JP2006133782A - Driving circuit having a plurality of output voltages, driving circuit for display apparatus and method for driving display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To individually adjust chromatic transparency features of a color display without using a special timing controller or a multiple sets of reference voltage sources. <P>SOLUTION: The driving circuit having a plurality of output voltages comprises: a voltage generator to generate a plurality of reference voltages; and a plurality of digital/analog converters to receive a plurality of digital signals to generate a plurality of analog signals according to the reference voltages and digital signals. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a driving circuit and a driving method, and more particularly, to a driving circuit and a driving method configured to independently adjust and compensate for the gray level according to the characteristics of an image to be displayed.

  In order to independently adjust the transmission characteristics of red, green and blue, the color display device currently calculates and compensates for the image signal input by the system and provides various control voltages for adjusting and compensating for chromatic aberration. In order to generate the corresponding digital image signal to the driver, a special timing controller is required.

  FIG. 1 is a schematic block diagram showing a conventional color display driver. The driver 100 includes a shift register 110 and a data latch 120. The shift register is configured to receive a timing pulse signal supplied by an external timing controller and to be triggered by a trigger signal. The shift register controls a digital image signal corresponding to the digital image data, and sequentially delivers the digital image signal to each address channel of the data latch 120. The digital image data of the data latch 120 is supplied to a plurality of digital / analog converters 130. An external voltage source supplies reference voltages V 1 to Vn to the digital / analog converter 130 of each channel of the driver 100, and the digital / analog converter 130 provides the digital voltage provided by these reference voltage and data latch 120. A plurality of analog signals to be output to the color display panel 150 are converted in accordance with the image signal. The color display panel 150 is, for example, an LCD display.

  By the way, in the normal driver 100, the gray scale reference voltages used by the digital / analog converters of the respective channels are the same. Therefore, when the same digital data is used, the analog signals generated in each channel are the same. In a normal display device such as an LCD display, when controlled by substantially the same voltage, the resulting red, green and blue shades are not completely identical to each other, that is, a phenomenon known as chromatic aberration occurs. Affects the display quality. FIG. 2 is a conventional 2-bit digital / analog converter of the conventional driver according to FIG. Referring to FIG. 2, externally supplied reference voltages V 1, V 2, V 3 and V 4 are supplied for use by a plurality of digital / analog converters 130. When the same digital image signals D0 and D1 are input, the respective digital / analog converters 130 output the same analog signal V_out as shown in FIG. As a result, the conventional display device cannot adjust the color characteristics of red, green and blue according to individual colors.

  Methods for compensating for chromatic aberration have been conventionally provided. By calculating and compensating the input image signal to the system, a corresponding digital image signal can be provided to the driver to produce an output voltage with different color compensation, and the red, green and blue transmission characteristics are It can be adjusted independently according to individual colors. Other methods for solving the chromatic aberration problem have been provided in the past, and higher resolution drivers are used in the system. Unfortunately, both of these two methods are not only relatively complex, but also relatively inefficient and expensive.

  The present invention provides a driving circuit in which output voltages are individually controlled, and a driving method thereof. Instead of specially processing the image signal, the driver provided by the present invention can individually adjust the transmission characteristics of each color of the color display device. The object of individually adjusting the transmission characteristics of each color of the color display device can be achieved without the need for the special timing controller and a plurality of sets of reference voltage supply sources. Therefore, a complicated system can be simplified and manufacturing cost can be reduced.

  According to the driving device circuit having a plurality of output voltages provided by the present invention and the driving method thereof, depending on the color characteristics of the liquid crystal or the characteristics of the filter under the situation of using the same digital code, The driver's control voltage can be adjusted individually and the intensity can be further adjusted. Better color performance can be achieved after compensation has been performed. Therefore, the display quality is improved and the cost is reduced.

  In one embodiment, the present invention provides a driving circuit having a plurality of output voltages, the driving circuit having a voltage generator and a plurality of digital / analog converters. The voltage generator is configured to generate a plurality of intensity reference voltages. Each of the digital / analog converters converts the digital image signal according to the supplied gray level reference voltage and the received digital image signal to obtain a plurality of analog signals for displaying an image corresponding to the digital image signal. In the situation where the same digital code is used corresponding to the digital image signal, the values of the plurality of gray scale reference voltages supplied to the digital / analog converter are not completely the same.

  The driving circuit having a plurality of output voltages further includes a data latch, and the data latch has a plurality of address channels for storing a digital image signal therein.

  The driving circuit having a plurality of output voltages further includes a shift register that receives the timing pulse signal and is triggered by the trigger signal. This shift register controls the digital image signal so that it is sequentially stored in the address channel of the data latch.

  In the driving circuit having a plurality of output voltages, the value of each reference voltage supplied to the digital / analog converter is adjusted according to the color characteristics. According to one embodiment, the values of the respective reference voltages are adjusted according to the red, green and blue color characteristics, and in other embodiments according to the red, green, blue and white color characteristics. Have been adjusted.

  In one embodiment, the present invention is a drive circuit having a plurality of output voltages, comprising at least a first digital / analog converter, a second digital / analog converter, and a third digital / analog converter. Provided is a drive circuit. The digital / analog converter receives a plurality of gray scale reference voltages, converts the digital image signal, and obtains a plurality of analog signals corresponding to the digital image signal. When the digital image signals received by the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter are the same, depending on the respective respective intensity reference voltages, Analog signals whose values are not completely identical to one another can be obtained, and an image corresponding to the digital image signal can be displayed by this analog signal.

  The driving circuit having a plurality of output voltages further includes a voltage generator for generating the gray level reference voltage.

  In the driving circuit having a plurality of output voltages, the gray scale reference voltage may be supplied by an external supply source outside the driving circuit.

  In the drive circuit having a plurality of output voltages, the gray level reference supplied to the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter At least two of the voltage combinations are different.

  In the drive circuit having a plurality of output voltages, the gray level reference supplied to the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter The combination of voltages is individually adjusted according to the color characteristics. According to one embodiment, the value of each reference voltage is adjusted according to the color characteristics of red, green and blue, and in other embodiments, the value of each reference voltage is red, green, It is adjusted according to the color characteristics of blue and white.

  In the drive circuit having a plurality of output voltages, the gray level reference supplied to the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter The combination of voltages is individually adjusted according to the characteristics of the filter.

  The driving circuit having a plurality of output voltages further includes a data latch, and the data latch has a plurality of address channels for storing a digital image signal therein.

  The driving circuit having a plurality of output voltages further includes a shift register that receives the timing pulse signal and is triggered by the trigger signal. This shift register controls the digital image signal so that it is sequentially stored in the address channel of the data latch.

  According to one embodiment, the present invention provides a display driver circuit comprising a data latch and a plurality of digital / analog converters, wherein the data latch stores a digital image signal therein. And a plurality of digital / analog converters respectively convert the digital image signal in accordance with the supplied gray level reference voltage and the received digital image signal to correspond to the digital image signal. A plurality of analog signals for displaying an image are obtained. In the situation where the same digital code is used corresponding to the digital image signal, the values of the plurality of gray scale reference voltages supplied to the digital / analog converter are not completely the same.

  The display device driving circuit further includes a voltage generator for generating the gray level reference voltage.

  The display device driving circuit further includes a shift register that receives the timing pulse signal and is triggered by the trigger signal. This shift register controls the digital image signal so that it is sequentially stored in the address channel of the data latch.

  In the display device driving circuit, the value of each reference voltage supplied to the digital / analog converter is adjusted according to the color characteristics. According to one embodiment, the values of the respective reference voltages are adjusted according to the red, green and blue color characteristics, and in other embodiments according to the red, green, blue and white color characteristics. Have been adjusted.

  According to one embodiment, the present invention includes a step of storing a digital image signal, and a plurality of digital / analog converters convert the digital image signal according to a supplied gray scale reference voltage and the received digital image signal. And obtaining a plurality of analog signals for displaying an image corresponding to the digital image signal. In the situation where the same digital code is used corresponding to the digital image signal, the values of the plurality of gray scale reference voltages supplied to the digital / analog converter are not completely the same.

  In the driving method described above, the value of each reference voltage supplied is adjusted according to the color characteristics. According to one embodiment, the values of the respective reference voltages are adjusted according to the red, green and blue color characteristics, and in other embodiments according to the red, green, blue and white color characteristics. Have been adjusted.

  The present invention provides a driving means having a device in which output voltages are individually controlled, and a driving method thereof. The driving means and driving method of the present invention can individually adjust the transmission characteristics of each color of the color display device including red, green and blue instead of specially processing the image signal. The chromatic aberration problem can be solved without calculating and compensating the input image signal as required in conventional designs, or both circuits such as drivers with higher resolution ratios that require conventional technology, special This can be solved without using a simple timing sequence controller or a plurality of sets of reference voltage sources. The purpose of individually adjusting the transmission characteristics of each color of the color display device can be achieved in this way, and as a result, a complex system can be simplified and thus the manufacturing costs can be reduced.

  A conventional color display driver is shown in the schematic block diagram of FIG. However, the color display device driver is also provided in the embodiment of the present invention. The color display device driver includes a shift register and a data latch. The shift register is configured to receive a timing pulse signal supplied by an external timing controller and to be triggered by a trigger signal. The shift register controls a digital image signal corresponding to the digital image data, and sequentially delivers the digital image signal to each address channel of the data latch. The data latch supplies digital image data to each of a plurality of digital / analog converters for use. The digital / analog converter converts the digital image signal according to the supplied reference voltage and the digital image signal provided by the data latch to obtain a plurality of analog signals for output to the color display device. A color display device is, for example, an LCD display, a light emitting diode (LED) display device, or any other display driven by a matrix driver, such a display device having a plurality of pixels arranged in a matrix. And displaying an image corresponding to the digital image signal corresponding to the received analog signal. According to one aspect of this embodiment, the data latch is, for example, a flip-flop.

  According to one embodiment of the driving means and the driving method of the present invention having a plurality of output voltages, the color characteristics or filter characteristics of each pixel can be obtained under the situation where the same digital code is used. Accordingly, the control voltage of the driver can be individually adjusted, and the gray level can be further adjusted. Better color performance can be achieved after compensation has been performed. Therefore, the display quality is improved and the cost is reduced.

  The present invention requires improvements to the digital / analog converter portion of the conventional driver shown in FIG. FIG. 4 is an embodiment of a 2-bit digital / analog converter according to the present invention. Referring to FIG. 4, for ease of explanation, only three digital / analog converters 410, 420 and 430 are provided and illustrated according to the embodiment. However, those skilled in the art will appreciate that more or less digital / analog converters may be used to meet a particular requirement. Each of the first digital / analog converter 410, the second digital / analog converter 420, and the third digital / analog converter 430 receives the digital image signals D0 and D1, and these digital image signals D0 and D1. In response to this, analog signals Vr_out, Vg_out and Vb_out for color display are output.

  According to one embodiment of the driving means of the present invention having a plurality of output voltages, the driver can be used depending on the color characteristics or filter characteristics of each pixel under the situation of using the same digital code. The control voltage can be adjusted individually, and the lightness can be further adjusted. In order to achieve this goal, one embodiment of the present invention provides a higher intensity reference voltage. As shown in FIG. 2, three conventional digital / analog converters support a 2-bit digital code, and only four grayscale reference voltages V1, V2, V3 and V4 are required. According to one embodiment of the present invention, the digital / analog converter is supplied with a number of grayscale reference voltages V1, V2, V3, V4, V5, V6, V7 and V8. However, the present invention is not intended to limit the number of shade reference voltages. If the number of grayscale reference voltages is greater than the square of the number of bits of the digital code (here 2 ^ 2 = 22 = 4), it is within the scope of the technical scope of the present invention. For example, it is possible to use six reference voltages V1, V2, V3, V4, V5 and V6. The reference voltage can be generated by the voltage generator 440 or can be provided by a device external to the driver. The voltage generator 440 can generate a large number of shade reference voltages.

  According to such a design, for example, for the first digital / analog converter 410, the gray scale reference voltages V1, V2, V4, and V7 are set to the first digital / analog according to the optical characteristics of the display device. This is supplied to the converter 410. According to the digital codes D0 and D1 of the digital image signal and the gray scale reference voltages V1, V2, V4 and V7, the first digital / analog converter 410 outputs an analog signal Vr_out to the LCD display. Similarly, the grayscale reference voltages V1, V3, V5, and V7 are separately supplied to the second digital / analog converter 420 according to the optical characteristics of the display device. According to the digital codes D0 and D1 of the digital image signal and the gray scale reference voltages V1, V3, V5 and V7, the second digital / analog converter 420 outputs the analog signal Vg_out to the LCD display. The third digital / analog converter 430 is supplied with gradation reference voltages V1, V4, V6 and V8 according to the optical characteristics of the display device. According to the digital codes D0 and D1 of the digital image signal and the gray scale reference voltages V1, V4, V6 and V8, the third digital / analog converter 430 outputs the analog signal Vb_out to the color display device for displaying an image. .

  In the configuration like the design of this embodiment, instead of specially processing the image signal, the driver of the present invention in which the output voltage is individually controlled allows the display of a color display device such as red, green, blue or white. Any specific color transmission characteristics can be adjusted individually. The purpose of individually adjusting the transmission characteristics of each color of a color display device can be achieved without the need for a circuit such as the special timing sequence controller described above, or multiple sets of reference voltage supply sources, and thus a complex system. Can be simplified, and the manufacturing cost can be reduced.

  According to one embodiment of the present invention, the plurality of intensity reference voltages are V1, V2, V3, V4, V5, V6, V7 and V8, from which various combinations of intensity reference voltages can be selected. it can. The shade of the digital / analog converter can also be individually adjusted in advance according to the characteristics of the color display device. For example, the combination of intensity reference voltages for the first digital / analog converter 410 includes intensity reference voltages V 1, V 2, V 4 and V 7, and the intensity for the second digital / analog converter 420. The combination of reference voltages includes intensity reference voltages V1, V3, V5 and V7, and the combination of intensity reference voltages for the third digital / analog converter 430 includes intensity reference voltages V1, V4, V6 and V8 is included. As shown in FIG. 5, when the digital image signals D0 and D1 of the same digital code are input to the driver of the present invention, the analog output signals Vr_out, Vg_out and Vb_out individually indicate the displayed red, green and blue shades. Will not be the same to adjust to. The transmission characteristics of the individual colors considered for individually adjusting the intensity of the digital / analog converter are not limited to those based on red, green and blue, but based on red, green, blue and white It should be noted that they may be based on more color characteristics.

  Other changes or adjustments can be made to the preferred embodiments of the invention described above to suit specific requirements. The disclosure herein is intended to illustrate the invention without limiting the scope of the invention. All modifications are intended to be embraced in the appended claims or equivalents given in the claims if they incorporate the invention disclosed in the preferred embodiments.

  The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the following detailed description, serve to explain the principles of the invention.

It is the schematic block diagram which showed the driver for normal color display apparatuses. FIG. 2 schematically illustrates a conventional simple 2-bit digital / analog converter of the normal driver according to FIG. 1. It is the figure which showed schematically the relationship between the analog signal output and the input gray level about the conventional 2-bit digital / analog converter. 1 is an embodiment of a 2-bit digital / analog converter according to the present invention. It is the figure which showed roughly the relationship between the output analog signal and the input gray level about the 2-bit digital / analog converter of this invention.

Explanation of symbols

100 Driver 110 Shift register 120 Data latch 130 Analog converter 150 Color display panel 410 Analog converter 420 Analog converter 430 Analog converter 440 Voltage generator

Claims (31)

A drive circuit having a plurality of output voltages,
A voltage generator configured to generate a plurality of reference voltages; and a plurality of digital / analogs configured to receive a plurality of digital image signals and generate a plurality of analog signals according to the reference voltages and the digital image signals An analog converter,
A drive circuit in which the value of the reference voltage supplied to the digital / analog converter is not completely the same under the situation where the same digital code is used corresponding to the digital image signal.   2. The drive circuit having a plurality of output voltages according to claim 1, further comprising a data latch having a plurality of address channels for storing the digital image signal therein.   3. The shift register according to claim 2, further comprising a shift register configured to receive a timing pulse signal, be triggered by a trigger signal, and further control the digital image signal to be sequentially delivered to the address channel of the data latch. A drive circuit having a plurality of output voltages as described.   The drive circuit having a plurality of output voltages according to claim 1, wherein the value of each reference voltage supplied to the digital / analog converter is adjusted according to color characteristics.   5. The drive circuit having a plurality of output voltages according to claim 4, wherein the values of the respective reference voltages are adjusted according to the color characteristics of red, green, and blue.   5. The drive circuit having a plurality of output voltages according to claim 4, wherein the values of the respective reference voltages are adjusted according to the color characteristics of red, green, blue, and white. A drive circuit having a plurality of output voltages,
A first digital / analog converter,
A second digital / analog converter, and a third digital / analog converter,
The digital / analog converter is configured to receive a plurality of grayscale reference voltages, convert a digital image signal, and obtain a plurality of analog signals according to the digital image signal;
When the digital image signals received by the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter are the same, the respective respective intensity reference voltages are Correspondingly, a drive circuit that obtains analog signals whose values are not exactly the same.   The driving circuit having a plurality of output voltages according to claim 7, further comprising a voltage generator for generating the gray level reference voltage.   8. The drive circuit having a plurality of output voltages according to claim 7, wherein the gray scale reference voltage is provided by an external source outside the drive circuit.   At least two of the grayscale reference voltage combinations supplied to the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter are different. A drive circuit having a plurality of output voltages according to claim 7.   A combination of gray scale reference voltages supplied to the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter is individually adjusted according to color characteristics. A drive circuit having a plurality of output voltages according to claim 7.   The drive circuit having a plurality of output voltages according to claim 11, wherein the values of the respective reference voltages are adjusted according to color characteristics of red, green, and blue.   The drive circuit having a plurality of output voltages according to claim 11, wherein the values of the respective reference voltages are adjusted according to the color characteristics of red, green, blue and white.   The combination of the gray scale reference voltages supplied to the first digital / analog converter, the second digital / analog converter, and the third digital / analog converter is individually set according to the characteristics of the filter. 8. A drive circuit having a plurality of output voltages according to claim 7, wherein the drive circuit is adjusted.   8. The driving circuit having a plurality of output voltages according to claim 7, further comprising a data latch having a plurality of address channels for storing the digital image signal therein.   16. The shift register of claim 15, further comprising a shift register that receives a timing pulse signal, is triggered by a trigger signal, and is further configured to control the digital image signal to be sequentially delivered to the address channel of the data latch. A drive circuit having a plurality of output voltages as described.   16. The driving circuit having a plurality of output voltages according to claim 15, wherein the data latch is a flip-flop. A drive circuit having a plurality of output voltages,
A data latch having a plurality of address channels for storing a plurality of digital signals which are N-bit digital signals; and a plurality of analog signals in accordance with the plurality of reference voltages and the digital signals receiving the plurality of digital signals A plurality of digital / analog converters configured to generate
A drive circuit in which the number of reference voltages is greater than the number of possible combinations in the digital signal, ie 2 ^ N.   19. The drive circuit having a plurality of output voltages according to claim 18, further comprising a voltage generator for generating the plurality of reference voltages.   19. A shift register is further provided that receives a timing pulse signal, is triggered by a trigger signal, and is further configured to control the plurality of digital signals to be sequentially delivered to the address channel of the data latch. A driving circuit having a plurality of output voltages described in 1.   19. The plurality of output voltages according to claim 18, wherein the values of the respective reference voltages supplied to the digital / analog converter are adjusted according to characteristics of a receiver device receiving the plurality of reference voltages. Driving circuit. A drive circuit for a display device,
A data latch having a plurality of address channels for storing digital image signals internally;
A plurality of digital / analog converters configured to receive the digital image signal and generate a plurality of analog signals in accordance with a plurality of reference voltages and the digital image signal;
A display device drive circuit in which the value of a reference voltage supplied to the digital / analog converter is not completely the same under the situation where the same digital code is used corresponding to the digital image signal.   The display device drive circuit according to claim 22, further comprising a voltage generator for generating the reference voltage.   23. The shift register according to claim 22, further comprising a shift register configured to receive a timing pulse signal, be triggered by a trigger signal, and further control to deliver the digital image signal sequentially to the address channel of the data latch. The drive circuit for display apparatuses as described.   23. The display device drive circuit according to claim 22, wherein the value of each reference voltage supplied to the digital / analog converter is adjusted according to color characteristics.   26. The display device drive circuit according to claim 25, wherein the values of the respective reference voltages are adjusted according to the color characteristics of red, green, and blue.   26. The display device drive circuit according to claim 25, wherein the values of the respective reference voltages are adjusted according to the color characteristics of red, green, blue and white. Receiving a digital image signal; and converting the digital image signal to obtain a plurality of analog signals according to a plurality of intensity reference voltages and the digital image signal;
A driving method in which the values of the plurality of gray scale reference voltages supplied to the digital / analog converter are not completely the same under the situation where the same digital code is used corresponding to the digital image signal.   29. The driving method according to claim 28, wherein each of the supplied reference voltages is adjusted according to color characteristics.   29. The driving method according to claim 28, wherein each of the supplied reference voltages is adjusted according to color characteristics of red, green, and blue.   29. The driving method according to claim 28, wherein each of the supplied reference voltages is adjusted according to color characteristics of red, green, blue and white.

Images