JP2007108285A

JP2007108285A - Liquid crystal display apparatus

Info

Publication number: JP2007108285A
Application number: JP2005297467A
Authority: JP
Inventors: Masashi Okuma; 雅志大熊
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2005-10-12
Filing date: 2005-10-12
Publication date: 2007-04-26

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display apparatus that corrects misalignment in chromaticity output on a screen depending on a time period from starting the power supply and that reproduces accurate colors. <P>SOLUTION: The display apparatus is equipped with: a first control circuit where color signal components of the image signal are input; a matrix circuit where the color signal components are input, the color signal component values are multiplied by the respective coefficients and their sum is output; a liquid crystal driving circuit driven by the output of the matrix circuit; a liquid crystal panel driven by the liquid crystal driving circuit; and moreover, a counter to measure the time from starting the power supply; and a second control circuit that outputs a signal to the counter that the power supply is started on the first control circuit and that changes the component ratio of the color signal components of the matrix circuit according to the counted value by the counter, to compute a correction value on the chromaticity upon starting and to change the component ratio of the matrix circuit 4 by the computation result. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、ＰＣ、ワープロなどのＯＡ機器やテレビなどのディスプレイとして用いられる液晶表示装置に関するものである。 The present invention relates to a liquid crystal display device used as a display for OA devices such as PCs and word processors, and televisions.

マトリクス回路による各色信号成分処理を、制御回路により入力変動に応じてその成分比を変えることにより、液晶デバイスに固有な旋光分散を補償し、液晶の駆動電圧レベルが変化しても色度点を一定になるようにしていた。
特開平５−２７７１１号公報 Each color signal component processing by the matrix circuit is compensated for the optical rotation dispersion inherent to the liquid crystal device by changing the component ratio according to the input fluctuation by the control circuit, and the chromaticity point can be set even if the drive voltage level of the liquid crystal changes. It was supposed to be constant.
Japanese Patent Laid-Open No. 5-27711

液晶表示装置の特性から、電源起動時からの時間によって画面に出力される色度がずれるという課題があった。 Due to the characteristics of the liquid crystal display device, there is a problem that the chromaticity output on the screen is shifted depending on the time from the start of the power supply.

本発明は前記課題に鑑み、液晶表示装置が起動してからの時間によって生じる色度ずれを起動からの時間を記憶するカウンター値を元に前記マトリクス回路による各色信号成分処理の成分比を補正することによって正確な色再現をおこなうことを特徴としたものである。 In view of the above-described problems, the present invention corrects the component ratio of each color signal component processing by the matrix circuit based on a counter value that stores a chromaticity shift caused by the time from the start of the liquid crystal display device and stores the time from the start. In this way, accurate color reproduction is performed.

前記課題を解決するために、本発明の液晶表示装置は、電源が起動された時間をカウンターによって計測し、そのカウンター値によって各色信号成分処理の成分比を変更することで正確な色再現をおこなうことを特徴としたものである。 In order to solve the above problems, the liquid crystal display device of the present invention performs accurate color reproduction by measuring a power-on time with a counter and changing the component ratio of each color signal component processing according to the counter value. It is characterized by that.

以上説明したように、液晶表示装置が起動してからの時間によって生じる色度ずれを起動からの時間を記憶するカウンター値を元に前記マトリクス回路による各色信号成分処理の成分比を補正することによって正確な色再現をおこなう液晶表示装置を提供することが可能になる。 As described above, by correcting the component ratio of each color signal component processing by the matrix circuit based on the counter value that stores the time from the start of the chromaticity shift caused by the time from the start of the liquid crystal display device It is possible to provide a liquid crystal display device that performs accurate color reproduction.

本発明の請求項１に記載の液晶表示装置は、
液晶表示装置が起動してからの時間を計測するカウンターと、カウンタ出力を用いて色信号の成分比を補正するマトリクス回路とを少なくとも備え、起動時の色再現をおこなうものである。 The liquid crystal display device according to claim 1 of the present invention is
At least a counter that measures the time since the liquid crystal display device is activated and a matrix circuit that corrects the color signal component ratio using the counter output are provided, and color reproduction at the time of activation is performed.

請求項２に記載の発明は、映像信号の各色信号成分が入力される第１の制御回路と、各色信号成分が入力され各色信号成分値に各々係数が掛けられてその和を出力するマトリクス回路と、マトリクス回路の出力により駆動される液晶駆動回路と、液晶駆動回路により駆動される液晶パネルとを具備し、電源起動時からの時間を計測するカウンターと、第１の制御回路に電源起動がなされたことをカウンターに出力しマトリクス回路の各色信号成分処理の成分比をカウンターがカウントした値に応じて変化させる第２の制御回路を持つものである。 According to a second aspect of the present invention, there is provided a first control circuit to which each color signal component of a video signal is input, and a matrix circuit for inputting each color signal component and multiplying each color signal component value by a coefficient and outputting the sum. A liquid crystal driving circuit driven by the output of the matrix circuit, and a liquid crystal panel driven by the liquid crystal driving circuit, and a counter for measuring the time from the power activation, and the first control circuit being activated It has a second control circuit that outputs to the counter what has been done and changes the component ratio of each color signal component processing of the matrix circuit in accordance with the value counted by the counter.

以下、本発明の一実施の形態について、図１を用いて説明する。 Hereinafter, an embodiment of the present invention will be described with reference to FIG.

図１において、１、２、３は入力端子、４はマトリクス回路、５は第２の制御回路
６、７、８はそれぞれ入力端子１、２、３に対応する出力端子９は信号電極駆動回路、１０は走査電極駆動回路、１１は液晶パネル、１２がカウンターである。 In FIG. 1, 1, 2 and 3 are input terminals, 4 is a matrix circuit, 5 is a second control circuit, 6, 7 and 8 are output terminals corresponding to the input terminals 1, 2, and 3, respectively. Reference numeral 10 denotes a scanning electrode driving circuit, 11 denotes a liquid crystal panel, and 12 denotes a counter.

（実施の形態１）
図１において、入力端子１、２、３にはそれぞれ映像信号の各色信号成分であるＲ、Ｇ、Ｂ信号が入力される。第２の制御回路５では、入力されたＲ、Ｇ、Ｂ信号から輝度信号レベル値を求める。輝度信号レベル値をＹ、入力のＲ、Ｇ、Ｂ信号のレベル値をそれぞれＲＩＮ，ＧＩＮ，ＢＩＮとすると、このＹの値にもとづいて制御回路５からマトリクス回路４に制御信号が与えられる。マトリクス回路４では制御信号によりＲ、Ｇ、Ｂ信号を次式のように変換する。 (Embodiment 1)
In FIG. 1, R, G, and B signals that are color signal components of video signals are input to input terminals 1, 2, and 3, respectively. The second control circuit 5 obtains the luminance signal level value from the inputted R, G, B signals. If the luminance signal level value is Y and the input R, G, and B signal level values are RIN, GIN, and BIN, respectively, a control signal is supplied from the control circuit 5 to the matrix circuit 4 based on the Y value. The matrix circuit 4 converts the R, G, and B signals by the control signal as follows.

ＲＯＵＴ１＝ａ１１・ＲＩＮ＋ａ１２・ＧＩＮ＋ａ１３・ＢＩＮ
ＧＯＵＴ１＝ａ２１・ＲＩＮ＋ａ２２・ＧＩＮ＋ａ２３・ＢＩＮ
ＢＯＵＴ１＝ａ３１・ＲＩＮ＋ａ３２・ＧＩＮ＋ａ３３・ＢＩＮ
ここで、係数ａ１１、ａ１２、…、ａ３３は制御信号により値が変化する。また、液晶表示装置の電源が起動することにより、第２の制御回路５がカウンター１２に電源が起動されたことを出力し、前記カウンター１２は第２の制御回路５の出力からカウントをはじめ、その値を前記第２の制御回路５に出力する。その出力された値より時間変化における各色度変化の補正係数を求める。（ここでカウント値をｃｏｕｎｔとする。）
ｃｏｕｎｔＲ＝ｆｒ（ｃｏｕｎｔ）
ｃｏｕｎｔＧ＝ｆｇ（ｃｏｕｎｔ）
ｃｏｕｎｔＢ＝ｆｂ（ｃｏｕｎｔ）
この補正係数と液晶パネル１１の旋光分散を補償するように設定されたＲＯＵＴ１、ＧＯＵＴ１、ＢＯＵＴ１を掛ける。 ROUT1 = a11 · RIN + a12 · GIN + a13 · BIN
GOUT1 = a21 · RIN + a22 · GIN + a23 · BIN
BOUT1 = a31 · RIN + a32 · GIN + a33 · BIN
Here, the values of the coefficients a11, a12,..., A33 change according to the control signal. Further, when the power source of the liquid crystal display device is activated, the second control circuit 5 outputs that the power source is activated to the counter 12, and the counter 12 starts counting from the output of the second control circuit 5, The value is output to the second control circuit 5. A correction coefficient for each chromaticity change over time is obtained from the output value. (Here, the count value is counted.)
countR = fr (count)
countG = fg (count)
countB = fb (count)
The correction coefficient is multiplied by ROUT1, GOUT1, and BOUT1 set so as to compensate for the optical rotation dispersion of the liquid crystal panel 11.

ＲＯＵＴ＝ｃｏｕｎｔＲ・ＲＯＵＴ１
ＧＯＵＴ＝ｃｏｕｎｔＧ・ＧＯＵＴ１
ＢＯＵＴ＝ｃｏｕｎｔＢ・ＢＯＵＴ１
このようにして出力６、７、８にそれぞれ得られたＲＯＵＴ、ＧＯＵＴ、ＢＯＵＴは信号電極駆動回路９に入力される。言い換えると、入力の輝度レベルと電源起動時からの時間に応じてＲ、Ｇ、Ｂ信号にはそれぞれ他の信号成分が加わり、表示される画面の色度点が移動する。従って、上記マトリクス成分である係数ａ１１、ａ１２、…、ａ３３を液晶パネル１１の波長―透過率特性を補正するように設定すれば旋光分散と電源起動時からの色度ずれを補償することができる。 ROUT = countR · ROUT1
GOUT = countG · GOUT1
BOUT = countB · BOUT1
The ROUT, GOUT, and BOUT obtained in this way for the outputs 6, 7, and 8 are input to the signal electrode drive circuit 9. In other words, other signal components are added to the R, G, and B signals in accordance with the input luminance level and the time from the start of power supply, and the chromaticity point of the displayed screen moves. Accordingly, if the coefficients a11, a12,..., A33, which are the matrix components, are set so as to correct the wavelength-transmittance characteristics of the liquid crystal panel 11, it is possible to compensate for the optical rotation dispersion and the chromaticity deviation from the time of power activation. .

本発明にかかる液晶表示装置は、液晶表示装置が起動してからの時間によって生じる色度ずれを起動からの時間を記憶するカウンター値を元に前記マトリクス回路による各色信号成分処理の成分比を補正することによって正確な色再現をおこなう液晶表示装置を提供することが可能になるものであり、ＰＣ、ワープロなどのＯＡ機器やテレビなどのディスプレイとして用いられる液晶表示装置等において有用である。 The liquid crystal display device according to the present invention corrects the component ratio of each color signal component processing by the matrix circuit based on the counter value storing the time from the start of the chromaticity shift caused by the time after the start of the liquid crystal display device. This makes it possible to provide a liquid crystal display device that performs accurate color reproduction, and is useful in liquid crystal display devices that are used as displays for OA devices such as PCs and word processors, and televisions.

本発明の実施の形態１における液晶表示装置の全体構成図1 is an overall configuration diagram of a liquid crystal display device according to Embodiment 1 of the present invention. 従来の液晶表示装置の全体構成図Overall configuration diagram of a conventional liquid crystal display device

Explanation of symbols

１、２、３入力端子
４マトリクス回路
５第２の制御回路
６、７，８出力端子
９信号電極駆動回路
１０走査電極駆動回路
１１液晶パネル
１２カウンター
１３第１の制御回路 1, 2, 3 Input terminal 4 Matrix circuit 5 Second control circuit 6, 7, 8 Output terminal 9 Signal electrode drive circuit 10 Scan electrode drive circuit 11 Liquid crystal panel 12 Counter 13 First control circuit

Claims

The liquid crystal display device includes at least a counter for measuring a time after the liquid crystal display device is activated, and a matrix circuit for correcting a color signal component ratio using the counter output, and performs color reproduction at the time of activation. A liquid crystal display device characterized by the above.

A first control circuit to which each color signal component of the video signal is input; a matrix circuit for inputting each color signal component and multiplying each color signal component value by a coefficient and outputting the sum; and an output of the matrix circuit A liquid crystal driving circuit driven by the liquid crystal driving circuit and a liquid crystal panel driven by the liquid crystal driving circuit, a counter for measuring time from the time of power activation, and power activation of the first control circuit. 2. A liquid crystal display device comprising: a second control circuit which outputs to the counter and changes a component ratio of each color signal component processing of the matrix circuit in accordance with a value counted by the counter.