JPS60107373A - Driving method of array-like light source - Google Patents
Driving method of array-like light sourceInfo
- Publication number
- JPS60107373A JPS60107373A JP58217506A JP21750683A JPS60107373A JP S60107373 A JPS60107373 A JP S60107373A JP 58217506 A JP58217506 A JP 58217506A JP 21750683 A JP21750683 A JP 21750683A JP S60107373 A JPS60107373 A JP S60107373A
- Authority
- JP
- Japan
- Prior art keywords
- light source
- array
- light
- sampling
- led
- 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
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/435—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material
- B41J2/447—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material using arrays of radiation sources
- B41J2/45—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of radiation to a printing material or impression-transfer material using arrays of radiation sources using light-emitting diode [LED] or laser arrays
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
- G06K15/00—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers
- G06K15/02—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers
- G06K15/12—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers
- G06K15/1238—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers simultaneously exposing more than one point
- G06K15/1242—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers simultaneously exposing more than one point on one main scanning line
- G06K15/1247—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by photographic printing, e.g. by laser printers simultaneously exposing more than one point on one main scanning line using an array of light sources, e.g. a linear array
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Optics & Photonics (AREA)
- General Engineering & Computer Science (AREA)
- Toxicology (AREA)
- General Health & Medical Sciences (AREA)
- Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Exposure Or Original Feeding In Electrophotography (AREA)
- Facsimile Heads (AREA)
- Dot-Matrix Printers And Others (AREA)
- Printers Or Recording Devices Using Electromagnetic And Radiation Means (AREA)
Abstract
Description
【発明の詳細な説明】
技術分野
本発明は、アレイ状光源を用いて電子写真プロセスによ
り感光体上に画像を形成する光プリンタにおけるアレイ
状光源駆動方法に関する。DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for driving an array light source in an optical printer that uses an array light source to form an image on a photoreceptor by an electrophotographic process.
従来技術
まず、第１図はアレイ状光源としてＬＥＤアレイを用い
た光プリンタの概要を示すもの、感光体ドラム１表面を
帯電チャージャ２により一様帯電した後、ＬＥＤアレイ
と結像素子を組込んだ光書込みヘッド３における各ＬＥ
ＤＩ％子の０Ｎ−ＯＦＦによる光スイッチングで感光体
ドラム１上に静電潜像を形成する。その後、現像ユニッ
ト４により潜像を顕像化し、給紙ローラ５によって給紙
された転写紙６上に転写チャージャ７により転写する。Prior Art First, Fig. 1 shows an outline of an optical printer using an LED array as an array light source.After the surface of a photoreceptor drum 1 is uniformly charged by a charger 2, an LED array and an imaging element are assembled. Each LE in the optical write head 3
An electrostatic latent image is formed on the photosensitive drum 1 by optical switching by turning DI% ON-OFF. Thereafter, the latent image is visualized by the developing unit 4 and transferred by the transfer charger 7 onto the transfer paper 6 fed by the paper feed roller 5.
転写後、転写紙６は搬送ベルト８により定着ユニット９
に送られて定着され、排紙ローラ１０により排紙される
。一方、感光体ドラム１はクリ−ニングユニット１１に
より表面がクリーニングされ次の作像に備える。After the transfer, the transfer paper 6 is transferred to the fixing unit 9 by the conveyor belt 8.
The paper is sent to the printer, where it is fixed, and then the paper is ejected by the paper ejection roller 10. On the other hand, the surface of the photosensitive drum 1 is cleaned by a cleaning unit 11 in preparation for the next image formation.
ここで、光書込みヘッド３は第２図及び第３図に示すよ
うに、ＬＥＤアレイヘッド１２と結像素子１例えばセル
フォックレンズ！３（商品名）とからなり、ＬＥＤアレ
イヘッド１２は放熱板１４上にセラミック基板１５を貼
付け、このセラミック基板１５の中央にＬＥＤアレイチ
ップを並べてＬＥＤアレイ光源１６とする方式が一般的
である。Here, as shown in FIGS. 2 and 3, the optical writing head 3 includes an LED array head 12 and an imaging element 1 such as a SELFOC lens! 3 (product name), and the LED array head 12 generally has a ceramic substrate 15 pasted on a heat sink 14, and LED array chips are arranged in the center of the ceramic substrate 15 to form an LED array light source 16.
ここに、ＬＥＤアレイの発光出力特性をみると。Here is a look at the light emitting output characteristics of the LED array.
第４図に示すように、周囲温度によってかなり変化する
環境温度特性がある。又、同じ条件で点灯させたとして
も、第５図に示すような経時特性があり、経時劣化する
。このような要因によりＬＥＤアレイの発光レベルが変
化すると、感光体上で安定した光量が得られず、印字品
質が低下してしまうことになる。As shown in FIG. 4, there are environmental temperature characteristics that vary considerably depending on the ambient temperature. Further, even if the lamp is turned on under the same conditions, there is a characteristic over time as shown in FIG. 5, and the lamp deteriorates over time. If the light emission level of the LED array changes due to such factors, a stable amount of light cannot be obtained on the photoreceptor, resulting in a decrease in print quality.
目的
本発明は、このような点に鑑みなされたもので、周囲温
度の変化、経時劣化等があっても、常に感光体上に安定
光量を確保でき、印字品質を向上させ得るアレイ状光源
駆動方法を提供することを目的とする。Purpose The present invention was made in view of the above points, and provides an array light source drive that can always secure a stable amount of light on a photoreceptor and improve printing quality even when there are changes in ambient temperature, deterioration over time, etc. The purpose is to provide a method.
構成
本発明の一実施例を第６図ないし第９図に基づいて説明
する。第１図ないし第３図で示した部分と同一部分は同
一符号を用い説明も省略する。まず、構造的には画像書
込みを行なうＬＥＤアレイ光源１６の一端にサンプリン
グ用ＬＥＤアレイ１７が設けら九ている。即ち、第７図
に示すように画像領域Ｅ、書込み幅Ｗｏ、画像有効幅Ｗ
１．書込み長Ｌｏ、画像有効長Ｌ１としたとき、Ｌ Ｅ
Ｄアレイ光源１６の長さはＷｏに対応するものであり
、サンプリング用ＬＥＤアレイ光源１７はその範囲外に
て感光体ドラムｌに対応している（セルフォックレンズ
１３もこれに対応する）。このようなサンプリング用Ｌ
ＥＤアレイ光源１７に対応させて感光体ドラム１上には
光量を検知する光センサ−１８が設けられている。ここ
で、ＬＥＤ発光光量を検知する光センサ−１８は増幅回
路イ１きのもので、センサー出力は積分回路１９に入力
されている（なお、光センサ−１８が増幅回路を有して
いない場合には、光センサ−１８・積分回路１９間に増
幅回路が付加される）。この積分回路１９の出力はサン
プリング信号に合わせてサンプルホールドするサンプル
ホールド回路２０に入力されている。そして、サンプル
ホールド回路２０の出力に応じてゲインが変化する可変
ゲイン増幅器２１が設けられている。さらに、この可変
ゲイン増幅器２１の出力により入力レベルが設定される
ＶＬＥＤ制御回路２２が設けられている。このＶｔ、
Ｅ Ｄ制御回路２２は入力レベルに応じたＶＬＥＤを決
定してＬＥＤ点灯回路２３に与えて、ＬＥＤの通電電流
を制御するものである。２４はＬＥＤ制御回路である。Structure One embodiment of the present invention will be described based on FIGS. 6 to 9. Components that are the same as those shown in FIGS. 1 to 3 are designated by the same reference numerals, and description thereof will be omitted. First, in terms of structure, a sampling LED array 17 is provided at one end of an LED array light source 16 for writing an image. That is, as shown in FIG. 7, the image area E, the writing width Wo, and the effective image width W
1. When writing length Lo and image effective length L1, L E
The length of the D array light source 16 corresponds to Wo, and the sampling LED array light source 17 corresponds to the photosensitive drum l outside of that range (the selfoc lens 13 also corresponds to this). L for sampling like this
An optical sensor 18 is provided on the photosensitive drum 1 in correspondence with the ED array light source 17 to detect the amount of light. Here, the optical sensor 18 that detects the amount of light emitted by the LED is equipped with an amplifier circuit 1, and the sensor output is input to the integrating circuit 19 (in case the optical sensor 18 does not have an amplifier circuit) (In this case, an amplifier circuit is added between the optical sensor 18 and the integrating circuit 19.) The output of the integrating circuit 19 is input to a sample and hold circuit 20 that samples and holds it in accordance with the sampling signal. A variable gain amplifier 21 whose gain changes depending on the output of the sample and hold circuit 20 is provided. Furthermore, a VLED control circuit 22 whose input level is set by the output of the variable gain amplifier 21 is provided. This Vt,
The ED control circuit 22 determines the VLED according to the input level and supplies it to the LED lighting circuit 23 to control the current flowing through the LED. 24 is an LED control circuit.
このような構成において、今、ＬＥＤ点灯部分が白くな
るポジーポジプロセスであるとして、動（１ｉ制御を第
９図を参照して説明する。まず、プリント信号受付けに
より印字が開始されるが、第７閤１−叫＋！ ＋−食二
ス九□１匡、ｌ旨芸の聞Ｌｍ 雨橡婁１人み４ｐ＋ 暑
が与えられることになる。ここで、この画像書込み信号
が与えられる前にサンプリング信号が与えられるもので
あり、このサンプリング信号が■］レベルの間、サンプ
リング用ＬＥＤアレイ光源１７がＬ Ｅ Ｄ’アレイ光
源１６と同一条件で点灯する。In such a configuration, the dynamic (1i control) will be explained with reference to FIG. 9, assuming that it is a positive process in which the LED lighting part becomes white. First, printing is started by receiving a print signal, but the 7 閤1-Scream +! +-Food 2 Su 9 □ 1 Kang, Lm Lm Rainy Day 1 person 4p+ Heat will be given.Here, before this image writing signal is given. A sampling signal is given, and while this sampling signal is at the [■] level, the sampling LED array light source 17 lights up under the same conditions as the LED array light source 16.
これにより、光センサ−１８は感光体ドラム１上におい
て発光光量を検知することになり、第８図に示す回路図
によりこのセンサー出力に応じてＬＥＤの印加電圧・が
制御され、発光光量が所定値になるように調光される。As a result, the optical sensor 18 detects the amount of emitted light on the photoreceptor drum 1, and the voltage applied to the LED is controlled according to the sensor output according to the circuit diagram shown in FIG. The light is dimmed to match the value.
このサンプリングに基づく点灯条件は次のサンプリング
信号が入力されるまでロックされる。しかして、画像書
込み信号によりＬＥＤアレイ光源１６の各ＬＥＤがＯＮ
・ＯＦ Ｆ’ して書込みを行なうことになるが、この
時のＬＥＤの点灯条件はサンプリングにより決定されて
おり、周囲温度の変化により発光光量が変わってしまう
ことはない。これは、セルフォックレンズ１３の汚れに
より感光体ドラム１で光量低下があっても補償されるこ
とになる。ところで、サンプリング用ＬＥＤアレイ光源
１７はサンプリング時間ｔの間だけでなく、書込み長信
号がＬレベルになるまで、ＬＥＤアレイ光源１６と同一
条件（ロックされた点灯条件）で点灯し続ける。その後
、消灯して、次のプリント信号から同様の制御が繰返さ
れる。ここで、書込み信号がＨレベルの間、サンプリン
グ用ＬＥＤアレイ光源１７が点灯し続けるのは、通常の
印字内容を見た場合画像の殆んどは白部分であり、ＬＥ
Ｄアレイ光源１６のＬＥＤが点灯していることが多く、
サンプリング用ＬＥＤアレイ光源１７も点灯させて経時
劣化状態をサンプリングして、経時劣化による光量低下
をカバーするためである。The lighting conditions based on this sampling are locked until the next sampling signal is input. Therefore, each LED of the LED array light source 16 is turned on by the image writing signal.
・Writing is performed with the LED turned OFF', but the lighting conditions of the LED at this time are determined by sampling, and the amount of emitted light does not change due to changes in ambient temperature. This compensates for a decrease in the amount of light on the photosensitive drum 1 due to dirt on the SELFOC lens 13. Incidentally, the sampling LED array light source 17 continues to be lit under the same conditions as the LED array light source 16 (locked lighting condition) not only during the sampling time t but also until the write length signal becomes L level. Thereafter, the light is turned off and the same control is repeated from the next print signal. Here, the reason why the sampling LED array light source 17 continues to light up while the write signal is at H level is that when looking at the normal printed content, most of the image is white, and the LED
The LED of the D array light source 16 is often lit,
This is to cover the reduction in light amount due to aging by turning on the sampling LED array light source 17 and sampling the state of aging.
ここで、ＬＥＤの調光方式としては、ＬＥＤに接続する
抵抗を可変にすることにより通電電流を制御する方式も
あるが、可変抵抗の数が非常に多くなるため、設計上好
ましくない。この点、本実施例のように印加電圧ＶＬＥ
Ｄを可変させてＬＥＤの通電電流を制御する方式によれ
ば、この印加電圧ＶＬＥＤは全てのＬＥＤに共通であり
、制御が簡単となる。Here, as an LED dimming method, there is a method in which the current is controlled by making the resistor connected to the LED variable, but this is not preferable in terms of design because the number of variable resistors becomes very large. In this respect, as in this embodiment, the applied voltage VLE
According to the method of controlling the current flowing through the LED by varying D, this applied voltage VLED is common to all LEDs, and control becomes simple.
ところで、ＬＥＤを点灯させた部分が黒くなるネガ−ポ
ジプロセスにおいても、第９図に示すタイミングチャー
トの如く行なわれるが、ポジーポジプロセスの場合と異
なり、サンプリング用ＬＥＤアレイ光源１７はサンプリ
ング時間ｔの間のみ点灯してその後消灯する（第９図（
ｄ）の破線参照）。これは、ポジーポジプロセスで説明
したように、印字に際して実際の画像（黒部分）の占め
る割合はきわめて少なく、ネガ−ポジプロセスでは画像
書込み信号入力中にＬＥＤアレイ光源１６においては点
灯するＬＥＤが少ないため、サンプリング用ＬＥＤアレ
イ光源１７も同様の使用状態として経時劣化をサンプリ
ングするためである。Incidentally, even in the negative-positive process in which the part where the LED is turned on is black, the timing chart shown in FIG. 9 is carried out, but unlike the positive-positive process, the sampling LED array light source 17 is It lights up only for a while and then turns off (Fig. 9 (
(See dashed line in d)). This is because, as explained in the positive-positive process, the proportion of the actual image (black area) during printing is extremely small, and in the negative-positive process, fewer LEDs are lit in the LED array light source 16 during input of the image writing signal. Therefore, the sampling LED array light source 17 is also used to sample deterioration over time as a similar usage condition.
なお、光量検知としては、第１０図に示すように感光体
ドラムｌ上に配置した光ファイバ２５によりセンサー１
８に伝送させて行なってもよい。The amount of light is detected by the sensor 1 using an optical fiber 25 placed on the photoreceptor drum l as shown in FIG.
8 may be transmitted.
又、アレイ状光源としてはＬＥＤアレイ光源１６に限る
ことなく螢光管アレイ光源等であってもよい。Further, the array light source is not limited to the LED array light source 16, but may be a fluorescent tube array light source or the like.
効果
本発明は、上述したように感光体上の光量を検知してア
レイ状光源を１調光させたので、周囲温度の変化や経時
劣化等があってもそれに応じて調光され、感光体上での
書込み光量を安定させることができ、よって、印字品質
の向上を図ることができるものである。Effects As described above, the present invention detects the amount of light on the photoconductor and dims the array light source by 1. Therefore, even if there is a change in ambient temperature or deterioration over time, the light is dimmed accordingly, and the light intensity on the photoconductor is adjusted. This makes it possible to stabilize the amount of writing light on the top, thereby improving printing quality.
第１図はプリンタの概略側面図、第２図はその光書込み
ヘッドの正面図、第３図は側面図、第４図は周囲温度−
発光出力の特性図、第５図は点灯時間−発光出力の特性
図、第６図は本発明の一実施例を示す正面図、第７図は
平面図、第８図はブロック図、第９図はタイミングチャ
ート、第１０図は変形例を示す正面図である。
ｌ・・感光体ドラム（感光体）、１６・・・ＬＥＤアレ
イ光源（アレイ光源）、１７・・・サンプリング用光源
、２３・・ＬＥＤ点灯回路
ｌｕ図 ３５図
３３６ 図Fig. 1 is a schematic side view of the printer, Fig. 2 is a front view of its optical writing head, Fig. 3 is a side view, and Fig. 4 is a schematic side view of the printer.
5 is a characteristic diagram of lighting time vs. luminous output, FIG. 6 is a front view showing an embodiment of the present invention, FIG. 7 is a plan view, FIG. 8 is a block diagram, and FIG. 9 is a characteristic diagram of light emission output. The figure is a timing chart, and FIG. 10 is a front view showing a modification. l... Photoconductor drum (photoconductor), 16... LED array light source (array light source), 17... Light source for sampling, 23... LED lighting circuit lu diagram 35 Figure 336 Figure
Claims (1)
体上に画像を形成する光プリンタにおいて、感光体上の
光量を検知して前記アレイ状光源を調光させるとと髪特
徴とするアレイ状光源駆動方法。 ２、サンプリング用光源を画像書込み用アレイ状光源と
独立させて設け、このサンプリング用光源を画像書込み
用アレイ状光源と同一条件で駆動させて感光体上の光量
を検知することを特徴とする特許請求の範囲第１項記載
のアレイ状光源駆動方法。 ３、感光体上の光量検知を感光体上にデータ書込みをし
ていないときにサンプリングして行なうことを特徴とす
る特許請求の範囲第１項記載のプレイ状光源駆動方法。 ４、光量検知に基づきアレイ状光源点灯回路への印加電
圧を制御してアレイ状光源を調光することを特徴とする
特許請求の範囲第１項記載のアレイ状光源駆動方法。1.7 In an optical printer that forms an image on a photoreceptor by an electrophotographic process using a array light source, the array light source is dimmed by detecting the amount of light on the photoreceptor. Light source driving method. 2. A patent characterized in that a sampling light source is provided independently of an image writing array light source, and the sampling light source is driven under the same conditions as the image writing array light source to detect the amount of light on the photoreceptor. A method for driving an array light source according to claim 1. 3. A method for driving a play-like light source according to claim 1, wherein the amount of light on the photoreceptor is detected by sampling when data is not being written on the photoreceptor. 4. The method for driving an array light source according to claim 1, wherein the array light source is dimmed by controlling the voltage applied to the array light source lighting circuit based on light intensity detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58217506A JPS60107373A (en) | 1983-11-17 | 1983-11-17 | Driving method of array-like light source |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58217506A JPS60107373A (en) | 1983-11-17 | 1983-11-17 | Driving method of array-like light source |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS60107373A true JPS60107373A (en) | 1985-06-12 |
Family
ID=16705298
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58217506A Pending JPS60107373A (en) | 1983-11-17 | 1983-11-17 | Driving method of array-like light source |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60107373A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6246464U (en) * | 1985-09-09 | 1987-03-20 | ||
| JPH01297269A (en) * | 1988-05-25 | 1989-11-30 | Matsushita Graphic Commun Syst Inc | Driving deterioration correction, and driving device of light emitting element array |
| US4929936A (en) * | 1988-03-21 | 1990-05-29 | Home Security Systems, Inc. | LED illuminated sign |
| JPH04308870A (en) * | 1991-04-05 | 1992-10-30 | Toray Ind Inc | Printer |
| US5235175A (en) * | 1989-07-25 | 1993-08-10 | Siemens Aktiengesellschaft | Arrangement for detecting the radiant energy of light-emitting semiconductor elements and its use in an electrophotographic printer |
| JPH0696294B2 (en) * | 1985-09-26 | 1994-11-30 | ジーメンス アクチエンゲゼルシヤフト | Electrophotographic printing apparatus having exposure energy correction device for optical character generator |
| EP1326199A3 (en) * | 2001-12-26 | 2004-06-02 | Xerox Corporation | Adaptive light emitting diode bar equalization |
| KR100830920B1 (en) | 2005-08-08 | 2008-05-22 | 세이코 엡슨 가부시키가이샤 | Light amount correcting method for light emitting apparatus, image forming apparatus, and display apparatus |
| US7728856B2 (en) | 2005-08-08 | 2010-06-01 | Seiko Epson Corporation | Light amount correcting method for light emitting apparatus, image forming apparatus, and display apparatus |
-
1983
- 1983-11-17 JP JP58217506A patent/JPS60107373A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6246464U (en) * | 1985-09-09 | 1987-03-20 | ||
| JPH0696294B2 (en) * | 1985-09-26 | 1994-11-30 | ジーメンス アクチエンゲゼルシヤフト | Electrophotographic printing apparatus having exposure energy correction device for optical character generator |
| US4929936A (en) * | 1988-03-21 | 1990-05-29 | Home Security Systems, Inc. | LED illuminated sign |
| JPH01297269A (en) * | 1988-05-25 | 1989-11-30 | Matsushita Graphic Commun Syst Inc | Driving deterioration correction, and driving device of light emitting element array |
| US5235175A (en) * | 1989-07-25 | 1993-08-10 | Siemens Aktiengesellschaft | Arrangement for detecting the radiant energy of light-emitting semiconductor elements and its use in an electrophotographic printer |
| JPH04308870A (en) * | 1991-04-05 | 1992-10-30 | Toray Ind Inc | Printer |
| EP1326199A3 (en) * | 2001-12-26 | 2004-06-02 | Xerox Corporation | Adaptive light emitting diode bar equalization |
| KR100830920B1 (en) | 2005-08-08 | 2008-05-22 | 세이코 엡슨 가부시키가이샤 | Light amount correcting method for light emitting apparatus, image forming apparatus, and display apparatus |
| US7728856B2 (en) | 2005-08-08 | 2010-06-01 | Seiko Epson Corporation | Light amount correcting method for light emitting apparatus, image forming apparatus, and display apparatus |
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