JPH03288885A - Backlight brightness control circuit - Google Patents
Backlight brightness control circuitInfo
- Publication number
- JPH03288885A JPH03288885A JP2090645A JP9064590A JPH03288885A JP H03288885 A JPH03288885 A JP H03288885A JP 2090645 A JP2090645 A JP 2090645A JP 9064590 A JP9064590 A JP 9064590A JP H03288885 A JPH03288885 A JP H03288885A
- Authority
- JP
- Japan
- Prior art keywords
- backlight
- voltage
- circuit
- brightness
- comparators
- 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
- 238000001514 detection method Methods 0.000 claims description 4
- 238000005401 electroluminescence Methods 0.000 abstract 3
- 230000002093 peripheral effect Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
Landscapes
- Electroluminescent Light Sources (AREA)
- Circuit Arrangement For Electric Light Sources In General (AREA)
- Devices For Indicating Variable Information By Combining Individual Elements (AREA)
Abstract
Description
【発明の詳細な説明】
技術分野
本発明はバックライト明るさ制御回路に関し、特にハン
ディターミナル等に用いられるＥＬ（ＩＥＩｅｃｔｒｏ
ｌｕｖｌｎｅｓｃｃｎｃｅ ）バックライトの明るさ制
御回路に関する。DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a backlight brightness control circuit, and in particular to an EL (IEI electronic) circuit used in handheld terminals, etc.
luvlnesccnce) relates to a backlight brightness control circuit.
従来技術
従来、この種のＥＬバックライトにおいては、利用者の
マニュアル操作により点灯および消灯、あるいは明るさ
の調整が実施されていた。Prior Art Conventionally, in this type of EL backlight, the user manually operated to turn it on and off, or adjust the brightness.
このような従来のＥＬバックライトでは、利用者のマニ
ュアル操作により点灯および消灯が実施されていたので
、操作がわずられしいという欠点がある。Such conventional EL backlights have the disadvantage that they are difficult to operate because they are turned on and off by manual operations by the user.
また、その明るさの調整し利用者のマニュアルト”ｉ；
ｆｌにより実施され、一番明るい状態が明るい所でも
点灼していることが判るようにある捏度明るく設定され
ているため、周囲が暗くても一番明るい状態に設定され
た場合には必要以上に明るくなり、無駄な電力がｌｒ′
Ｉ費されるという欠点がある。In addition, the brightness can be adjusted using the user's manual.
It is implemented by fl, and the brightest state is set to a certain degree of brightness so that you can see that it is burning even in bright places, so it is necessary if it is set to the brightest state even if the surroundings are dark. The brightness becomes even brighter than that, and the wasted power is lr'
The disadvantage is that it costs a lot of money.
発明の目的
本発明は上記のような従来のものの欠点を除夫ずべくな
されたもので、自動的に点灯および泊灯を実施すること
ができ、消費電力を節減することができるバックライト
明るさ制御回路の択０ｔを［１的とする。Purpose of the Invention The present invention has been made to eliminate the drawbacks of the conventional ones as described above, and provides a backlight brightness that can automatically turn on and night lights and reduce power consumption. The selection 0t of the control circuit is assumed to be [1].
発明の構成
本発明によるバックライト明るさ制御回路は、バックラ
イト付き表示装置を有する端末装置のバックライト明る
さ制御回路であって、前記端末装置の周囲の明るさを検
出する検出手段と、前記検出手段の検出結果に応じて前
記バックライトへの供給電圧を可変するよう制御する制
御手段とを設けたことを特徴とする。Structure of the Invention A backlight brightness control circuit according to the present invention is a backlight brightness control circuit for a terminal device having a display device with a backlight, and includes a detection means for detecting the brightness around the terminal device; The present invention is characterized by further comprising a control means for controlling the voltage supplied to the backlight to be varied in accordance with the detection result of the detection means.
実施例
次に、本発明の一実施例について図面を参照して説明す
る。Embodiment Next, an embodiment of the present invention will be described with reference to the drawings.
第１図は本発明の一実施例の構成を示すプロ・ツク図で
ある。図において、光検出器１から出力された周囲光量
に相当する信号はアンプ２を介してコンパレータ３〜７
へ夫々人力される。FIG. 1 is a block diagram showing the configuration of one embodiment of the present invention. In the figure, a signal corresponding to the amount of ambient light output from a photodetector 1 is sent to comparators 3 to 7 via an amplifier 2.
Each is manually powered.
各コンパレータ３〜７の他方の人力には、基準電圧発生
回路８で発生された基準電圧ｖＯが抵抗ＲＯにより分圧
された電圧Ｖｌ−Ｖ４が夫々人力される。A voltage Vl-V4 obtained by dividing the reference voltage vO generated by the reference voltage generation circuit 8 by a resistor RO is applied to the other one of the comparators 3 to 7, respectively.
すなわち、コンパレータ３にはｖＯ、ランプくレータ４
にはＶｌ ［（４１５）ＶＯ］ ランプくレータ
５にはＶ２ ［（３１５）ＶＯ］ ランプくレータ
６１、：４；ｔＶ３ ［（２１５）ＶＯ］ ラン
プ＜レータ７にはＶ４ ［（１１５）ＶＯ］が夫々人
力されることになる。In other words, comparator 3 has vO, ramp collector 4
Vl [(415) VO] For lamp clutter 5, V2 [(315) VO] Ramp clutter 61, :4; tV3 [(215) VO] For lamp<lator 7, V4 [(115) VO] will be done manually.
各コンパレータ３〜７の出力Ｃ３〜Ｃ７はＥＬ（Ｅｌｅ
ｅｔｒｏｌｕｍｌｎｅｓｅｅｎｃｅ ）電圧発生回路９
の中でエンコードされ、ＥＬ電圧発生回路９からＥＬバ
ックライト１０の点灯電圧として出力される。ここで、
ＥＬバックライト１０は図示せぬＬＣＤ（液晶デイスプ
レィ）の裏側に設けられている。The outputs C3 to C7 of each comparator 3 to 7 are EL (Ele
) Voltage generation circuit 9
The voltage is encoded in the EL voltage generating circuit 9 and output as the lighting voltage of the EL backlight 10. here,
The EL backlight 10 is provided on the back side of an LCD (liquid crystal display) (not shown).
第２図は第１図のＥＬ電圧発生回路９の詳細な構成を示
すブロック図である。図において、コンパレータ４〜７
の出力Ｃ４〜Ｃ７は夫々抵抗Ｒを介してオペランプ１１
へ入力され、オペアンプ１］てコンパレータ４〜７の出
力Ｃ４〜Ｃ７が加算されることとなる。FIG. 2 is a block diagram showing a detailed configuration of the EL voltage generating circuit 9 of FIG. 1. In the figure, comparators 4 to 7
The outputs C4 to C7 are connected to the operational lamp 11 via resistors R, respectively.
and the outputs C4 to C7 of the comparators 4 to 7 are added to the operational amplifier 1].
また、コンパレータ３の出力Ｃ３はインノく一タ１２を
介してトランジスタＱ１のベースへ人力されるので、コ
ンパレータ３がオフの時にトランジスタＱｌはオンされ
、それによってトランジスタＱ２もオンされる。Further, since the output C3 of the comparator 3 is inputted to the base of the transistor Q1 via the inverter 12, the transistor Q1 is turned on when the comparator 3 is off, and thereby the transistor Q2 is also turned on.
トランジスタＱ２の出力は正弦波発生回路１３へ人力さ
れ、ＥＬ点灯信号として正弦波電圧がＥＬバックライト
１０に出力される。The output of the transistor Q2 is input to the sine wave generating circuit 13, and a sine wave voltage is outputted to the EL backlight 10 as an EL lighting signal.
この正弦波電圧は入力端子にしたがってその振幅が変更
されるので、ＥＬバックライト１０の明るさもこれにし
たがって変更される。Since the amplitude of this sine wave voltage is changed according to the input terminal, the brightness of the EL backlight 10 is also changed accordingly.
第３図は第１図のコンパレータ３〜７の入力端子とＥＬ
バックライト１０の明るさとの関係を示す図である。こ
の第３図を用いてＥＬ電圧発生回路９の入力端子と出力
電圧との関係を説明する。Figure 3 shows the input terminals of comparators 3 to 7 in Figure 1 and EL.
3 is a diagram showing a relationship with the brightness of a backlight 10. FIG. The relationship between the input terminal and output voltage of the EL voltage generation circuit 9 will be explained using FIG.
コンパレータ７だけがオンとなっているとき、すなわち
周囲が暗いときにはＥＬ電圧発生回路９の出力も低くな
り、コンパレータ６．５．４各々がオンになると、すな
わち周囲が明るくなるにつれて段階的にＥＬｒ＠圧発生
回路９の出力電圧が高くなる。When only the comparator 7 is turned on, that is, when the surroundings are dark, the output of the EL voltage generation circuit 9 is also low, and when each of the comparators 6, 5, and 4 is turned on, that is, as the surroundings become brighter, the ELr@ The output voltage of the pressure generating circuit 9 becomes higher.
さらに、コンパレータ３がオンになった場合には、周囲
が十分に明るくなってＥＬバックライト１０をつける必
要がないので、ＥＬ点灯電圧はオフされる。Further, when the comparator 3 is turned on, the EL lighting voltage is turned off because the surroundings are sufficiently bright and there is no need to turn on the EL backlight 10.
このように、光検出器１でターミナル（図示せず）の周
囲の明るさを検出し、この検出値に応じてＥＬ電圧発生
回路９によりＥＬ／＜−ツクライト１０のオン／オフお
よび明るさの調整を行うようにすることによって、自動
的にＥＬ／＜−ツクライト１０をオンオフすることがで
きる。In this way, the photodetector 1 detects the brightness around the terminal (not shown), and the EL voltage generating circuit 9 turns on/off the EL/<-trick light 10 and changes the brightness according to this detected value. By making the adjustment, the EL/<-turn light 10 can be automatically turned on and off.
また、周囲の明るさに対応じてＥＬバックライ］・］Ｏ
の明るさが制御されるので、周囲が暗いときにＥＬバッ
クライト１０を必要以上に明るくすることがなくなり、
消費電力を節減することができる。In addition, the EL backlight corresponds to the surrounding brightness]・]O
Since the brightness of the EL backlight 10 is controlled, the EL backlight 10 will not be made brighter than necessary when the surroundings are dark.
Power consumption can be reduced.
発明の詳細
な説明したように本発明によれば、検出された周囲の明
るさに応じてバックライトへの供給電圧をｉｉＪ変する
ようにすることによって、自動的に点対および消灯を実
施することができ、消費電力を節減することができると
いう効果がある。As described in detail, according to the present invention, the voltage supplied to the backlight is changed according to the detected ambient brightness, thereby automatically turning on and off the backlight. This has the effect of reducing power consumption.
第１図は本発明の一実施例の構成を示すプロ・ツク図、
第２図は第１図のＥＬ電圧発生回路の詳細な構成を示す
ブロック図、第３図は第１図のコンパレータの入力端子
とＥＬバックライトの明るさとの関係を示す図である。
主要部分の符号の説明
１・・・・・・光検出器
３〜７・・・・・・コンパレータ
８・・・・・・基準電圧発生回路
９・・・・・・ＥＬ電圧発生回路
１０・・・・・・ＥＬバックライトFIG. 1 is a program diagram showing the configuration of an embodiment of the present invention;
FIG. 2 is a block diagram showing the detailed configuration of the EL voltage generating circuit shown in FIG. 1, and FIG. 3 is a diagram showing the relationship between the input terminal of the comparator shown in FIG. 1 and the brightness of the EL backlight. Explanation of symbols of main parts 1... Photodetectors 3 to 7... Comparator 8... Reference voltage generation circuit 9... EL voltage generation circuit 10. ...EL backlight
Claims (1)
ックライト明るさ制御回路であって、前記端末装置の周
囲の明るさを検出する検出手段と、前記検出手段の検出
結果に応じて前記バックライトへの供給電圧を可変する
よう制御する制御手段とを設けたことを特徴とするバッ
クライト明るさ制御回路。(1) A backlight brightness control circuit for a terminal device having a display device with a backlight, the circuit comprising: a detection means for detecting the brightness around the terminal device; 1. A backlight brightness control circuit comprising: a control means for controlling a voltage supplied to the backlight to vary the voltage supplied to the backlight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2090645A JPH03288885A (en) | 1990-04-05 | 1990-04-05 | Backlight brightness control circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2090645A JPH03288885A (en) | 1990-04-05 | 1990-04-05 | Backlight brightness control circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03288885A true JPH03288885A (en) | 1991-12-19 |
Family
ID=14004246
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2090645A Pending JPH03288885A (en) | 1990-04-05 | 1990-04-05 | Backlight brightness control circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03288885A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5532854A (en) * | 1994-01-25 | 1996-07-02 | Fergason; James L. | Folded variable birefringerence zeroth order hybrid aligned liquid crystal apparatus |
| US5541745A (en) * | 1994-01-25 | 1996-07-30 | Fergason; James L. | Illumination system for a display using cholesteric liquid crystal reflectors |
| US5717422A (en) * | 1994-01-25 | 1998-02-10 | Fergason; James L. | Variable intensity high contrast passive display |
| EP1111575B1 (en) * | 1994-10-25 | 2008-08-20 | Fergason Patent Properties, LLC | Brightness control and halftoning in optical display system |
| US7843416B2 (en) | 1994-10-25 | 2010-11-30 | Fergason Patent Properties, Llc | Optical display system and method, active and passive dithering using birefringence, color image superpositioning and display enhancement with phase coordinated polarization switching |
| CN107393484A (en) * | 2014-07-04 | 2017-11-24 | 联想(北京)有限公司 | A kind of system control method and electronic equipment |
| US9847073B2 (en) | 2003-03-10 | 2017-12-19 | Fergason Licensing Llc | Apparatus and method for preparing, storing, transmitting and displaying images |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57154291A (en) * | 1981-03-18 | 1982-09-24 | Hitachi Ltd | Liquid crystal display unit |
| JPH03226716A (en) * | 1990-01-31 | 1991-10-07 | Mitsubishi Electric Corp | Display module |
-
1990
- 1990-04-05 JP JP2090645A patent/JPH03288885A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57154291A (en) * | 1981-03-18 | 1982-09-24 | Hitachi Ltd | Liquid crystal display unit |
| JPH03226716A (en) * | 1990-01-31 | 1991-10-07 | Mitsubishi Electric Corp | Display module |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5532854A (en) * | 1994-01-25 | 1996-07-02 | Fergason; James L. | Folded variable birefringerence zeroth order hybrid aligned liquid crystal apparatus |
| US5541745A (en) * | 1994-01-25 | 1996-07-30 | Fergason; James L. | Illumination system for a display using cholesteric liquid crystal reflectors |
| US5717422A (en) * | 1994-01-25 | 1998-02-10 | Fergason; James L. | Variable intensity high contrast passive display |
| EP1111575B1 (en) * | 1994-10-25 | 2008-08-20 | Fergason Patent Properties, LLC | Brightness control and halftoning in optical display system |
| US7843416B2 (en) | 1994-10-25 | 2010-11-30 | Fergason Patent Properties, Llc | Optical display system and method, active and passive dithering using birefringence, color image superpositioning and display enhancement with phase coordinated polarization switching |
| US7843417B2 (en) | 1994-10-25 | 2010-11-30 | Fergason Patent Properties, Llc | Optical display system and method, active and passive dithering using birefringence, color image superpositioning and display enhancement with phase coordinated polarization switching |
| US7843418B2 (en) | 1994-10-25 | 2010-11-30 | Fergason Patent Properties, Llc | Optical display system and method, active and passive dithering using birefringence, color image superpositioning and display enhancement with phase coordinated polarization switching |
| US9847073B2 (en) | 2003-03-10 | 2017-12-19 | Fergason Licensing Llc | Apparatus and method for preparing, storing, transmitting and displaying images |
| US9881588B2 (en) | 2003-03-10 | 2018-01-30 | Fergason Licensing Llc | Apparatus and method for preparing, storing, transmitting and displaying images |
| CN107393484A (en) * | 2014-07-04 | 2017-11-24 | 联想(北京)有限公司 | A kind of system control method and electronic equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8223117B2 (en) | Method and apparatus to control display brightness with ambient light correction | |
| JP3398734B2 (en) | Inverter circuit for driving LCD backlight | |
| JPH03288885A (en) | Backlight brightness control circuit | |
| US10650786B2 (en) | Automatically brightness adjusting electronic device and brightness adjusting method thereof | |
| JP2004281922A (en) | Current control device of light emitting element | |
| TW201507548A (en) | Illumination device | |
| JPH0764499A (en) | Display board | |
| JPH04230734A (en) | Arrangement of fluorescent lamp control circuit | |
| JP2623710B2 (en) | Liquid crystal display | |
| JPH0627440A (en) | Liquid crystal display device | |
| JPH06282231A (en) | Back light adjusting device for display panel | |
| JP3752333B2 (en) | Mobile device | |
| CN217591158U (en) | Circuit of radar type self-control lamp | |
| KR19980068470A (en) | Backlight of energy-saving LCD | |
| US7872431B2 (en) | Digital controlled multi-light driving apparatus | |
| KR100416708B1 (en) | Display light modulating apparatus | |
| JPH0536487A (en) | Fluorescent tube lighting apparatus | |
| JPH02309316A (en) | Liquid crystal display device | |
| JPS63311230A (en) | Liquid crystal display device | |
| JP2519914B2 (en) | camera | |
| TW200923637A (en) | Power-saving handset | |
| JP2920944B2 (en) | Lighting equipment | |
| JPH05127602A (en) | Illuminator | |
| JPH03266883A (en) | Portable electric appliance | |
| JPS604157Y2 (en) | Dial lighting device for electrical equipment with light emitting element clock |