JPH07270752A - Data imprinting device for camera - Google Patents
Data imprinting device for cameraInfo
- Publication number
- JPH07270752A JPH07270752A JP5293495A JP5293495A JPH07270752A JP H07270752 A JPH07270752 A JP H07270752A JP 5293495 A JP5293495 A JP 5293495A JP 5293495 A JP5293495 A JP 5293495A JP H07270752 A JPH07270752 A JP H07270752A
- Authority
- JP
- Japan
- Prior art keywords
- liquid crystal
- crystal element
- voltage
- driving
- temperature
- 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
Landscapes
- Liquid Crystal (AREA)
- Camera Data Copying Or Recording (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はカメラ用データ写し込み
装置に関し、特にそのデータ写し込み用液晶素子の駆動
回路に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data imprinting apparatus for a camera, and more particularly to a driving circuit for a liquid crystal element for imprinting the data.
【０００２】[0002]
【従来の技術】従来のカメラ用データ写し込み装置は、
特開昭６０−５５３２２号公報の図１に記載されている
ように、写し込みデータを外部からユーザーが確認でき
る外部表示用液晶表示体１３をダイナミック（時分割）
駆動している。一方、カメラに内蔵され、ランプ１０か
らの光に対し液晶シャッターの役割をし、フィルムにデ
ータを写し込むデータ写し込み用液晶素子１２をスタテ
ィック駆動している。2. Description of the Related Art A conventional data imprinting device for a camera is
As shown in FIG. 1 of Japanese Unexamined Patent Publication No. 60-55322, a liquid crystal display 13 for external display, which allows a user to confirm the imprinted data from outside, is dynamic (time division).
It is driving. On the other hand, the data imprinting liquid crystal element 12 which is built in the camera and acts as a liquid crystal shutter for the light from the lamp 10 and imprints the data on the film is statically driven.
【０００３】[0003]
【発明が解決しようとする課題】上述の従来技術では、
データ写し込み用液晶素子１２がスタティック駆動され
ているため、セグメントの配線数が多くなり、写し込み
液晶パネルが大型になってしまうという課題を有してい
た。In the above-mentioned prior art,
Since the data-imprinting liquid crystal element 12 is statically driven, there is a problem in that the number of wirings in the segment increases, and the imprinting liquid crystal panel becomes large.
【０００４】そこで、ダイナミック駆動回路を用いてデ
ータ写し込み用液晶素子をダイナミック駆動するわけで
あるが、単にダイナミック駆動回路を用いてデータ写し
込み用液晶素子を駆動するだけでは、コントラスト（液
晶の光透過性能）が低下し、写し込みデータの写し込み
品質が低下してしまうという課題を有していた。Therefore, the data imprinting liquid crystal element is dynamically driven by using the dynamic driving circuit. However, if the data imprinting liquid crystal element is simply driven by using the dynamic driving circuit, the contrast (light of liquid crystal However, there is a problem that the transmissive performance is deteriorated and the imprinting quality of the imprinted data is deteriorated.
【０００５】本発明は、上記課題に鑑み、セグメントの
配線数を少なくし、液晶パネルを小型化し、写し込み品
質を向上させたカメラ用データ写し込み装置を提供する
ことを目的とする。In view of the above problems, an object of the present invention is to provide a data imprinting device for a camera in which the number of wirings in a segment is reduced, a liquid crystal panel is downsized, and imprint quality is improved.
【０００６】[0006]
【課題を解決するための手段】本発明のカメラ用データ
写し込み装置は、光源と、該光源からの光を選択的に透
過し、フィルムにデータを写し込むデータ写し込み用液
晶素子と、コモン電極とセグメント電極とを介して前記
液晶素子に液晶素子駆動用電圧を印加し、前記液晶素子
をダイナミック駆動するダイナミック駆動手段と、を有
するカメラ用データ写し込み装置であって、前記光源と
前記駆動手段とに供給する電源電圧の変動に伴う前記液
晶素子の光透過性変動を防止するよう、前記駆動用電圧
を一定に保持する定電圧手段を有することを特徴とす
る。SUMMARY OF THE INVENTION A camera data imprinting apparatus according to the present invention includes a light source, a data imprinting liquid crystal element that selectively transmits light from the light source and imprints data on a film, and a common. A data imprinting device for a camera, comprising: a dynamic driving means for dynamically driving the liquid crystal element by applying a liquid crystal element driving voltage to the liquid crystal element via an electrode and a segment electrode. And a constant voltage means for holding the driving voltage constant so as to prevent a change in light transmittance of the liquid crystal element due to a change in power supply voltage supplied to the means.
【０００７】また、前記液晶素子周囲の温度変動に伴う
前記液晶素子の光透過性変動を防止するよう、前記駆動
用電圧を補正する温度補正手段を有することを特徴とす
る。Further, the present invention is characterized by further comprising temperature correction means for correcting the driving voltage so as to prevent a change in light transmissivity of the liquid crystal element due to a change in temperature around the liquid crystal element.
【０００８】[0008]
【作用】本発明の構成によれば、定電圧手段により液晶
素子を駆動する電圧を安定化し、温度補正手段により温
度変化時の表示品質低下を防ぐ。その結果、ダイナミッ
ク駆動の液晶素子を用いて安定した写し込み品質を得る
ことができる。According to the structure of the present invention, the voltage for driving the liquid crystal element is stabilized by the constant voltage means and the display quality is prevented from being deteriorated by the temperature correction means. As a result, stable image quality can be obtained by using the liquid crystal element of dynamic drive.
【０００９】[0009]
【実施例】図１は、本発明の実施例における回路図を示
す。1 is a circuit diagram of an embodiment of the present invention.
【００１０】液晶素子１は、コモン電極５とセグメント
電極６とからなる１／４マルチ駆動パネルである。液晶
素子１を介して、ランプ１３の発光は、液晶素子１の透
過状態のデータをフィルムに透過露光する。１／４マル
チ駆動する液晶駆動回路２は、コモン電極５を駆動する
コモンドライバー７とセグメント電極６を駆動するセグ
メントドライバー８とからなる。温度補正付定電圧回路
３は、温度補正手段と定電圧手段が一体化されている
（後記）。４は、電源用電池である。昇圧回路９は、温
度補正付定電圧回路３の出力電圧１５（Ｖ1）を昇圧
し、２倍昇圧の出力電圧１６（Ｖ2）、３倍昇圧の出力
電圧１７（Ｖ3）を作成する。Ｖ1、Ｖ2、Ｖ3は、コモン
ドライバー７と、セグメントドライバー８を介して液晶
素子１に印加駆動される駆動用電圧である。データＲＡ
Ｍ１０は、液晶素子に出力されるデータを記憶する。論
理回路１１は、必要な回路制御を行い、ランプドライバ
ー１２は、ランプ駆動用トランジスタ１４によりランプ
１３を発光させる。The liquid crystal element 1 is a 1/4 multi-drive panel consisting of a common electrode 5 and a segment electrode 6. The light emitted from the lamp 13 through the liquid crystal element 1 transmits and exposes the data of the transmission state of the liquid crystal element 1 on the film. The 1/4 multi-driving liquid crystal drive circuit 2 includes a common driver 7 that drives the common electrode 5 and a segment driver 8 that drives the segment electrode 6. The temperature correction constant voltage circuit 3 has a temperature correction means and a constant voltage means integrated (described later). Reference numeral 4 is a power supply battery. The booster circuit 9 boosts the output voltage 15 (V1) of the temperature-corrected constant voltage circuit 3 to create a double boosted output voltage 16 (V2) and a triple boosted output voltage 17 (V3). V1, V2, and V3 are driving voltages applied and driven to the liquid crystal element 1 via the common driver 7 and the segment driver 8. Data RA
M10 stores the data output to the liquid crystal element. The logic circuit 11 performs necessary circuit control, and the lamp driver 12 causes the lamp driving transistor 14 to cause the lamp 13 to emit light.
【００１１】ここで、温度補正付定電圧回路３は、液晶
素子１の駆動電圧を常に最適値になるようにコントロー
ルしている。Here, the temperature correction constant voltage circuit 3 controls the drive voltage of the liquid crystal element 1 so that it is always at an optimum value.
【００１２】具体的には、ランプ１３の発光時に大電流
（約１００ｍＡ）が流れ、瞬間的に電池４の電圧が低下
しても液晶駆動電圧（Ｖ1、Ｖ2、Ｖ3）を一定に保つよ
う補正している。Specifically, when the lamp 13 emits a large current (about 100 mA), the liquid crystal drive voltage (V1, V2, V3) is corrected to be constant even if the voltage of the battery 4 is momentarily lowered. is doing.
【００１３】さらに、低温時の液晶素子の光透過性（コ
ントラスト）の低下を補正するために、温度補正を負の
勾配（約−７ｍＶ／℃）に設定している。温度補正の方
法は、感温素子を利用する等任意に設計できる。本実施
例では、ＭＯＳＩＣの基準電圧で作るトランジスタのＶ
THP（Ｐチャネル）とＶTHN（Ｎチャネル）との温度特性
差を利用して、定電圧出力１５（Ｖ1）が温度勾配を有
するようにしている。その具体的回路は公知であるた
め、省略する。本実施例での最適電圧値は、常温でＶ1
＝1.7Ｖ、Ｖ2＝3.4Ｖ、Ｖ3＝5.1Ｖであるが、ダイナミ
ックデューティーや液晶の特性に合わせ、電圧値や温度
変化係数を設計すればよい。Further, in order to correct the decrease in the light transmittance (contrast) of the liquid crystal element at low temperature, the temperature correction is set to a negative gradient (about -7 mV / ° C). The temperature correction method can be arbitrarily designed such as using a temperature sensitive element. In this embodiment, the V of the transistor created by the MOSIC reference voltage
The constant voltage output 15 (V1) is made to have a temperature gradient by utilizing the temperature characteristic difference between THP (P channel) and VTHN (N channel). The specific circuit is well known and therefore omitted. The optimum voltage value in this embodiment is V1 at room temperature.
= 1.7V, V2 = 3.4V, V3 = 5.1V, but the voltage value and the temperature change coefficient may be designed according to the dynamic duty and the characteristics of the liquid crystal.
【００１４】ダイナミック駆動は、透過コントラストの
品質（デューティーが高いほど品質が悪い）と、画素の
必要量（デューティーが高いほど画素多い）とを鑑み、
１／４〜１／８マルチ駆動が適当であるが、今後液晶の
品質改善に伴い、よりハイデューティーが可能となる。Dynamic driving takes into consideration the quality of transmission contrast (the higher the duty, the worse the quality) and the required amount of pixels (the higher the duty, the more pixels).
1/4 to 1/8 multi-driving is suitable, but with the improvement of the quality of liquid crystal in the future, higher duty becomes possible.
【００１５】また、本実施例の光源は、ランプを示した
が、ＬＥＤ、ＥＬ等の発光素子であればよい。Although the light source of this embodiment is a lamp, it may be any light emitting element such as LED or EL.
【００１６】本実施例によれば、液晶素子をダイナミッ
ク駆動することにより、セグメント本数を増やさず、デ
ューティーに相当した画素を作ることができる（例え
ば、１／４マルチ駆動であれば４倍、１／８マルチ駆動
であれば８倍）。従来のスタティック駆動では、数字し
か駆動できず、時刻情報のみの写し込みしかできない
が、本実施例では、ドット文字・グラフィックの写し込
みが可能になる。例えば、記念写真の地名や人名、撮影
時の天気や条件等を写し込みでき、写真の記録価値を増
大させることができる。According to the present embodiment, by dynamically driving the liquid crystal element, it is possible to make a pixel corresponding to the duty without increasing the number of segments (for example, in the case of 1/4 multi-driving, 4 times, 1 / 8 times for / 8 multi-drive). In the conventional static drive, only numbers can be driven and only time information can be imprinted, but in the present embodiment, dot characters / graphics can be imprinted. For example, the place name and person name of the commemorative photo, the weather and conditions at the time of shooting can be imprinted, and the recording value of the photo can be increased.
【００１７】また、画素を増やすのでなく、セグメント
数を減少させることもできる。その場合、ＩＣのパッド
の減少、基板パターン（セグメント）本数の減少、液晶
素子とのコネクタのピッチ余裕の増大、液晶素子パネル
の引出線（セグメント）の減少、等により、各々の部品
のサイズが小さくでき、装置を小型化でき、部品コスト
も安くすることができ、部品や実装の歩留まりが向上す
る。It is also possible to reduce the number of segments instead of increasing the number of pixels. In that case, the size of each component is reduced due to a decrease in the number of IC pads, a decrease in the number of substrate patterns (segments), an increase in the pitch margin of the connector with the liquid crystal element, and a decrease in the lead lines (segments) of the liquid crystal element panel. The size can be reduced, the device can be downsized, the cost of parts can be reduced, and the yield of parts and mounting can be improved.
【００１８】[0018]
【発明の効果】以上述べたように、本発明の構成によれ
ば、電源電圧変動に伴う液晶素子の光透過性変動を防止
するよう、液晶駆動用電圧を一定に保持する定電圧手段
を有するため、データ写し込み用液晶素子を駆動する液
晶駆動用電圧が安定化し急激な電源電圧の低下によるコ
ントラスト（液晶素子の光透過性）の低下を防止でき
る。As described above, according to the structure of the present invention, the constant voltage means for holding the liquid crystal driving voltage constant is provided so as to prevent the change in the light transmittance of the liquid crystal element due to the change in the power supply voltage. Therefore, the liquid crystal driving voltage for driving the data-imprinting liquid crystal element is stabilized, and it is possible to prevent a decrease in contrast (light transmittance of the liquid crystal element) due to a sudden decrease in the power supply voltage.
【００１９】従って、配線数の少ないダイナミック駆動
液晶素子を用いて高品位の写し込み品質を確保すること
ができるという効果を奏する。Therefore, there is an effect that a high quality imprinting quality can be secured by using a dynamic driving liquid crystal element having a small number of wirings.
【図１】本発明の実施例における回路ブロック図。FIG. 1 is a circuit block diagram according to an embodiment of the present invention.
１・・・・液晶素子 ２・・・・液晶駆動回路 ３・・・・温度補正付定電圧回路 ４・・・・電池 ５・・・・コモン電極 ６・・・・セグメント電極 １３・・・ランプ 1 ... Liquid crystal element 2 ... Liquid crystal driving circuit 3 ... Constant voltage circuit with temperature correction 4 ... Battery 5 ... Common electrode 6 ... Segment electrode 13 ... lamp
【手続補正書】[Procedure amendment]
【提出日】平成７年４月１０日[Submission date] April 10, 1995
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】特許請求の範囲[Name of item to be amended] Claims
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【特許請求の範囲】[Claims]
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００６[Correction target item name] 0006
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００６】[0006]
【課題を解決するための手段】本発明のカメラ用データ
写し込み装置は、光源と、該光源からの光を選択的に透
過し、フィルムにデータを写し込むデータ写し込み用液
晶素子と、コモン電極とセグメント電極とを介して前記
液晶素子に液晶素子駆動用電圧を印加し、前記液晶素子
をダイナミック駆動するダイナミック駆動手段と、を有
するカメラ用データ写し込み装置であって、前記液晶素
子周囲の温度変動に伴う前記液晶素子の光透過性変動を
防止するよう、前記駆動用電圧を補正する温度補正手段
を有することを特徴とする。SUMMARY OF THE INVENTION A camera data imprinting apparatus according to the present invention includes a light source, a data imprinting liquid crystal element that selectively transmits light from the light source and imprints data on a film, and a common. through the electrode and the segment electrode of the liquid crystal element driving voltage to the liquid crystal element, the liquid crystal element a device data imprinting camera has a dynamic drive means, the for dynamic driving, the liquid crystal element
The change in light transmittance of the liquid crystal element due to the temperature change around the child
Temperature correction means for correcting the drive voltage so as to prevent
It is characterized by having .
【手続補正３】[Procedure 3]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００７[Correction target item name] 0007
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００７】また、前記温度補正手段は、ＭＯＳＩＣの
ＰチャネルとＮチャネルとの温度特性を利用することを
特徴とする。Further, the temperature correction means is a MOSIC.
It is characterized in that the temperature characteristics of the P channel and the N channel are utilized .
【手続補正４】[Procedure amendment 4]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００８[Correction target item name] 0008
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００８】[0008]
【作用】本発明の構成によれば、温度補正手段により温
度変化時の表示品質低下を防ぐ。その結果、ダイナミッ
ク駆動の液晶素子を用いて安定した写し込み品質を得る
ことができる。According to the configuration of the present invention, prevent deterioration in display quality at the time of temperature change by temperature compensation means. As a result, stable image quality can be obtained by using the liquid crystal element of dynamic drive.
【手続補正５】[Procedure Amendment 5]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１８[Correction target item name] 0018
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１８】[0018]
【発明の効果】以上述べたように、本発明の構成によれ
ば、温度補正手段により温度変化時の表示品質低下を防
ぐことができるという効果を奏する。 As described above, according to the structure of the present invention, the display quality is prevented from being deteriorated by the temperature correction means.
It has the effect of being able to burn.
Claims (2)
写し込むデータ写し込み用液晶素子と、 コモン電極とセグメント電極とを介して前記液晶素子に
液晶素子駆動用電圧を印加し、前記液晶素子をダイナミ
ック駆動するダイナミック駆動手段と、を有するカメラ
用データ写し込み装置であって、 前記光源と前記駆動手段とに供給する電源電圧の変動に
伴う前記液晶素子の光透過性変動を防止するよう、前記
駆動用電圧を一定に保持する定電圧手段を有することを
特徴とするカメラ用データ写し込み装置。1. A light source, a data imprinting liquid crystal element that selectively transmits light from the light source and imprints data on a film, and a liquid crystal element drive to the liquid crystal element via a common electrode and a segment electrode. A data imprinting device for a camera, comprising: a dynamic driving means for applying a working voltage to dynamically drive the liquid crystal element, wherein the liquid crystal element of the liquid crystal element is accompanied by a change in a power supply voltage supplied to the light source and the driving means. A data imprinting device for a camera, comprising: a constant voltage means for holding the driving voltage constant so as to prevent a change in light transmittance.
晶素子の光透過性変動を防止するよう、前記駆動用電圧
を補正する温度補正手段を有することを特徴とする特許
請求の範囲第１項記載のカメラ用データ写し込み装置。2. The temperature compensating means for compensating the driving voltage so as to prevent the variation of the light transmissivity of the liquid crystal element due to the variation of the temperature around the liquid crystal element. A data imprinting device for a camera according to the item.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5293495A JPH07270752A (en) | 1995-03-13 | 1995-03-13 | Data imprinting device for camera |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5293495A JPH07270752A (en) | 1995-03-13 | 1995-03-13 | Data imprinting device for camera |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61034421A Division JP2579463B2 (en) | 1986-02-19 | 1986-02-19 | camera |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07270752A true JPH07270752A (en) | 1995-10-20 |
Family
ID=12928696
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5293495A Pending JPH07270752A (en) | 1995-03-13 | 1995-03-13 | Data imprinting device for camera |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07270752A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6731265B1 (en) | 1997-03-27 | 2004-05-04 | Sharp Kabushiki Kaisha | Display apparatus and method for driving the same |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5093160A (en) * | 1973-12-18 | 1975-07-25 | ||
| JPS5443762A (en) * | 1977-09-13 | 1979-04-06 | Seiko Epson Corp | Liquid crystal mechanism |
| JPS5633560A (en) * | 1979-08-24 | 1981-04-04 | Mitsubishi Electric Corp | Temperature compensation type detecting circuit for powor source voltage |
| JPS58202434A (en) * | 1982-05-20 | 1983-11-25 | Seiko Epson Corp | Data imprinting device of camera |
| JPS6067930A (en) * | 1983-09-22 | 1985-04-18 | Olympus Optical Co Ltd | Data imprinting device |
-
1995
- 1995-03-13 JP JP5293495A patent/JPH07270752A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5093160A (en) * | 1973-12-18 | 1975-07-25 | ||
| JPS5443762A (en) * | 1977-09-13 | 1979-04-06 | Seiko Epson Corp | Liquid crystal mechanism |
| JPS5633560A (en) * | 1979-08-24 | 1981-04-04 | Mitsubishi Electric Corp | Temperature compensation type detecting circuit for powor source voltage |
| JPS58202434A (en) * | 1982-05-20 | 1983-11-25 | Seiko Epson Corp | Data imprinting device of camera |
| JPS6067930A (en) * | 1983-09-22 | 1985-04-18 | Olympus Optical Co Ltd | Data imprinting device |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6731265B1 (en) | 1997-03-27 | 2004-05-04 | Sharp Kabushiki Kaisha | Display apparatus and method for driving the same |
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