JPH0258980A - Brightness modulation circuit for image display device - Google Patents
Brightness modulation circuit for image display deviceInfo
- Publication number
- JPH0258980A JPH0258980A JP63210212A JP21021288A JPH0258980A JP H0258980 A JPH0258980 A JP H0258980A JP 63210212 A JP63210212 A JP 63210212A JP 21021288 A JP21021288 A JP 21021288A JP H0258980 A JPH0258980 A JP H0258980A
- Authority
- JP
- Japan
- Prior art keywords
- signal
- amplifier
- amplification degree
- cathode ray
- ray tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000003321 amplification Effects 0.000 claims abstract description 33
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 33
- 230000001360 synchronised effect Effects 0.000 claims description 6
- 230000002093 peripheral effect Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
Landscapes
- Picture Signal Circuits (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は、陰極線管を使用した映像表示装置の輝度変
調回路に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a brightness modulation circuit for a video display device using a cathode ray tube.
［従来技術］
第２図は従来の映像表示装置の輝度変調回路を示すブロ
ック図であり、図において、（１）は映像入力信号の信
号線、（２）は映像入力信号を増幅する増幅器、（３）
は増幅器（２）で増幅された映像出力信号の信号線、（
４）は信号線（３）を介して映像出力信号が供給される
陰極線管、（５）は増幅器（２）の増幅度を調整する増
幅度調整信号の信号線である。[Prior Art] FIG. 2 is a block diagram showing a brightness modulation circuit of a conventional video display device. In the figure, (1) is a signal line for a video input signal, (2) is an amplifier that amplifies the video input signal, (3)
is the signal line of the video output signal amplified by the amplifier (2), (
4) is a cathode ray tube to which a video output signal is supplied via a signal line (3), and (5) is a signal line for an amplification adjustment signal for adjusting the amplification degree of the amplifier (2).
次に動作について説明する。陰極線管（４）を用いた映
像表示装置では、信号線（１）を介して供給された映像
人力信号を増幅器（２）により増幅し、この増幅された
映像出力信号を信号線（３）を介して陰極線管（４）の
陰極（４ａ）に供給し、この映像出力信号で陰極（４ａ
）をドライブして陰極線管（４）の表示画面に映像を表
示する。Next, the operation will be explained. In a video display device using a cathode ray tube (4), a video signal supplied via a signal line (1) is amplified by an amplifier (2), and this amplified video output signal is sent to a signal line (3). The video output signal is supplied to the cathode (4a) of the cathode ray tube (4) through the video output signal.
) to display images on the display screen of the cathode ray tube (4).
この場合、上記増幅器（２）の増幅度は信号線（５）を
介して供給される増幅度調整信号で決定し、陰極線管（
４）の表示画面の輝度を調整している。上記増幅度調整
信号は無変調の直流が用いられている。In this case, the amplification degree of the amplifier (2) is determined by the amplification degree adjustment signal supplied via the signal line (5),
4) Adjusting the brightness of the display screen. An unmodulated direct current is used as the amplification degree adjustment signal.
［発明が解決しようとする課題］
従来の映像表示装置の輝度変調回路は以上のように構成
されているので、増幅器の増幅度は、外部調整を行わな
い限り一定である。ところが陰極線管の特性上、一定の
増幅度では表示画°面の中央部と周辺部の輝度が異なる
という問題点があった。[Problems to be Solved by the Invention] Since the brightness modulation circuit of the conventional video display device is configured as described above, the amplification degree of the amplifier is constant unless external adjustment is performed. However, due to the characteristics of cathode ray tubes, there is a problem in that, at a constant amplification level, the brightness at the center and the periphery of the display screen differs.
この発明は上記のような問題点を解消することを課題に
なされたもので、表示画面の中央部と周辺部の輝度を同
一にできる映像表示装置の輝度変調回路を得ることを目
的とする。The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a brightness modulation circuit for a video display device that can equalize the brightness of the central part and the peripheral part of a display screen.
〔課題を解決するための手段］
この発明に係る映像表示装置の輝度変調回路は、直流の
基本増幅度調整信号に陰極線管の水平及び垂直の走査周
期に同期したパラボラ状の変調信号を重畳させて、映像
入力信号を増幅する増幅器の増幅度調整信号としたもの
である。[Means for Solving the Problems] A brightness modulation circuit for a video display device according to the present invention superimposes a parabolic modulation signal synchronized with the horizontal and vertical scanning cycles of a cathode ray tube on a DC basic amplification adjustment signal. This is an amplification degree adjustment signal for an amplifier that amplifies a video input signal.
［作用］
この発明における増幅度調整信号は、直流の基本増幅度
調整信号に映像表示装置の水平及び垂直の走査周期に同
期したパラボラ状の変調信号を重畳させたことにより、
増幅器の増幅度を自動的に可変することができ、表示画
面の輝度を全面に渡り同じにする。[Function] The amplification degree adjustment signal in the present invention is obtained by superimposing a parabolic modulation signal synchronized with the horizontal and vertical scanning cycles of the video display device on the DC basic amplification degree adjustment signal.
The amplification degree of the amplifier can be automatically varied to make the brightness of the display screen the same over the entire surface.
［実施例］
以下、この発明の一実施例を図について説明する。前記
第２図と同一部分に同一符号を付した第１図において、
（６）は直流の基本増幅度調整信号を供給する信号線、
（７）は陰極線管（４）の水平及び垂直の走査周期に同
期したパラボラ状の変調信号を供給する信号線、（８）
は基本増幅度調整信号と変調信号を重畳する加算器、（
９）は加算器（８）から出力された増幅度調整信号を増
幅器（２）に供給する信号線である。[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. In Fig. 1, in which the same parts as in Fig. 2 are given the same reference numerals,
(6) is a signal line that supplies a DC basic amplification adjustment signal;
(7) is a signal line that supplies a parabolic modulation signal synchronized with the horizontal and vertical scanning cycles of the cathode ray tube (4); (8)
is an adder that superimposes the basic amplification adjustment signal and the modulation signal, (
9) is a signal line that supplies the amplification adjustment signal output from the adder (8) to the amplifier (2).
第２図は表示画面の全面に対する変調信号（１０）の特
性を示したもので、この変調信号（１０）は垂直走査周
期のパルス（１１）に同期してパラボラ状となっている
。FIG. 2 shows the characteristics of the modulation signal (10) over the entire surface of the display screen, and this modulation signal (10) has a parabolic shape in synchronization with the pulse (11) of the vertical scanning period.
第３図は第２図の時間軸を拡大した一区分の変調信号（
１０）の特性を示したもので、この変調信号（１０）は
水平の走査周期のパルス（１２）に同期してパラボラ状
となっている。Figure 3 shows one section of the modulated signal (
10), this modulation signal (10) has a parabolic shape in synchronization with the horizontal scanning period pulse (12).
なお、第２図、第３図において、（ｖｈ）は変調信号（
１０）の水平方向の特性幅、（Ｖｖ）は変調信号（１０
）の垂直方向の特性幅である。In addition, in FIGS. 2 and 3, (vh) is the modulation signal (
The horizontal characteristic width (Vv) of the modulation signal (10)
) is the characteristic width in the vertical direction.
次に上記実施例の動作について説明する。映像入力信号
は信号線（１）を介して増幅器（２）に供給され、この
増幅器（２）で増幅された映像出力信号は信号線（３）
を介して陰極線管（４）の陰極（４ａ）に供給される。Next, the operation of the above embodiment will be explained. The video input signal is supplied to the amplifier (2) via the signal line (1), and the video output signal amplified by this amplifier (2) is supplied to the signal line (3).
is supplied to the cathode (4a) of the cathode ray tube (4).
この場合、上記増幅器（２）に供給されている増幅度調
整信号は、第２図、第３図に示す陰極線管の水平の走査
周期のパルス（１２）及び垂直の走査周期のパルス（１
１）に同期したパラボラ状の変調信号（１０）を直流の
基本増幅度調整信号に重畳したものであり、増幅器（２
）の増幅度は表示画面の中央部では低く周辺部では高く
なる。In this case, the amplification adjustment signal supplied to the amplifier (2) is a pulse (12) in the horizontal scanning period of the cathode ray tube and a pulse (12) in the vertical scanning period of the cathode ray tube shown in FIGS.
The parabolic modulation signal (10) synchronized with 1) is superimposed on the DC basic amplification adjustment signal, and the amplifier (2)
) is low at the center of the display screen and high at the periphery.
その結果、表示画面は全面に渡り一定の輝度となる。As a result, the display screen has constant brightness over the entire surface.
また、パラボラ状の変調信号（１０）の水平方向の特性
幅ｖｈ及び垂直方向の特性幅Ｖｖを可変できるような回
路を用いれば、特性の異なる陰極線管についても同一の
結果が得られる。Further, by using a circuit that can vary the horizontal characteristic width vh and vertical characteristic width Vv of the parabolic modulation signal (10), the same result can be obtained even for cathode ray tubes with different characteristics.
［発明の効果］
以上のように、この発明によれば、直流の基本増幅度調
整信号と陰極線管の水平及び垂直の走査周期に同期した
パラボラ状の変調信号を重畳した増幅度調整信号で映像
入力信号を増幅する増幅きの増幅度を調整するように構
成したので、表示画面の全面を一定の輝度とすることが
でき、精度の高い汎用性のある画像表示が得られる効果
がある。[Effects of the Invention] As described above, according to the present invention, an image can be created using an amplification adjustment signal in which a DC basic amplification adjustment signal and a parabolic modulation signal synchronized with the horizontal and vertical scanning periods of a cathode ray tube are superimposed. Since the amplification degree of the amplification for amplifying the input signal is adjusted, the entire surface of the display screen can be kept at a constant brightness, which has the effect of providing highly accurate and versatile image display.
第１図はこの発明の一実施例による画像表示装置の輝度
変調回路を示すブロック図、第２図は表示画面の全面に
対する変調信号の特性図、第３図は第２図の時間軸を拡
大した一区分の変調信号の特性図、第４図は従来の映像
表示装置の輝度変調回路のブロック図である。
図において、（２）は映像入力信号の増幅器、（４）は
陰極線管、（６）は基本増幅度調整信号の信号線、（７
）はパラボラ状の変調信号の信号線、（８）は増幅度調
整信号の信号線、（１０）は変調信号である。
図中、同一符号は同一または相当部分を示す。Fig. 1 is a block diagram showing a brightness modulation circuit of an image display device according to an embodiment of the present invention, Fig. 2 is a characteristic diagram of a modulation signal over the entire display screen, and Fig. 3 is an enlarged view of the time axis of Fig. 2. FIG. 4 is a block diagram of a brightness modulation circuit of a conventional video display device. In the figure, (2) is the amplifier for the video input signal, (4) is the cathode ray tube, (6) is the signal line for the basic amplification level adjustment signal, and (7) is the signal line for the basic amplification adjustment signal.
) is a signal line for a parabolic modulation signal, (8) is a signal line for an amplification adjustment signal, and (10) is a modulation signal. In the drawings, the same reference numerals indicate the same or corresponding parts.
Claims (1)
直流の基本増幅度調整信号と前記陰極線管の水平及び垂
直の走査周期に同期したパラボラ状の変調信号を重畳し
て前記増幅器に増幅度調整信号を供給する加算器とを備
えたことを特徴とする映像表示装置の輝度変調回路。an amplifier that amplifies the video input signal and supplies it to the cathode ray tube;
It is characterized by comprising an adder that superimposes a DC basic amplification adjustment signal and a parabolic modulation signal synchronized with the horizontal and vertical scanning periods of the cathode ray tube and supplies the amplification adjustment signal to the amplifier. Brightness modulation circuit for video display devices.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63210212A JPH0258980A (en) | 1988-08-24 | 1988-08-24 | Brightness modulation circuit for image display device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63210212A JPH0258980A (en) | 1988-08-24 | 1988-08-24 | Brightness modulation circuit for image display device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0258980A true JPH0258980A (en) | 1990-02-28 |
Family
ID=16585645
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63210212A Pending JPH0258980A (en) | 1988-08-24 | 1988-08-24 | Brightness modulation circuit for image display device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0258980A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5519447A (en) * | 1993-10-28 | 1996-05-21 | Mitsubishi Denki Kabushiki Kaisha | Wide aspect television receiver including a correcting waveform signal generator |
| GB2317313A (en) * | 1996-09-13 | 1998-03-18 | Lg Electronics Inc | Uniform brightness system for CRT display |
-
1988
- 1988-08-24 JP JP63210212A patent/JPH0258980A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5519447A (en) * | 1993-10-28 | 1996-05-21 | Mitsubishi Denki Kabushiki Kaisha | Wide aspect television receiver including a correcting waveform signal generator |
| GB2317313A (en) * | 1996-09-13 | 1998-03-18 | Lg Electronics Inc | Uniform brightness system for CRT display |
| GB2317313B (en) * | 1996-09-13 | 1998-12-30 | Lg Electronics Inc | Brightness control apparatus for video display appliance |
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