JP2009128455A - Method of expanding color reproduction range of color display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make the screen of a display further fascinating by expanding a color reproduction range. <P>SOLUTION: The method includes: a step of dividing groups of primary color light sources of respective colors of the color display and beam intensity regulating mechanisms corresponding thereto, by color leak conditions of discrete response spectra, thereby separating color separation sub-screens from the color screens to minimize the color leak of the response spectra of the beam intensity regulating mechanisms of the primary color light sources of the same group and the spectra of the primary color light sources of other group; and a step of performing the control in such a manner that the primary color light sources of only the one group emit light simultaneously in a single time section depending on the conditions of the grouping of the color separation sub-screens and the beam intensity regulating mechanisms of the primary colors of the colors respectively corresponding thereto turn on and at this time, all of other groups turn off, and sequentially operating the mechanisms group by group to compose the perfect color screens of mixed colors with time in the final and making the signals displayed on the sub-screens synchronous. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for enlarging a color display color reproduction range, and more particularly to a backlight driving method in which a display screen becomes more glossy by enlarging the color reproduction range.

  The conventional cold cathode tube (CCFL) backlight source and the new RGB LED backlight source have a blue color better because the cold cathode tube has a worse red and green color representation and a better blue color representation. As a result, the color reproduction range of the cold-cathode tube backlight light source can achieve only 70% of the color television broadcasting standard (NTSC), and even a newly developed cold-cathode tube backlight light source The color reproduction range can only achieve 95% of the color television broadcasting standard (NTSC). However, the LED backlight light source produced by the RGB mixed color method can easily achieve a color reproduction range of 120% or more of the color television broadcasting standard (NTSC) in theory. We are developing a liquid crystal display using the three primary color LEDs as the backlight source.

  In fact, the current color filter (CF) has a very severe color leakage in the transmission spectrum of blue light and green light, so the blue light that the LED backlight expresses through the color filter leaks from the green color filter. Similarly, when expressing green light, the green light leaks out of the blue color filter, thus greatly reducing the purity of the three primary colors of the display and the color reproduction range of the display. There is a problem to become.

  In order to solve the problem of lack of display color saturation, developers such as Yoichi Taira proposed a color filterless color display in 2003, and light emitting diodes in the backlight led to the display. Control expression color directly. Meanwhile, at the Taiwan Flat Display Show held in June 2006, Chunghwa Picture Tubes announced a 32-inch color filterless LED backlight LCD color display.

  A color filter-less display is one that does not use any color filter. The principle is that a large number of colors can be synthesized with a small number of primary light sources by adopting a temporal color-mixing method instead of the original spatial color-mixing method. is there. Spatial color mixing means that each pixel pixel in a color display emits a light beam of each primary color (for example, red light, green light, or blue light) so that the user can see different colors on the screen. On the other hand, color mixing is incident on the user's eyes. On the other hand, temporal color mixing is performed by switching light of each primary color (for example, red light, green light, and blue light) sequentially and quickly at the same pixel pixel. If it is faster than the visual residual, it is possible to achieve a temporal color mixing effect. A color display that employs such a temporal color mixture method uses LEDs having a plurality of colors (for example, red light, green light, and blue light LEDs) as a backlight light source, and blinks these LEDs intermittently to generate light. The desired face color can be expressed on the screen by controlling the luminous intensity of each face color with the adjusting liquid crystal.

  The color filterless color display that employs the above temporal color mixing method has the advantage that the light utilization rate can be increased without using a color filter, and the backlight light source sequentially turns on LEDs of each color. Since it blinks, it consumes less power, so the heat dissipation problem of the LED backlight light source can be solved easily. However, such a color filterless LED backlight / liquid crystal color display does not have a good color mixing effect unless the response speed of the liquid crystal itself is fast, but its manufacturing technology is more difficult and cannot be produced on the current production line. . On the other hand, a technology using six-color LEDs has been developed, but the control of color expression is greatly complicated, and the above problem still cannot be solved.

  The invention of the present application made to achieve the above object is to divide the primary color light source of each color of the color display and the corresponding light intensity adjustment mechanism into groups according to the color leakage situation of the individual response spectrum. Separating the color separation sub-screen from the color screen, wherein the color leakage between the response spectrum of the light intensity adjusting mechanism of the primary color light source of the same group and the spectrum of the primary color light source of another group is minimized, and the above color Depending on the grouping situation of the separation sub-screen, only one group of primary color light sources emits simultaneously in a single time interval, and the light intensity adjustment mechanism of the corresponding primary color is turned on. Control different groups to be turned off, operate sequentially for each group, and finally, complete color mixing with time mixing To the composition of the over screen, and summarized in that a method of enlarging a color display color reproduction range, which comprises the steps of the synchronizing signal displayed on the sub-screen, the.

  In the invention of the present application, the color separation sub-screen can be divided into a red-green sub-screen and a red-blue sub-screen, and the red color of the red-green sub-screen and the red-blue sub-screen Since the LED backlight is not severely leaked in the spectrum, no special processing is required, and the liquid crystal layer displays the red-green sub-screen to synchronize the signals displayed on the sub-screen. 2. The blue LED backlight light source is turned off when the liquid crystal layer is displaying a red-blue sub-screen, and the green LED backlight light source is turned off when the liquid crystal layer is displaying a red-blue sub-screen. The main point is that it is a method for expanding the color display color reproduction range.

  In the invention of the present application, the step of synchronizing the signals displayed on the sub-screens described above is performed when the total switching time of each color separation sub-screen is shorter than the response speed of the visual residual of the human eye. The gist of the present invention is the color display color reproduction range expansion method according to claim 1, wherein a color screen with an expanded range can be composed.

  According to the method for expanding the color display color reproduction range of the present invention, there is an effect that the screen of the display is further glossy.

  Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  As shown in FIGS. 1 and 2, the method for expanding the color display color reproduction range of the present invention includes the following steps when the human eye receives a color signal of the screen.

  (1) Step of separating the color separation sub-screen from the color screen (S1): The primary color light source of each color of the color display and the light intensity adjustment mechanism corresponding to each color light source according to the color leakage situation of the individual response spectrum Dividing the group minimizes the color drift between the response spectrum of the light intensity adjustment mechanism of the primary color light source of the same group and the spectrum of the primary color light source of another group, and each primary color light of each group has the same color separation.・ The sub screen is composed, and the group quantity is the same as the color separation sub screen quantity. The color display is a device that transmits the color signal of the screen to the user's eyes, and the light intensity adjustment mechanism of the primary light source of the color display has the ability to adjust the light intensity for each primary color of the color separation. In the case of a liquid crystal display, it is a combination of the color resistance of each face color, a liquid crystal and a polarizing plate.

  (2) Synchronizing signals displayed on the sub screen (S2): Depending on the grouping situation of the color separation sub screen, only one group of primary color light sources emits light simultaneously in a single time interval. And the light intensity adjustment mechanism of the primary color of the corresponding color is turned on, at this time, all other groups are controlled to be turned off, and each group is operated sequentially, and finally it is complete with temporal color mixing To create a color screen.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.

  Each color screen 10 has red, green, and blue color separation information. When the color screen 10 is divided into a red-green sub-screen 11 and a red-blue sub-screen 12, the green light source 21 backlight causes the color filter 30 to be used. When the blue light source pixel backlight 23 passes through the color filter 30, the corresponding blue liquid crystal pixel pixel 24 is turned off when the blue light source 20 backlight passes through the color filter 30. Thus, the blue light source 20 and the green light source 21 in the backlight blink at different times, thereby preventing color leakage, and the red light source 22 backlight has a spectral color leakage. Is not relatively harsh and does not require special treatment, while the blinking times of the blue light source 20 and the green light source 21 are human eyes. Since faster than Satoru residue, it is possible to achieve the effect of temporal color mixing.

  The blue light source 20 includes a blue light LED, the green light source 21 includes a green light LED, and the red light source 22 includes a red light LED.

  When the backlight of the green light source 21 emits light, the corresponding blue liquid crystal pixel pixel 23 is turned off. Then, the backlight of the blue light source 20 does not leak out on the expressed green screen, and in the next time interval. When the blue light source 20 backlight is emitting light, the corresponding green liquid crystal pixel pixel 24 is turned off, so that the green light source 21 backlight does not leak into the blue screen to be expressed, and the blue light source 20 and If the blinking time of the green light source 21 is made faster than the visual residual of the human eye, the temporal color mixing effect can be achieved. As a result, the purity of the three primary colors of the display is greatly improved, and the color reproduction range of the display is also greatly improved.

  Further, the advantage of the present invention is that the color reproduction range can be expanded without changing the current configuration of the LED backlight display, and the response speed of the liquid crystal is not strictly required, and the production is simpler.

The experimental backlight module of the present invention uses an LED as a backlight light source, and its specifications and characteristics are shown in Table 1.

  As shown in FIG. 5, by measuring the spectral distribution of the three-color LED with an integrating ball and theoretically expecting the three-color LED backlight, a conventional LED backlight and a wide color reproduction range backlight are obtained. As shown in FIG. 6, the color reproduction range of the conventional LED backlight is 100.28% NTSC, and the wide color reproduction range backlight of the present invention is calculated. Therefore, the color reproduction range of the wide color reproduction range backlight of the present invention is increased by about 17% compared to the conventional LED backlight, and the color reproduction range of the color filterless LCD is as follows. Is 119.02% NTSC, so the color reproduction range of the wide color reproduction range backlight of the present invention was 1.5% less than the color filterless LCD. Wide color reproduction range backlight technology greatly increases the color reproduction range of the display, the color reproduction range is almost the same as the three-color LCD backlight, and does not require a significant change in the display configuration .

  As shown in FIGS. 7 and 8, the experimental liquid crystal panel and backlight of the present invention uses a 19-inch LCD manufactured by Samsung, and uses the liquid crystal panel 40, a color filter and a diffusion film, The three-color LED backlight module 41 is assembled by removing the cold-cathode tube backlight light source, and is electrically connected to the panel drive circuit 42 and the power supply unit 43. As shown in FIG. The light sources 44 are arranged in 3 groups and 3 groups, and each group is composed of four LEDs of RGGB (red, green, green, and blue), and in order to improve the color mixing of the backlight light source, a reflection type is provided in the emission hole of each LED. A diffusion film is attached.

  Fig. 9 is a comparison diagram of the color reproduction range of a conventional LED backlight display and a wide color reproduction range backlight. The outermost line is the NTSC standard color reproduction range and is connected by a mark (●). 9 is the color reproduction range of the display that does not use the wide color reproduction range backlight technology, and the line connected with the mark (◇) is the color reproduction range of the display that uses the wide color reproduction range backlight technology. As is clear from the above, the line range connected with the mark (◇) is wider than the line connected with the mark (●) and surrounds the standard color reproduction range of NTSC. According to the data, the color reproduction range is 99% NTSC expanded to 116.76% NTSC, that is, the color reproduction range increased to almost 18% NTSC. This is because the wide color reproduction range backlight technology increased the color reproduction range. In addition, it proved that the screen of the display becomes more glossy.

  In the present invention, the color reproduction range can be expanded without using a color filter, and the current production line can be used for the system configuration. As a result, regardless of which display is used and the response time of the liquid crystal of the display, each liquid crystal pixel pixel can mix various facial colors, thereby expanding the color reproduction range of the display. It becomes like this.

3 is a flowchart of the present invention. FIG. 3 is a schematic diagram illustrating steps of the present invention. It is the schematic which shows the application of the Example of this invention. It is the schematic which shows the state in which the blue backlight and green backlight of this invention are divided over time. It is the schematic which shows distribution of the spectrum of red green blue three-color LED of this invention. It is a comparison figure of the color reproduction range of three display technologies. FIG. 2 is a schematic diagram of the construction of the apparatus of the present invention. It is the schematic which shows the structure of the LED backlight light source of this invention. It is a comparison figure of the color reproduction range of the conventional LED backlight display and this invention.

Explanation of symbols

10 Color screen 11 Red-green sub-screen 12 Red-blue sub-screen 20 Blue light source 21 Green light source 22 Red light source 23 Liquid crystal pixel pixel 24 Liquid crystal pixel pixel 30 Color filter 40 Liquid crystal panel 41 Backlight module 42 Drive circuit 43 Power supply 44 Backlight light source

Claims (3)

By dividing the primary color light source of each color of the color display and the corresponding light intensity adjustment mechanism into groups according to the color leakage situation of the individual response spectrum, the response spectrum of the light intensity adjustment mechanism of the primary light source of the same group Separating the color separation sub-screen from the color screen so that color leakage from the spectrum of another group of primary color light sources is minimized;
Depending on the grouping situation of the above color separation sub-screen, only one group of primary color light sources emits light simultaneously in a single time interval, and the light intensity adjustment mechanism of the corresponding primary color is turned on. Controlling all other groups to be turned off, sequentially operating by group, and finally composing a complete color screen with temporal color mixing, synchronizing the signals displayed on the sub-screens, and , Including,
Color display color reproduction range expansion method. The color separation sub-screen can be divided into a red-green sub-screen and a red-blue sub-screen,
The red LED backlight of the red-green sub-screen and the red-blue sub-screen does not need to be specially processed because the color leakage of the spectrum is not severe.
Synchronizing the signal displayed on the sub screen is to turn off the blue LED backlight source when the liquid crystal layer is displaying the red-green sub screen and the liquid crystal layer to display the red-blue sub screen. 2. The method of expanding a color display color reproduction range according to claim 1, wherein the green LED backlight light source is turned off when the color display backlight is on.   In the step of synchronizing the signals displayed on the sub-screen, the color display color reproduction range is expanded when the total switching time of each color separation sub-screen is shorter than the response speed of visual residual of human eyes. The color display color reproduction range expansion method according to claim 1, wherein a color screen can be composed.

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