For example, a screen saver has a need to circulate a specific image in the Y direction (vertical direction), and is useful as a function corresponding to such a need. In the case of the conventional liquid crystal device, it is necessary for the host computer to constantly update the vertically scrolling image (newly write pixel data). However, in the case of the liquid crystal device of FIG. Since the data can be scrolled vertically in the liquid crystal device, there is an advantage that a burden on the host computer does not occur.

(Circuit configuration using a bidirectional shift register)
FIG. 4 is a circuit diagram showing an example in which a bidirectional shift register is used as the Y-direction shift register.

  The Y-direction shift register 200 is composed of a bidirectional shift register that can switch the transfer direction of image data (VDATA). The bidirectional shift register can switch the transfer direction of image data (VDATA) by a transfer switching control signal (not shown in FIG. 4).

  That is, in the liquid crystal device shown in FIG. 4, as indicated by the thick black arrow (DK1), the image data can be returned from the output terminal (OUT1) to the input terminal (IN1), and the white thick arrow ( As indicated by DK2), the image data can be returned from the input end (IN1) to the output end (OUT1).

  This allows both scrolling the image from bottom to top and scrolling from top to bottom. Accordingly, the variety of display is increased, and an unprecedented and novel image display is possible.

  The specific circuit configuration and basic operation of the bidirectional shift register will be described in detail later.

(Horizontal scrolling of image data by X direction shift register)
In the present embodiment, a mode in which image data can be scrolled in the X direction (horizontal direction) by providing an X direction (horizontal direction) shift register will be described. That is, by connecting the latch element circuits (RL) constituting the latch circuit 300, an X-direction shift register for transferring image data in the X direction (horizontal direction) can be constructed.

  FIG. 5 is a diagram showing an outline of a configuration of a liquid crystal device capable of scrolling image data in the X direction by the X direction shift register. In FIG. 5, the same reference numerals are given to the portions common to the above-mentioned drawings.

  In FIG. 5, attention is paid to the pixel (pixel circuit) Gmn in the m-th column and the n-th row and the adjacent pixel (pixel circuit) G (m + 1) n in the (m + 1) -th column and the n-th row. As illustrated, the latch element circuit (RLmn) included in the pixel (Gmn) in the m-th column and the n-th row and the latch element circuit (RL (m + 1) n) in the (m + 1) -th column and the n-th row include image data. And a selector 205 (m + 1) is interposed in the image data transmission path (LX).

  The selector 205 (m + 1) is arranged between the transfer unit circuit (register) RY (m + 1) and the latch element circuit (RL (m + 1) n) in the pixel (G (m + 1) n) in the (m + 1) column nth row. Is provided.

  The selector 205 (m + 1) selects either the image data from the transfer unit circuit (register) RY (m + 1) or the image data shifted via the transmission path (LX), and latches it. It serves to supply the circuit (RL (m + 1) n).

  When the selector 205 (m + 1) is in a mode for passing the image data shifted via the transmission path (LX), the X-direction shift register 230 for transferring the image data in the X direction is constructed.

  A first transfer clock (not shown in FIG. 5) is supplied to the previous latch element circuit (RLmn), and a first transfer clock is supplied to the next latch element circuit (RL (m + 1) n). A second transfer clock (not shown in FIG. 5) having a phase opposite to that of is supplied. As a result, the image data is transferred from the latch element circuit (RLmn) at the previous stage to the latch element circuit (RL (m + 1) n) at the next stage.

  In the above description, the m columns of pixels and the (m + 1) columns of pixels have been described. Similarly, the latch element circuits of adjacent pixels are connected by an image data transmission path, and the selector is activated. An X-direction shift register 230 for transferring image data in the horizontal direction is constructed. Then, by inputting and driving each of the two-phase transfer clocks to each of the odd-numbered latch element circuits and the even-numbered latch element circuits, the image data can be shifted one stage at a time.

  FIG. 6 is a circuit diagram showing a specific circuit configuration of a liquid crystal device capable of scrolling image data in the X direction by the X direction shift register. In FIG. 6, the same reference numerals are given to the portions common to the above-mentioned drawings.

  On the left side of FIG. 6, m-column-type pixels (m-column first row pixel (Gm1) to m-column fourth row pixel (Gm4)) are described. Further, on the right side of FIG. 6, (m + 1) column-related pixel (m + 1) column first row pixel (G (m + 1) 1) to (m + 1) column fourth row pixel (G (m + 1) 4)) Is described.

  The selector 205 (205 (m), 205 (m + 1)) shown in FIG. 5 includes two switches (NMOS transistors) ST1 and ST2 in FIG. The on / off of the switch ST1 is driven by the control signal A, and the on / off of the switch ST2 is driven by the control signal B having a reverse phase.

  In FIG. 6, LX1 is an image data transmission path connecting RLm1 and RL (m + 1) 1, and LX2 is an image data transmission path connecting RLm2 and RL (m + 1) 2, and LX3, RLm3 and RL ( m + 1) 3 and LX4 is an image data transmission path connecting RLm4 and RL (m + 1) 4.

  Also, what should be noted in FIG. 6 is that selectors (400m, 400 (m + 1)) are provided on the upper side of FIG. These selectors (400m, 400 (m + 1) selectively supply a latch pulse (YSFT) or an X-direction transfer pulse (YCLK, / YCLK) to the latch element circuit (RL) of each column. It is provided for.

  Which pulse the selector (400m, 400 (m + 1)) selects is determined by the selection signal SLT (SLTm, SLT (m + 1)).

  When the X-direction transfer mode of image data is selected, the selector 400m in the m-th column supplies the first transfer clock (/ YCLK) for the Y-direction shift register to the latch element circuit (RLm) in each row. On the other hand, the selector 400 (m + 1) in the (m + 1) th column supplies the second transfer clock (YCLK) for the Y-direction shift register to the latch element circuit (RL (m + 1)) in each row. As a result, the image data is shifted by one step in the X direction.

  In this way, the data transfer path (LX) connecting the latch element circuits of adjacent pixels and the selectors (205, switches ST1 and ST2) provided in each pixel are configured, and the horizontal transfer mode is selected by the selector. When X is selected, the X direction shift register 230 (see FIG. 5) becomes active, and image data can be transferred in the X direction (horizontal direction).

  A selector (205, switches ST1 and ST2) provided in each pixel is configured to latch the image data (VDATA) from the Y-direction (vertical direction) shift register 200 in parallel, and the image data ( VDATA) is transferred to a pixel adjacent in the X direction (transverse transfer) mode, and by appropriately connecting the latch element circuits of each pixel using a selector, The X-direction shift register 230 can be constructed without adding new circuit elements.

  Then, by supplying transfer clocks (YCLK, / YCLK) having opposite phases to each latch element circuit, the image data (VDATA) is shifted rightward (or leftward) one by one.

  Thus, according to the present embodiment, it is possible to freely perform voluntary vertical scrolling and horizontal scrolling of image data without increasing the size of the pixel array of the liquid crystal device.

(Example of configuration and operation of bidirectional shift register)
Hereinafter, an example of the configuration and operation of the bidirectional shift register used in the embodiment of FIG. 4 will be described.

  FIG. 7 is a block diagram showing an outline of the double shift register. First, the bidirectional shift register 1 will be described. The bidirectional shift register 1 switches the transfer direction of the start pulse SP in accordance with a transfer direction control signal (transfer direction switching control signal) DIR that indicates the transfer direction. Specifically, the start pulse SP is shifted in the right direction (left to right) when the transfer direction control signal DIR is H level, and the start pulse is shifted in the left direction (right to left) when the transfer direction control signal DIR is L level. Shift SP.

  As shown in FIG. 7, the bidirectional shift register 1 includes a data transfer unit 2 and a clock control unit 3. The data transfer unit 2 in this example includes n data transfer unit circuits Ua1, Ua2,..., Uaj (j is a natural number of 2 or more and less than n), Uan, transfer gates TG1 and TG2, and an inverter INV1.

  The inverter INV1 inverts the logic level of the transfer direction control signal DIR to generate an inverted transfer direction control signal DIRB. When the transfer direction control signal DIR is at the H level, the transfer gate TG1 is turned on and the transfer gate TG2 is turned off. On the other hand, when the transfer direction control signal DIR is at the L level, the transfer gate TG1 is turned off and the transfer gate TG2 is turned on. That is, when the transfer direction control signal DIR indicates an H level shift instruction, the start pulse SP is supplied to the rightmost data transfer unit circuit Ua1, and the transfer direction control signal DIR indicates an H level shift instruction. In this case, the start pulse SP is supplied to the leftmost data transfer unit circuit Uan.

  FIG. 8 is a circuit diagram showing a configuration of a transfer unit circuit constituting the bidirectional shift register. FIG. 8 shows a circuit diagram of the j-th data transfer unit circuit Uaj. The other data transfer unit circuits are similarly configured.

  As shown in FIG. 8, the data transfer unit circuit Uaj includes clocked inverters 10 and 11, a NOR circuit 12, P-channel transistors P1 and P2, and N-channel transistors N1 and N2. When the transfer direction is the right direction, the transistors P1 and N1 constitute a write switch SWaj, and the write switch SWaj is provided between the first terminal S1 and the first connection point S3. The transistors P2 and N2 constitute a hold switch SWbj, and the hold switch SWbj is provided between the first connection point S3 and the second terminal S2. The NOR circuit 12 provided between the first connection point S3 and the second connection point S4 functions as an inverting circuit when the reset signal REST is inactive. Further, a clocked inverter 0 is provided between the second connection point S4 and the first terminal S1, and a clocked inverter 11 is provided between the second connection point S4 and the second terminal S2.

  The transistor P1 is supplied with the first clock signal CK1j, the transistor N1 is supplied with the second clock signal CK2j, the transistor N2 is supplied with the third clock signal CK3j, and the transistor P2 is supplied with the fourth clock signal CK4j. The first to fourth clock signals CK1j to CK4j are supplied from a clock control circuit Ubj provided corresponding to the data transfer unit circuit Uaj, and the input signal INj and the output signal OUTj of the data transfer unit circuit Uaj are the clock control circuit. Supplied to Ubj.

  The shift signal Qj is taken out from the NOR circuit 12. The reset signal REST is supplied to one input terminal of the NOR circuit 12, and the connection point of the write switches SWaj and SWbj is connected to the other input terminal. The reset signal REST becomes active at the H level. When the H level reset signal REST is supplied, the logical level of the shift signal Qj is forcibly set to the L level. When the power is turned on, the logic levels of the shift signals Q1 to Qn of the data transfer unit circuits Ua1 to Uan are varied. In such a case, the reset signal REST is used to align the logic levels of the output signals Q1 to Qn to the L level.

  The clocked inverter 10 operates as an inverter when the inverted transfer direction control signal DIRB is at the H level, while the output terminal is in a high impedance state when the inverted transfer direction control signal DIRB is at the L level. The clocked inverter 11 operates as an inverter when the transfer direction control signal DIR is at the H level, while the output terminal is in a high impedance state when the transfer direction control signal DIR is at the H level.

  FIGS. 9A and 9B are diagrams for explaining the two-way transfer operation. In FIG. 8, if the reset signal REST is inactive (L level) and the transfer direction control signal DIR is H level, the transfer direction is rightward, and the equivalent circuit of the data transfer unit circuits Uaj and Uaj + 1 is As shown in FIG. In this case, the clocked inverter 10 becomes inactive, and the NOR circuit 12 functions as an inverter. If the reset signal REST is inactive (L level) and the transfer direction control signal DIR is L level, the transfer direction is leftward, and the equivalent circuit of the data transfer unit circuits Uaj and Uaj + 1 is shown in FIG. As shown in (B).

  Next, the clock control unit 3 shown in FIG. 7 will be described. The clock control unit 3 includes an inverter INV2 that inverts the normal clock signal CK and outputs an inverted clock signal CKB, and a plurality of clock control circuits Ub1, Ub2,..., Ubj,. Each of the clock control circuits Ub1 to Ubn is provided corresponding to each of the plurality of data transfer unit circuits Ua1 to Uan, and includes a clock supply circuit 20 and a clock input circuit 30. The forward clock signal CK is supplied to the odd-numbered clock control circuits Ub1, Ub3, Ub5,..., While the inverted clock signal CKB is supplied to the even-numbered clock control circuits Ub2, Ub4, Ub6,. The In this example, “j” is an odd number.

  FIG. 10 is a block diagram showing a configuration of a clock control circuit constituting the bidirectional shift register. FIG. 10 shows a block diagram of the clock control circuit Ubj at the j-th stage. The clock input circuit 30 includes a first enable signal generation circuit 31, a NOR circuit 32, a transfer gate 33, a second enable signal generation circuit 34, a NAND circuit 35, and a transfer gate 36. The transfer gate 33 is turned on when the transfer direction control signal DIR is H level, that is, when the transfer direction is right direction, and when the transfer direction control signal DIR is L level, that is, when the transfer direction is left direction. Will be off. On the other hand, the transfer gate 36 is turned on when the inverted transfer direction control signal DIRB is H level, that is, when the transfer direction is leftward, and when the inverted transfer direction control signal DIRB is L level, that is, the transfer direction is changed. Turns off when in the right direction. Therefore, when the transfer direction is the right direction, the output signal of the NOR circuit 32 is supplied to the clock supply circuit 20 as the clock signal CLK, whereas when the transfer direction is the left direction, the output signal of the NAND circuit 35 is The clock signal CLK is supplied to the clock supply circuit 20. The transfer gates 33 and 36 function as a selection unit that selects the output signal of the NOR circuit 32 and the output signal of the NAND circuit 36 according to the transfer direction control signal DIR and outputs the selected signal as the clock signal CLK.

  The first enable signal EN1 that is active at the L level is supplied to one input terminal of the NOR circuit 32, and the normal clock signal CK is supplied to the other input terminal. The first enable signal EN1 is a signal that permits input of the normal rotation clock signal CK.

(Second Embodiment)
In this embodiment, an example of an electronic apparatus in which the liquid crystal device (electro-optical device) of the invention is mounted will be described.

(projector)
First, a projector using the electro-optical device of the present invention as a light valve will be described. FIG. 11 is a diagram showing an overall configuration of a projector equipped with the electro-optical device (reflection type liquid crystal device) of the present invention.

  As shown in the figure, a polarization illumination device 1110 is disposed inside the projector 1100 along the system optical axis PL. In this polarization illumination device 1110, the light emitted from the lamp 1112 becomes a substantially parallel light beam as reflected by the reflector 1114, and enters the first integrator lens 1120. Thereby, the emitted light from the lamp 1112 is divided into a plurality of intermediate light beams. The divided intermediate light beam is converted into one type of polarized light beam (s-polarized light beam) whose polarization directions are substantially uniform by a polarization conversion element 1130 having a second integrator lens on the light incident side, and the polarized illumination device It is emitted from 1110.

  The s-polarized light beam emitted from the polarization illumination device 1110 is reflected by the s-polarized light beam reflection surface 1141 of the polarization beam splitter 1140. Of this reflected light beam, the blue light (B) light beam is reflected by the blue light reflecting layer of the dichroic mirror 1151 and modulated by the reflective electro-optical device 100B. Of the light beams that have passed through the blue light reflecting layer of the dichroic mirror 1151, the red light (R) light beam is reflected by the red light reflecting layer of the dichroic mirror 1152, and is modulated by the reflective liquid electro-optical device 100R. The

  On the other hand, among the light beams transmitted through the blue light reflecting layer of the dichroic mirror 1151, the green light (G) light beam is transmitted through the red light reflecting layer of the dichroic mirror 1152 and modulated by the reflective electro-optical device 100G. .

  In this way, the red, green, and blue lights that have been color-light modulated by the electro-optical devices 100R, 100G, and 100B are sequentially combined by the dichroic mirrors 1152 and 1151, and the polarization beam splitter 1140, and then are projected by the projection optical system 1160. Is projected on the screen 1170. In addition, since the light beams corresponding to the primary colors of R, G, and B are incident on the electro-optical devices 100R, 100B, and 100G by the dichroic mirrors 1151, 1152, a color filter is not necessary.

  As described above, the electro-optical devices (100R, 100G, and 100B) of the present invention do not require a Y driver, and thus occupy a small area and contribute to downsizing of electronic devices. In addition, Y-direction scrolling and X-direction scrolling of images are possible, and various image formations that are not possible in the past are possible. At that time, it is not necessary for the host computer to write a new image, reducing the burden on the host computer. The The projector of FIG. 11 is small and has low power consumption, and can freely display images. For example, it is useful as a projector for a home theater.

  In the above-described example, a reflective electro-optical device is used. However, a projector using a transmissive display electro-optical device may be used. However, in the liquid crystal device of the present invention, since one pixel includes a plurality of storage circuits, the number of elements in the pixel portion tends to increase. Considering this point, it is easy to secure a sufficient free space (that is, The reflective liquid crystal device is advantageous in that the element can be arranged under the reflective electrode.

(Mobile computer)
Next, an example in which the electro-optical device of the present invention is applied to a mobile personal computer will be described. FIG. 12 is a perspective view showing the configuration of a personal computer equipped with the electro-optical device of the present invention.

  In FIG. 12, a computer 1200 includes a main body 1204 provided with a keyboard 1202 and a display unit 1206. The display unit 1206 is configured by adding a front light to the front surface of the electro-optical device 100 described above. In this configuration, since the electro-optical device 100 is used as a reflection direct-view type, it is desirable that the pixel electrode 118 has irregularities so that the reflected light is scattered in various directions.

  As described above, since the electro-optical device of the present invention does not require a Y driver, it occupies a small area and contributes to miniaturization of an electronic device (mobile computer). In addition, Y-direction scrolling and X-direction scrolling of images are possible, and various image formations that are not possible in the past are possible. At that time, it is not necessary for the host computer to write a new image, reducing the burden on the host computer. The

(Mobile device)
FIG. 13 is a perspective view showing a configuration of a mobile terminal (herein, a mobile phone terminal) equipped with the electro-optical device of the present invention. In the figure, a cellular phone 1300 includes the electro-optical device 100 along with a plurality of operation buttons 1302, an earpiece 1304, and a mouthpiece 1306. The electro-optical device 100 is also provided with a front light on the front surface as necessary. Also in this configuration, since the electro-optical device 100 is used as a reflection direct-view type, a configuration in which unevenness is formed in the pixel electrode 118 is desirable.

  As described above, the electro-optical device according to the present invention is capable of finer gradation expression without increasing the number of subfields by combining with the area gradation method. Therefore, the mobile terminal in FIG. 9 can display a higher-definition image than the conventional one while maintaining low power consumption.

  The present invention is not limited to other electronic devices (for example, liquid crystal televisions, viewfinder type, monitor direct view type video tape recorders, car navigation devices, pagers, electronic notebooks, calculators, word processors, workstations, videophones, POS terminals. The present invention can also be applied to a device equipped with a touch panel.

  As described above, according to the present invention, the Y driver is unnecessary in the electro-optical device, and the size of the electro-optical device in the X direction can be reduced.

  Further, it is possible to scroll the image data in the vertical direction and the horizontal direction in the electro-optical device.

  In addition, multi-functionality, high functionality, and diversification of display functions of the electronic device are achieved, and convenience of the electronic device is improved.

  Although the contents of the present invention have been described above with reference to the embodiments of the present invention, those skilled in the art can easily understand that many modifications can be made without departing from the spirit of the present invention. Let's go. Therefore, all such modifications are included in the present invention. For example, as the electro-optic material, a material whose transmittance is changed by voltage application can be widely used. In addition, all pixel circuits in which the switch element is modified by a diode instead of a transistor are included in the technical scope of the present invention.

  The present invention relates to an active matrix liquid crystal device (particularly, a reflective liquid crystal display device), an electro-optical device in general, such as an organic EL device and an inorganic EL device, an active matrix substrate, and an electronic device (for portable terminals, computer terminals, home theaters) This is useful as a projector.

The figure which shows the whole structure of an example (reflection-type liquid crystal device) of the electro-optical apparatus of this invention Circuit diagram showing specific internal circuit configuration of main parts of Y-direction shift register and latch circuit Circuit diagram showing circuit configuration of main part of liquid crystal device when image data can be scrolled in Y direction Circuit diagram showing an example using a bidirectional shift register as a Y-direction shift register The figure which shows the outline | summary of a structure of the liquid crystal device which can scroll image data also to a X direction by a X direction shift register. Circuit diagram showing a specific circuit configuration of a liquid crystal device capable of scrolling image data in the X direction by an X direction shift register. Block diagram showing the outline of the double shift register Circuit diagram showing the configuration of a transfer unit circuit constituting a bidirectional shift register FIGS. 9A and 9B are diagrams for explaining the two-way transfer operation. Block diagram showing the configuration of the clock control circuit constituting the bidirectional shift register The figure which shows the whole structure of the projector carrying the electro-optical apparatus (for example, reflection type liquid crystal device) of this invention. The perspective view which shows the structure of the personal computer carrying the electro-optical apparatus of this invention 1 is a perspective view showing a configuration of a mobile terminal equipped with an electro-optical device of the invention

Explanation of symbols

100 liquid crystal device 110 X driver, 120 pixel array, 130 clock circuit,
200 Y-direction shift register, 300 latch circuit,
230 X direction shift register, LC liquid crystal element, G pixel (pixel circuit),
RY unit transfer circuit (register), RL latch element circuit (unit latch circuit),
VDATA image data, YCLK, / YCLK two-phase transfer clock,
YSFT latch clock

Claims (10)

An X driver arranged along the X direction;
A Y-direction shift register configured by cascade-connecting a plurality of transfer unit circuits for transferring image data supplied from the X driver in the Y direction orthogonal to the X direction;
A plurality of latch element circuits that are provided corresponding to the transfer unit circuits at each stage of the Y-direction shift register and latch the image data held in the transfer unit circuits at the respective stages in parallel; A latch circuit;
Have
One pixel circuit is configured by one transfer unit circuit constituting the Y-direction shift register and the latch element circuit provided corresponding to the one transfer unit circuit. An electro-optical device. The electro-optical device according to claim 1,
The odd-numbered transfer unit circuits constituting the Y-direction shift register are driven by a first transfer clock, and the even-numbered transfer unit circuits perform a second transfer having a phase opposite to that of the first transfer clock. Driven by the clock,
A latch pulse for latching each of the image data held in the transfer unit circuit of each stage in parallel is input to the latch element circuit of each stage constituting the latch circuit,
The first and second transfer clocks and the latch pulse are generated by a clock circuit disposed on the X driver side or disposed on the opposite side of the X driver across the Y-direction shift register. The
An electro-optical device. The electro-optical device according to claim 1 or 2,
A feedback path for returning the image data output from the output end of the Y-direction shift register to the input end of the Y-direction shift register;
A selector that selectively supplies the image data supplied from the X driver or the image data returned via the feedback path to the input terminal of the Y-direction shift register;
An electro-optical device comprising: The electro-optical device according to any one of claims 1 to 3,
The electro-optical device, wherein the Y-direction shift register is a bidirectional shift register in which the transfer direction of the image data is switched by a transfer direction switching control signal. The electro-optical device according to any one of claims 1 to 4,
Further, the image data held in the latch element circuit constituting the pixel circuit of the m-th column and the n-th row (m and n are natural numbers of 1 or more) are the (m + 1) -th column n-th row adjacent in the X direction. An electro-optical device comprising: an X-direction shift register for transferring to the latch element circuit constituting the pixel circuit. The electro-optical device according to any one of claims 1 to 4,
The image data held in the latch element circuit constituting the pixel circuit of the m-th column and the n-th row (m and n are natural numbers of 1 or more) constitute the pixel circuit of the adjacent (m + 1) -th column n-th row. A data transmission path for transmitting to the latch element circuit;
The transfer unit circuit constituting the pixel circuit of the (m + 1) column n row provided between the transfer unit circuit constituting the pixel circuit of the (m + 1) column n row and the latch element circuit. The image data supplied from the latch element circuit constituting the pixel circuit in the m-th column and the n-th row via the data transmission path or the data transmission path is selectively transferred to the (m + 1) th column in the n-th row And a selector that supplies the latch element circuit that constitutes the pixel circuit of
When the image data via the data transmission path is selected by the selector, the latch element circuit constituting the pixel circuit of the m-th row and the n-th column and the pixel circuit of the (m + 1) th row and the n-th column An X-direction shift register for transferring the image data in the X direction, which is cascade-connected to the latch element circuit that constitutes
Transfer clocks having opposite phases are input to each of the latch element circuit constituting the pixel circuit of the m-th row and the n-th column and the latch element circuit constituting the pixel circuit of the (m + 1) -th row and the n-th column. The electro-optical device is characterized in that the image data is transferred in the X direction. The electro-optical device according to claim 1,
The electro-optical device is a reflective liquid crystal device. An X driver arranged along the X direction;
A Y-direction shift register configured by cascade-connecting a plurality of transfer unit circuits for transferring image data supplied from the X driver in the Y direction orthogonal to the X direction;
A plurality of latch element circuits that are provided corresponding to the transfer unit circuits at each stage of the Y-direction shift register and latch the image data held in the transfer unit circuits at the respective stages in parallel; A latch circuit;
A drive clock for the Y-direction shift register and a latch pulse for latching the image data in parallel in the plurality of latch element circuits are arranged, arranged on the X driver side, or sandwiching the Y-direction shift register A clock circuit disposed on the opposite side of the X driver;
An active matrix substrate. The active matrix substrate according to claim 8, wherein
Further, the image data held in the latch element circuit constituting the pixel circuit of the m-th column and the n-th row (m and n are natural numbers of 1 or more) are the (m + 1) -th column n-th row adjacent in the X direction. An active matrix substrate comprising an X-direction shift register for transferring to the latch element circuit constituting the pixel circuit.   An electronic apparatus on which the electro-optical device according to claim 1 is mounted.

Images