JP2005114984A - Electrooptical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrooptical device which is appropriate for controlling the light emission of primary color light by a light emitting light source and suppressing the degradation in color purity during displaying of a color image. <P>SOLUTION: The electrooptical device 1 is constituted of a display panel 10 disposed with pixel circuits in a matrix form, a data line driving circuit 11 for driving the data lines of the display panel 10, a scanning line driving circuit 12 for driving the scanning lines of the display panel 10, a primary color light emitting device 13 consisting of a plurality of primary color light emitting circuits emitting the primary color light for displaying the color image, a control circuit 15 for controlling the various components within the electrooptical device 1, and a power supply circuit 16 for supplying a power source to the respective components within the electrooptical device 1. The LED arrays corresponding to the respective colors R, G and B are respectively independently controlled by the primary color light emitting circuits 130 in the primary color light emitting device 13. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a time-division drive type color image display device including a primary color light emission light source, and in particular, controls emission of primary color light from the light emission light source to suppress a decrease in color purity when displaying a color image. The present invention relates to a suitable electro-optical device.

Conventionally, in a time-division drive type liquid crystal display device, the timing of switching the emission color of the light source corresponding to each of the primary colors for expressing a color image (for example, three primary colors of RGB (Red, Green, Blue)) is A general method is to switch the entire screen at once for each display data corresponding to each primary color.
Here, FIG. 13 is a diagram showing the switching timing of the emission color in the conventional time-division display type liquid crystal display device. As shown in FIG. 13, a time-division drive type display device normally divides a period of one frame into several subframes (SF1 to SF3 in the figure) when displaying an image of one frame. In each subframe, primary color light necessary for image generation (three primary colors of RGB in FIG. 13) is emitted, and at the same time, a display signal corresponding to the primary color light is displayed in pixel line units (in the DATA signal in the figure). (Y0 to Yn lines) is supplied to the liquid crystal display device to reproduce and display the primary color signals in a time-sharing manner. At that time, by switching the primary color light at a frequency that is not visually perceivable as flicker (this is called the subframe frequency), color mixing is performed on the retina together with the afterimage phenomenon of the human eye, and it is recognized as a color image. ing.

Further, there is a technique disclosed in Patent Document 1 as a time-division driving type liquid crystal display device. This was done in order to solve the problems in the conventional time-division driving method in which white light appears to be slightly grayish to the human eye, particularly with respect to white display, because the light emission luminance of the LED is not sufficient. Thus, for example, after each of three types of LED arrays of red, green, and blue corresponding to the three primary colors of RGB is emitted once each within a period of one frame, at least one of them is The display brightness is improved by emitting light again.
JP-A-11-52327

  However, in the above conventional technique shown in FIG. 13 and Patent Document 1, as shown in FIG. 13, after the display data for the primary color R is displayed, the light source of the primary color G is emitted and the display data for the primary color G is written. Since this is performed sequentially for each line (Y0 to Yn in FIG. 13), the primary color G light source emits light with respect to the display data for the previous primary color R before being rewritten to the primary color G display data. Has occurred and the color purity of the displayed color image is reduced (the same applies to the primary color B).

  Further, as a method of overcoming the above-described problems in FIG. 13 and Patent Document 1, for example, as shown in FIG. 14, a display data writing period “a” and a light emission period “b” are separately provided within a sub-frame period. Can be considered. As a result, the emission periods of the primary color lights for the Y0 to Yn lines in FIG. 14 do not overlap each other, and it is possible to prevent a decrease in color purity due to color mixing.

However, in the method shown in FIG. 14, in order to shorten the display data writing period a, it is necessary to increase the speed of the display device and the display signal transmission circuit, and the light emission period is also limited. It will be difficult to ensure.
Therefore, the present invention has been made paying attention to such an unsolved problem of the conventional technology, and controls the emission of primary color light from the light emitting light source to lower the color purity when displaying a color image. An object of the present invention is to provide an electro-optical device suitable for suppressing the above.

[Invention 1] In order to achieve the above object, an electro-optical device according to Invention 1 includes a pixel matrix in which pixel circuits are arranged in a matrix,
A plurality of scanning lines respectively connected to pixel circuit groups arranged along one of a row direction and a column direction of the pixel matrix;
A plurality of data lines respectively connected to pixel circuit groups arranged along the other of the row direction and the column direction of the pixel matrix;
A scanning line driving circuit connected to the plurality of scanning lines and sequentially selecting any one of the rows and columns of the pixel matrix;
A data line driving circuit that generates a control signal for controlling the pixel circuit based on display image data, and supplies the generated control signal to at least one data line of the plurality of data lines;
A primary color light emission circuit that emits primary color light corresponding to each of a plurality of primary colors for displaying a color image,
An electro-optical device that performs color expression of the color image by switching light emission of each primary color light by the primary color light emission circuit in a time-division manner within a period of one frame for displaying the color image,
A plurality of the primary color light emitting circuits are provided corresponding to each of a plurality of rows or a plurality of columns of the pixel matrix,
Further, the light emission control circuit includes a light emission control circuit for independently controlling the plurality of primary color light emission circuits.

With such a configuration, it is possible to independently control the primary color light emitting circuits provided for each of a plurality of rows or a plurality of columns of the pixel matrix by the light emission control circuit.
Accordingly, it is possible to suppress the occurrence of color mixing when displaying a color image by emitting light of each primary color for each row or column of the pixel matrix. In addition, since one primary color light emitting circuit is made to correspond to each of a plurality of rows or a plurality of columns of the pixel matrix, the number of light emitting circuits to be independently controlled can be reduced, and the configuration of the light emitting control circuit can be simplified. It becomes possible.

  Here, the primary color light emitting circuit is formed by one circuit for each of a plurality of primary colors, or all the primary colors are formed by a single circuit, or a plurality of primary colors. The color (the number of colors smaller than all the colors (hereinafter the same)) may be formed with one circuit, such as a single circuit. However, since the primary color light emitting circuits are provided corresponding to each of a plurality of rows or a plurality of columns of the pixel matrix, it is possible to emit light to pixels corresponding to all the pixel circuits in the rows or columns.

Further, the light emission control circuit can be controlled independently for each primary color light emission circuit that emits primary color light when the primary color light emission circuit is formed of one circuit for each primary color.
In addition, the light emission control circuit is configured such that when the primary color light emission circuit is formed by one circuit for all the primary colors, and when the primary color light emission circuit is formed by one circuit for a plurality of colors, the primary color Each light emitting circuit can be controlled independently and light emission for each color can be controlled independently.

In addition, the plurality of primary color light emitting circuits are a combination of all the primary color light emitting circuits in the case where the primary color light emitting circuit is formed by one circuit for each primary color. This means that there are multiple sets.
Further, when the primary color light emitting circuit is formed by one circuit for every primary color, this means that there are a plurality of primary color light emitting circuits.

Further, in the case where the primary color light emitting circuit is formed of one circuit for each of a plurality of primary colors, the combination corresponding to all the colors of the primary color light emitting circuit is set as one set, and there are a plurality of this set. Means.
[Invention 2] Furthermore, the electro-optical device according to Invention 2 is the electro-optical device according to Invention 1, wherein a plurality of the primary color light emitting circuits are provided corresponding to each row or each column of the pixel matrix. It is a feature.

That is, a plurality of primary color light emitting circuits are provided corresponding to each row or column of the pixel matrix.
Accordingly, it is possible to control the primary color light emission circuit corresponding to each row or column of the pixel matrix, and thus it is possible to perform fine light emission control for each row or column. Thus, the light emission period can be made longer and the luminance can be made higher than in the case where one primary color light emitting circuit is provided every two rows or more or every two columns or more.
[Invention 3] The electro-optical device according to Invention 3 is the electro-optical device according to Invention 1 or 2, wherein the light emission control circuit emits light of each primary color light by the plurality of primary color light emission circuits. The control is based on a signal related to the selection of the scanning line according to.

That is, the light emission control circuit can control the light emission of each primary color light by the plurality of primary color light emission circuits based on a signal related to the selection of the scanning line by the scanning line driving circuit, thereby Since the circuit configuration of the electro-optical device can be simplified, the circuit can be reduced in size and cost.
[Invention 4] Further, in the electro-optical device according to Invention 4, in the electro-optical device according to any one of Inventions 1 to 3, the data line driving circuit corresponds to a scanning line selected by the scanning line driving circuit. The control signal is sequentially supplied to the pixel circuit for each row or column of the scanning line,
The light emission control circuit controls the emission of the primary color light for each primary color light emission circuit corresponding to each scanning line to the pixel circuit corresponding to the selected scanning line after the selection of the scanning line. Control is performed immediately after the signal is supplied and in the period immediately before the next scanning signal is selected and the next control signal is supplied to the pixel circuit corresponding to the scanning line. .

  That is, the data line driving circuit sequentially supplies the control signal to the pixel circuit corresponding to the scanning line selected by the scanning line driving circuit for each row or column of the scanning line. The light emission control circuit controls, for each primary color light emission circuit corresponding to each scanning line, emission of the primary color light to the pixel circuit corresponding to the selected scanning line after the selection of the scanning line. It is possible to perform control after a signal is supplied and in a period before the next scanning signal is selected and the next control signal is supplied to the pixel circuit corresponding to the scanning line. .

Accordingly, when a color image is displayed, the light emission period can be lengthened while suppressing the occurrence of color mixing, so that high luminance can be obtained.
[Invention 5] The electro-optical device according to Invention 5 is the electro-optical device according to any one of Inventions 1 to 4, in which the light emission control circuit sets the period of one frame for displaying the color image to the number of primary colors. A light emission period corresponding to each numerical value when the number of gradations of the color image is expressed as a sum of 2 ^x values (x is an integer) within each subframe period divided into a plurality of subframe periods. Only the primary color light of the same color is emitted from the primary color light emission circuit to express the gradation of the color image.

That is, the light emission control circuit sets the number of gradations of the color image within a period of each subframe obtained by dividing a period of one frame for displaying the color image into a plurality of subframe periods corresponding to the number of primary colors. 2. Represent the gradation of the color image by causing the primary color light emission circuit to emit the primary color light of the same color only during the light emission period corresponding to each numerical value when represented by the sum of 2 ^x values (x is an integer). Is possible.

Accordingly, full-color display output can be performed in an electro-optical device that can display only binary values of ON / OFF for each primary color light.
Here, expressing the number of gradations as the sum of 2 ^x values (x is an integer) means that, for example, when the gradation is 10, gradation 10 is expressed as 2 ¹ +2 ³ = 2 + 8 = 10. It is expressed by two numerical values of 2 ¹ and 2 ³ . Then, the primary color light emission circuit of the same color is caused to emit light only during the light emission periods corresponding to 2 ¹ and 2 ³ within the subframe period, thereby making it possible to express the gradation of the emitted color using the properties of the human eye. I do.
[Invention 6] The electro-optical device according to Invention 6 is the electro-optical device according to any one of Inventions 1 to 5, characterized in that the primary color light emitting circuit includes an electroluminescence element.

That is, by configuring the primary color light emitting circuit with the electroluminescence element, it is possible to reduce the power consumption of the primary color light emitting circuit and to reduce the thickness of the electro-optical device.
Here, the electroluminescence element has a property that the element itself emits light when a voltage is applied, and it is not necessary to shine light from behind like a liquid crystal display. Power consumption can be reduced. Another feature is that you can see beautiful images from any angle.
[Invention 7] The electro-optical device according to Invention 7 is the electro-optical device according to any one of Inventions 1 to 6, in which the scanning line driving circuit, the data line driving circuit, the plurality of primary color light emitting circuits, The light emission control circuit is provided in the same substrate.

That is, since the scanning line driving circuit, the data line driving circuit, the plurality of primary color light emitting circuits, and the light emission control circuit are provided on the same substrate, signal lines can be easily shared. Is possible.
[Invention 8] A liquid crystal display device according to Invention 8 includes the electro-optical device according to any one of Inventions 1 to 7.

In other words, since the electro-optical device according to any one of the inventions 1 to 7 is provided, a liquid crystal display device that can suppress the occurrence of color mixing by controlling the light emission of the primary color light emitting circuit when displaying a color image. Realization is possible.
[Invention 9] An electronic device according to Invention 9 includes the liquid crystal display device according to Invention 8.

  In other words, since the liquid crystal display device according to the eighth aspect is provided, it is possible to realize an electronic device including a liquid crystal display device that can control light emission of the primary color light emission circuit and suppress the occurrence of color mixing when displaying color images. It is.

Embodiments of the present invention will be described below with reference to the drawings. 1 to 14 are diagrams illustrating an embodiment of an electro-optical device according to the invention and an electronic apparatus using the electro-optical device.
First, the configuration of the electro-optical device according to the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of an electro-optical device according to the present invention.
As shown in FIG. 1, the electro-optical device 1 includes a display panel 10 in which pixel circuits that can open and close a liquid crystal shutter in units of pixels are arranged in a matrix, and a data line driving circuit that drives data lines of the display panel 10. 11, a scanning line driving circuit 12 that drives scanning lines of the display panel 10, a primary color light emitting device 13 that includes a plurality of primary color light emitting circuits that emit primary color light for displaying a color image, and a computer 2. A memory 14 for storing display data, a control circuit 15 for controlling each component in the electro-optical device 1, and a power supply circuit 16 for supplying power to each component in the electro-optical device 1 are included. It has a configuration.

Here, in this embodiment, the data line driving circuit 11, the scanning line driving circuit 12, the primary color light emitting device 13, the memory 14, and the control circuit 15 are formed on the same substrate. To do.
Further, the configuration of the light emitting elements in the primary color light emitting device 13 will be described with reference to FIG. FIG. 2 is a diagram illustrating a configuration example of a light emitting element in the primary color light emitting device 13.

  As shown in FIG. 2, the light emitting element of the primary color light emitting device 13 is a set of three LED arrays each corresponding to the three primary colors R (Red), G (Green), and B (Blue). This LED array is arranged for each row of pixels formed in a matrix on the liquid crystal surface. In other words, if the set of LED arrays is represented as [Ri, Gi, Bi] (i = 1, 2,..., N (n is an integer)), the first line of pixels on the liquid crystal surface [R1, G1, B1], [R2, G2, B2] for the second line, and [Rn, Gn, Bn] for the nth line, respectively. Will be.

In the present embodiment, the primary color light emitting device 13 can independently control one LED array corresponding to each of the three primary colors R, G, and B for each primary color.
Further, based on FIGS. 3 to 5, the connection configuration of the above-described components of the electro-optical device 1, the internal configuration of the pixel circuit 100 that configures the display panel, and the interior of the primary color light-emitting circuit 130 that configures the light-emitting device 13. The configuration will be described. 3 is a diagram showing a connection configuration of each component constituting the electro-optical device 1, FIG. 4 is a diagram showing an internal configuration of the pixel circuit 100, and FIG. 5 is an internal configuration of the primary color light emitting circuit 130. FIG.

As shown in FIG. 3, the display panel 10 has a configuration in which a plurality of pixel circuits 100 are arranged in a matrix.
Here, as shown in FIG. 4, the pixel circuit 100 includes a pixel transistor 100a, a pixel capacitor 100b that holds a voltage corresponding to a current value input to the source of the pixel transistor 100a, and a pixel capacitor 100b. And a pixel electrode 100c that applies the applied voltage to the liquid crystal shutter.

Then, as shown in FIG. 3, the data lines X _i (i = 0, 1, 2) provided corresponding to the respective columns of the pixel circuits 100 arranged in the matrix of the data line driving circuit 11. ,..., N) are connected to the sources of the pixel transistors 100a in the pixel circuits 100 in each column via switching transistors ST _i (i = 0, 1, 2,..., N), respectively. .

Further, as shown in FIG. 3, the scanning lines Y _i (i = 0, 1, 2, and 2) provided corresponding to the respective rows of the pixel circuits 100 arranged in the matrix form of the scanning line driving circuit 12. .., N) are connected to the gates of the pixel transistors 100a in the pixel circuits 100 in each row.
For example, when the scanning line Y ₀ is selected, a current flows to the gate of the pixel transistor 100a of the pixel circuit 100 corresponding to the row of the scanning line Y ₀ , and the pixel transistor 100a is turned on. Then, the data line driving circuit 11, for example, when the data lines X ₀ is selected, the display data signal (Data in Figure 3), via the switching transistor ST _0, the selected scan lines Y ₀ It is input to and columns of data lines X ₀ in line to the source of the pixel transistor 100a in the pixel circuits 100 corresponding. As a result, a voltage corresponding to the current value of the display data signal is held in the pixel capacitor 100b connected to the drain of the pixel transistor 100a. Then, when a voltage is held in the pixel capacitor 100b, the pixel electrode applies the held voltage to the liquid crystal shutter, and the corresponding pixel portion of the liquid crystal shutter is opened. In this state, when the light emitting element emits light by the primary color light emitting circuit, the corresponding pixel is displayed in the light emitting color.

Further, as shown in FIG. 3, the primary color light emitting device 13 in the electro-optical device 1 includes the same number of primary color light emitting circuits 130_i (i = 0, 1, 2,..., N) as the number of rows of the pixel matrix. , Each row is arranged correspondingly.
Here, as shown in FIG. 5, the primary color light emission circuit 130_i includes an R_LED array 131 for emitting the primary color R, a G_LED array 132 for emitting the primary color G, and a B_LED array 133 for emitting the primary color B. A drive transistor 131a of the R_LED array 131, a drive transistor 132a of the G_LED array 132, a drive transistor 131c of the B_LED array 133, and a set-reset type flip-flop for controlling the light emission period of the R_LED array 131 , SRFF) circuit 134, SR_F circuit 135 for controlling the light emission period of G_LED array 132, SRFF circuit 136 for controlling the light emission period of B_LED array 133, and R_LED array based on color selection signal CS 131, G A logical product of RGB-SW (switch) 137 for switching which LED array of the LED array 132 and B_LED array 133 emit light, and the output of SRFF circuit 134 and the output of RGB-SF 137 is obtained. AND gate 135a for obtaining the logical product of the output of SRFF circuit 135 and the output of RGB-SF 137, and for obtaining the logical product of the output of SRFF circuit 136 and the output of RGB-SF 137 And an AND gate 136a.

  Further, driving transistors 131a, 132a, and 133a are connected to the R_LED array 131, the G_LED array 132, and the B_LED array 133 through these sources, respectively, and each output unit of the SRFF circuits 134 to 136 is connected. Are connected to the input parts of AND gates 134a, 135a and 136a, respectively. Further, the output sections of the AND gates 134a, 135a, and 136a are connected to the gates of the driving transistors 131a, 132a, and 133a, respectively.

Then, as shown in FIG. 3, the scanning lines Y _i are respectively connected to the reset NAND gates of the SRFF circuits 134 to 136 in the primary color light emitting circuit 130_i, and the set NAND gates of the SRFF circuits 134 to 136 in the same 130_i are connected. Each of the scanning lines Y _{i + 1} is connected.
Further, the scanning lines Y _i are respectively connected to reset NAND gates of the SRFF circuits 134 to 136 in the primary color light emitting circuit 130_ (i + 1), and are respectively connected to the NAND gates for setting the SRFF circuits 134 to 136 in the same 130_ (i + 1). The scanning line Y _{i + 2} is connected.

Still further, the scanning line Y ₀ is connected to the NAND gates for setting the SRFF circuits 134 to 136 in the primary color light emitting circuit 130 — _n (corresponding to the scanning line Y _n ).
That is, the primary color light emitting circuit 130_i starts the operation when the scanning line Y _{i + 1} in the next row is selected, and causes the LED array of the color selected by the RGB-SW 137 to emit light. This light emission state is held by the SRFF circuits 134 to 136 until the scanning line Y _i is next selected.

For example, when the period of one frame is divided into three equal periods of the subframes SF1 to SF3, when the R_LED array 131 of the primary color light emitting circuit 130_i corresponding to the scanning line Y _i emits light during the period of SF1, The light emission is continued until Y _i is selected again in the subframe SF2 in order to display the display data corresponding to the primary color G. Similarly, the light emission of the G_LED array 132 is continued until Y _i is selected again in the subframe SF3 in order to display the display data corresponding to the primary color B.

Further, the configuration and operation of the scanning line driving circuit 12 will be described with reference to FIGS. FIG. 6 is a diagram illustrating an internal configuration of the scanning line driving circuit 12, and FIG. 7 is a diagram illustrating a timing chart during the operation of the scanning line driving circuit 12.
As shown in FIG. 6, the scanning line driving circuit 12 includes a first inverter that inverts a positive logic input and outputs a negative logic output, and inverts the negative logic input to a positive logic input. And a second inverter that outputs and an AND gate i (i = 0, 1, 2,..., N). Then, two first inverters and one second inverter are combined to form a shift register i (i = 0, 1, 2,..., N), and this shift register i is connected in series to n + 1. Further, the output part of the shift register (i + 1) and the output part of the shift register (i + 2) are connected to the input part of the AND gate, respectively.

That is, in the scanning line selection circuit 12, the control signal DY input to the shift register 0 is sequentially shifted by the clock signal CLY supplied to each shift register i and CLYB obtained by inverting the clock signal CLY. Since the output (i + 1) is input to the AND gate i, the logical product of these is output as a scanning line selection signal.
Further, a specific operation of the scanning line driving circuit 12 will be described with reference to FIG. The timing chart of FIG. 7 shows the control signal DY, the clock CLY, the output Mi (i = 0, 1, 2,..., N) of the shift register i, and the output Qi (i) of the shift register (i + 1). = 0, 1, 2,..., N) and a scanning line selection signal Yi (i = 0, 1, 2,..., N). Here, the control signal DY and the clock CLY described above are supplied by the data control circuit 15.

  As shown in the timing chart of FIG. 7, when the control signal DY is first input to the shift register 0, the control signal DY is used as the output Mi of each shift register i and the output Qi of the shift register (i + 1). What is shifted by one clock with respect to the output of the register is output alternately and sequentially. When Q0 is output from the shift register 1, the AND gate 0 outputs a logical product of this Q0 and M0 output from the previous shift register 0 as the scanning line selection signal Y0. Thus, the scanning line selection signal Yi is obtained by inputting the output Qi of each shift register i and the output Mi of the shift register (i + 1) to the AND gate i while sequentially shifting them.

Here, since the data line driving circuit 11 has the same configuration as the scanning line driving circuit 12, detailed description thereof is omitted.
Further, based on FIG. 8, a specific operation of the light emission control of the LED array in the primary color light emitting device 13 will be described. FIG. 8 is a timing chart showing the operation of each circuit during light emission control of the primary color light emitting device 13. In FIG. 8, the control signal DY in the scanning line driving circuit 12, the clock CLY, the data signal DATA in the data line driving circuit 11, and the light emission period Ryi (i = 0) in the primary color light emitting circuit 130i. , 1, 2,..., N), the light emission period Gyi (i = 0, 1, 2,..., N) of the G_LED array 132, and the light emission period Byi (i = 0, 1) of the B_LED array 133. , 2,..., N).

  Here, in the present embodiment, the image data transmitted from the computer 2 is stored in the memory 14, and display processing for one image of the stored image data is performed in a period of one frame. Further, this one-frame period is divided into three equal periods of subframes SF1 to SF3. In subframe SF1, display data display processing corresponding to the primary color R is performed, and in subframe SF2, the primary color G is displayed. Corresponding display data display processing is performed, and display data display processing corresponding to the primary color B is performed in the subframe SF3.

As shown in FIG. 8, the data line driving circuit 11, in response to the falling edge of the control signal DY, every half cycle of the clock CLY, from the scanning line Y ₀ to the scan line Y _n, in turn, corresponds to the primary colors R The data signal of the displayed data is input to the pixel circuit 100 corresponding to the scanning line Y _i selected by the scanning line selection circuit 12 via the data signal line X _i .
Accordingly, a voltage corresponding to the current value of the data signal input to the source of the pixel transistor 100a of the pixel circuit 100 is held in the pixel capacitor 100b (hereinafter, this is expressed as writing display data to the pixel circuit 100). .

Further, the pixel electrode 100c of the pixel circuit 100 applies the voltage held in the pixel capacitor 100b to the corresponding pixel portion of the liquid crystal shutter. Here, the writing of display data is performed for all the pixel circuits 100 corresponding to the rows of the scanning lines Y _i.
When the display data corresponding to the primary colors R to all the pixel circuits 100 corresponding to the row scanning line Y _i is written in synchronization with the rising of the not shown scanning line selection signal Yi, R_LED arrays in primary light emitting circuit 130_i A light emission process 131 is performed. At this time, the RGB-SW 137 receives a color selection signal CS for selecting red from the data control circuit 15. As a result, both the output of the SRFF circuit 131 and the color selection signal CS, which are the two inputs of the AND gate 134a of the primary color light emitting circuit 130_i, are at a high level, a current flows to the gate of the driving transistor 131a of the R_LED array 131, and the R_LED The array 131 emits light.

  That is, the light emission processing of the R_LED array 131 of the primary color light emission circuit 130_0 performed in synchronization with the rising edge of the scanning line selection signal Y1 starts, and then the R_LED of the primary color light emission circuit 130_1 in synchronization with the rising edge of the scanning line selection signal Y2. The light emission processing of the array 131 is performed, and further, the light emission processing of the R_LED array 131 of the primary color light emission circuit 130_2 is performed in synchronization with the rise of the scan line selection signal Y3, so that it is synchronized with the rise of the scan line selection signal Y0. The light emission processing described above is sequentially performed until the light emission processing of the R_LED array 131 of the primary color light emission circuit 130_n is performed.

In this way, when the display processing of the display data corresponding to the primary color R is completed in the period of the sub-frame SF1, the process proceeds to the display processing of display data corresponding to the primary color G in the sub-frame SF2, and the primary color G When the display data display process corresponding to is finished, the process further shifts to the display data display process corresponding to the primary color B in the subframe SF3.
Here, light emission of R_LED array 131 of primary light emitting circuit 130_i, in subframe SF2, the scanning line _{Y i} is continued until the selected. That is, as shown in FIG. 8, the period until emission of R_LED array 131 of primary light emitting circuit 130_0 corresponding to the scanning line Y ₀ in the sub-frame SF1 is the scanning line Y ₀ in the sub-frame SF2 is selected, i.e. FIG. The middle light emission period Ry0 is performed only during a high level period. Similarly, emission of R_LED array 131 of primary light emitting circuit 130_1 corresponding to the scanning line Y _1, the light emitting period Ry1 is performed only during the period of high level, the primary light emitting circuit 130_n corresponding to the scanning line _{Y n} of R_LED array 131 Light emission is performed only during a period in which the light emission period Ryn is at a high level.

The light emitting period as described above, are the same for the light emission of the light emitting and primary light emitting circuit 130_I of B_LED array 133 of G_LED array 132 of primary light emitting circuit 130_I, as shown in FIG. 8, the scanning lines Y ₀ in the sub-frame SF2 emission of G_LED array 132 of the corresponding primary light emitting circuit 130_0, the light emission period Gy0 is performed only during the period of high level, the emission of G_LED array 132 of primary light emitting circuit 130_1 corresponding to the scanning line Y _1, the light emitting period Gy1 is high done only during the period of the level, emission of G_LED array 132 of primary light emitting circuit 130_n corresponding to the scanning line _{Y n,} the light emitting period Gyn is performed only while the high level. Furthermore, emission of B_LED array 133 of primary light emitting circuit 130_0 corresponding to the scanning line Y ₀ in the sub-frame SF3, the light emitting period By0 is performed only during the period of high level, B_LED of primary light emitting circuit 130_1 corresponding to the scanning line Y ₁ emission array 133, the light emitting period By1 is performed only during the period of high level, emission of primary light emitting circuit 130_n of B_LED array 133 corresponding to the scanning line _{Y n,} the light emitting period Gyn is performed only while the high level.

Thus, in the period of the subframe SF1~ subframe SF3, 3 with respect to the primary colors of RGB, respectively writes the display data corresponding to the primary colors in the pixel circuits of the scan line Y _i, emitting an LED array of primary light emitting circuit To display a color image.
As described above, in the present embodiment, the light-emitting elements in the primary color light-emitting device 13 are each configured by arranging a set of three RGB LED arrays for each row of pixels formed in a matrix on the liquid crystal surface. Further, by controlling the primary color light emitting circuit 130_i corresponding to each of these LED arrays, the light emission processing of the R_LED array 131, the G_LED array 132, and the B_LED array 133, which is a set of the above three RGB LED arrays, is scanned. Each line Y _i can be controlled independently.

Further, primary light emitting circuit 130_i is, R_LED array 131, corresponding to the respective G_LED arrays 132 and B_LED array 133 includes a SRFF circuit 134-136, these SRFF circuits, in the sub-frame SF1, R_LED array for scanning line _{Y i} It is possible to continue the light emission of 131 until the scanning line Y _i is selected in the subframe SF2, and similarly, the light emission of the G_LED array 132 for the scanning line Y _i in the subframe SF2 is performed in the subframe SF3. , Until the scanning line Y _i is selected, the light emission of the B_LED array 131 with respect to the scanning line Y _i in the sub-frame SF3 can be continued in the sub-frame SF1 for the next image to be displayed continuously. , the scanning line _{Y i} is It is possible to continue until it is-option.

In the above embodiment, the display image can be expressed in eight colors by sequentially emitting the LED arrays corresponding to the three primary colors of RGB as the light emitting elements during the period of each subframe. However, according to the gradation of each color of the color image, the number of gradations is expressed as a sum of 2 ^x , and in each subframe period corresponding to the number of primary colors, only the period corresponding to each of these 2 ^x values By emitting light from each color light emitting element, it is possible to express eight or more color images.

That is, as shown in FIG. 9, when the number of red gradations of the color image is 10, this is first expressed as a sum of 2 ^× . As shown in FIG. 9, the gradation 10 can be expressed by the sum of 2 ¹ and 2 ³ . Here, the light emission periods corresponding to the numerical values of 2 ^{0 to} 2 ³ are periods indicated by 110a to 110d shown in FIG. Therefore, as indicated by 111 in FIG. 9, the red light of gradation 10 is expressed by performing the light emission of the R_LED array 131 during the period 110a and the light emission of the R_LED 131 during the period 110d within the period of the subframe 1F. can do. Similarly, when the gradation 6 is green, the G_LED 132 during the period 110b and the G_LED 132 during the period 110c are emitted during the period of the subframe 2F. is there.

  In the above embodiment, as shown in FIG. 2, the configuration of the light emitting elements in the primary color light emitting device 13 is a combination of three RGB RGB LED arrays arranged in a matrix with respect to the liquid crystal surface. Although it is configured so as to be arranged for each row, the present invention is not limited to this. As shown in FIG. 10, a set of three LED arrays of RGB includes a plurality of pixels formed in a matrix on the liquid crystal surface. It is good also as a structure each arrange | positioned for every line (every 3 lines in FIG. 10). In this way, the number of primary color light emitting circuits 130_i can be reduced, and the circuit can be reduced in size and cost. However, in order to avoid color mixing, it is necessary to emit light after all display data has been written to the pixel circuits of a plurality of lines corresponding to the light emitting elements. Therefore, if the number of primary color light emitting circuits 13 is excessively reduced, luminance decreases. There is a risk of becoming serious.

The electro-optical device 1 described above can be applied to various electronic devices such as a mobile personal computer and a mobile phone.
FIG. 11 is a perspective view illustrating a configuration of a mobile personal computer. The personal computer 1000 includes a main body 1040 including a keyboard 1020 and a display unit 1060 using the electro-optical device 1 described above.

FIG. 12 is a perspective view of a mobile phone. The cellular phone 2000 includes a plurality of operation buttons 2020, a mouthpiece 2040, a mouthpiece 2060, and a liquid crystal display panel 2080 using the electro-optical device 1 described above.
In addition to the personal computer 1000 shown in FIG. 11 and the mobile phone 2000 shown in FIG. 12, electronic devices include digital cameras, televisions, viewfinder type and monitor direct view type video tape recorders, car navigation devices, pagers, and electronic devices. Examples include a notebook, a calculator, a word processor, a workstation, a video phone, a POS (Point Of Sale) terminal, and a device equipped with a touch panel. A display unit using the electro-optical device 1 is applicable as a display unit of these various electronic devices.

Here, in the above embodiment, the portion composed of the scanning line selection signal Yi, the SRFF circuits 134 to 136, the AND gates 134a to 136a, and the RGB-SW 137 in the primary color light emitting circuit 130_i is the invention 1, 3, 4, Corresponding to the light emission control circuit of any one of 5 and 7, the light emission periods Ryi, Gyi, and Byi correspond to the light emission periods of each primary color light in the invention 4, and the periods 110a to 110d are 2 ^{× in} the invention 5. This corresponds to the light emission period corresponding to each of the numerical values.

In the above embodiment, the case where the three primary colors of RGB are used as the light emitting element has been described as an example. However, the present invention is not limited to this, and other colors such as C (cyan) and M (magenta) are added in addition to RGB. Then, the primary colors may be multi-colored such as four colors or five colors for color expression. Thereby, it is possible to obtain the effect of expanding the color gamut of the display image.
Moreover, in the said embodiment, although the example which used LED as a light emitting element was demonstrated, it is not restricted to this, You may use other elements, such as an electroluminescent element, as a light emitting element.

  In the above embodiment, image display processing is performed by control by hardware. However, the present invention is not limited to this, and part or all of the hardware control described above is performed by execution of a program by a processor. You may do it.

1 is a block diagram illustrating a configuration of an electro-optical device according to the invention. 3 is a diagram illustrating a configuration example of a light emitting element in a primary color light emitting device 13. FIG. FIG. 2 is a diagram showing a connection configuration of each component constituting the electro-optical device 1; 2 is a diagram illustrating an internal configuration of a pixel circuit 100. FIG. 3 is a diagram showing an internal configuration of a primary color light emitting circuit 130. FIG. 2 is a diagram showing an internal configuration of a scanning line driving circuit 12. FIG. FIG. 6 is a diagram illustrating a timing chart when the scanning line driving circuit 12 operates. 4 is a timing chart showing the operation of each circuit during light emission control of the primary color light emitting device 13. It is a figure which shows an example of the principle of the gradation display by three primary colors of RGB. It is a figure which shows the structural example which has each arrange | positioned the light emitting element for every several rows of the pixel formed in the matrix form with respect to the liquid crystal surface. It is a perspective view which shows the structure of a mobile type personal computer. It is a perspective view of a mobile phone. It is a figure which shows the switching timing of the luminescent color in the liquid crystal display device of the conventional time division display system. FIG. 11 is a diagram illustrating an example in which a display data writing period a and a light emission period b are separately provided in a subframe period in a conventional time-division display type liquid crystal display device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electro-optical device, 2 ... Computer, 10 ... Display panel, 11 ... Data line control circuit, 12 ... Scanning line control circuit, 14 ... Memory, 15 ... Data control circuit, 16 ... Power supply circuit, 100 ... Pixel circuit, 100a ... pixel transistor, 100b ... pixel capacitor, 100c ... pixel electrode, 130 ... primary color light emitting circuit, 131 to 133 ... LED array, 134 to 136 ... SRFF circuit, 137 ... RGB-SW, 1000 ... personal computer, 2000 ... mobile phone, X _i (i = 0, 1, 2,..., N)... Data line, Y _i (i = 0, 1, 2,..., N)... Scanning line, ST _i (i = 0, 1) , 2, ..., n) ... Switching transistors

Claims (9)

A pixel matrix in which pixel circuits are arranged in a matrix, and
A plurality of scanning lines respectively connected to pixel circuit groups arranged along one of a row direction and a column direction of the pixel matrix;
A plurality of data lines respectively connected to pixel circuit groups arranged along the other of the row direction and the column direction of the pixel matrix;
A scanning line driving circuit connected to the plurality of scanning lines and sequentially selecting any one of the rows and columns of the pixel matrix;
A data line driving circuit that generates a control signal for controlling the pixel circuit based on display image data, and supplies the generated control signal to at least one data line of the plurality of data lines;
A primary color light emission circuit that emits primary color light corresponding to each of a plurality of primary colors for displaying a color image,
An electro-optical device that performs color expression of the color image by switching light emission of each primary color light by the primary color light emission circuit in a time-division manner within a period of one frame for displaying the color image,
A plurality of the primary color light emitting circuits are provided corresponding to each of a plurality of rows or a plurality of columns of the pixel matrix,
The electro-optical device further includes a light emission control circuit for independently controlling the plurality of primary color light emission circuits.   2. The electro-optical device according to claim 1, wherein the plurality of primary color light emitting circuits are provided corresponding to each row or column of the pixel matrix.   3. The light emission control circuit controls light emission of each primary color light by the plurality of primary color light emission circuits based on a signal related to selection of a scanning line by the scanning line driving circuit. Electro-optic device. The data line driving circuit sequentially supplies the control signal for each row or column of the scanning line to the pixel circuit corresponding to the scanning line selected by the scanning line driving circuit,
The light emission control circuit controls the emission of the primary color light for each primary color light emission circuit corresponding to each scanning line to the pixel circuit corresponding to the selected scanning line after the selection of the scanning line. Control is performed immediately after the signal is supplied and in the period immediately before the next scanning signal is selected and the next control signal is supplied to the pixel circuit corresponding to the scanning line. The electro-optical device according to any one of claims 1 to 3. The light emission control circuit sets the number of gradations of the color image to 2 ^× within a period of each subframe obtained by dividing a period of one frame for displaying the color image into a plurality of subframe periods corresponding to the number of primary colors. Expressing the gradation of the color image by causing the primary color light emission circuit to emit the primary color light of the same color only during the light emission period corresponding to each numerical value when expressed by the sum of values (x is an integer). The electro-optical device according to claim 1, wherein:   The electro-optical device according to claim 1, wherein the primary color light emitting circuit includes an electroluminescence element.   7. The scanning line driving circuit, the data line driving circuit, the plurality of primary color light emitting circuits, and the light emission control circuit are provided on the same substrate. 2. The electro-optical device according to item 1.   A liquid crystal display device comprising the electro-optical device according to claim 1.   An electronic apparatus comprising the liquid crystal display device according to claim 8.

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