JPS60123168A - Correcting method of shading - Google Patents

Correcting method of shading

Info

Publication number
JPS60123168A
JPS60123168A JP58231084A JP23108483A JPS60123168A JP S60123168 A JPS60123168 A JP S60123168A JP 58231084 A JP58231084 A JP 58231084A JP 23108483 A JP23108483 A JP 23108483A JP S60123168 A JPS60123168 A JP S60123168A
Authority
JP
Japan
Prior art keywords
signal
scanning
light beam
recording
correction
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.)
Granted
Application number
JP58231084A
Other languages
Japanese (ja)
Other versions
JPH0215153B2 (en
Inventor
Kunio Tomohisa
友久 国雄
潔 前田
長 正道
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dainippon Screen Manufacturing Co Ltd
Original Assignee
Dainippon Screen Manufacturing Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Dainippon Screen Manufacturing Co Ltd filed Critical Dainippon Screen Manufacturing Co Ltd
Priority to JP58231084A priority Critical patent/JPS60123168A/en
Priority to US06/671,984 priority patent/US4691241A/en
Priority to GB08430654A priority patent/GB2151876B/en
Priority to DE19843444581 priority patent/DE3444581A1/en
Publication of JPS60123168A publication Critical patent/JPS60123168A/en
Priority to GB08703957A priority patent/GB2185654B/en
Publication of JPH0215153B2 publication Critical patent/JPH0215153B2/ja
Granted legal-status Critical Current

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  • Facsimile Scanning Arrangements (AREA)
  • Facsimile Image Signal Circuits (AREA)

Abstract

PURPOSE:To correct shading easily by multiplying a picture signal at the scanning side or a record signal by a correction signal in correspondence to a change in a scanning speed of a scanning light beam or a recording light beam in real time. CONSTITUTION:An input picture signal VP obtained by scanning photoelectrically a reference base, for instance, a white color, is inputted to one terminal of an analogue multiplier 22a as a VPU through an amplifier 21. After it has been converted into a signal VLPF outputted from a low-pass filter 32 of a PLL circuit 3, it is inputted to the other terminal of the multiplier 22a. After the VPU has been multiplied by the VLPF in the multiplier 22a, a picture signal Vdata executed shading correction can be obtaind. Then the picture signal is inputted to an A/D conversion circuit 24 and a signal processing circuit 25 for gradation correction, etc.

Description

【発明の詳細な説明】 この発明は平面走査型画像走査記録装置での走査速度変
化にともなう走査光量又は記録光量の変化を補正するシ
ェーディング補正に関するものである。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to shading correction for correcting changes in the amount of scanning light or recording light due to changes in scanning speed in a plane scanning type image scanning recording apparatus.

平面走査型の画像走査記録装置で原画を光電走査する場
合には、例えば第1図に示す如き光学系を用いて行なわ
れる。第1図に於てレーザ発振器(lla)の出力光ビ
ームは、ハーフミラ、−等の光学素子により、後述する
グレーティングビームBGと走査光ビームBP iζ分
岐される。走査光ビームBPはビームエキスパンダ(1
2F)で所定のビーム径まで拡大されてガルバノミラ−
〇に入射され、該カルパノミラー(ト)で偏向された後
、対物レンズ0慢及び折返しミラーQf9を介して走査
面A上を図示矢印方向に走査する。そして走査面Aから
の反射光を受光センサアレイQOで光m変換する様にな
っている。
When an original image is photoelectrically scanned by a plane scanning type image scanning recording apparatus, an optical system as shown in FIG. 1 is used, for example. In FIG. 1, the output light beam of the laser oscillator (lla) is split into a grating beam BG and a scanning light beam BP iζ to be described later by an optical element such as a half mirror. The scanning light beam BP passes through a beam expander (1
2F), the beam is expanded to a predetermined beam diameter and a galvanomirror is applied.
The beam is incident on the point 〇, is deflected by the Carpano mirror (g), and then scans on the scanning plane A in the direction of the arrow shown in the figure via the objective lens 0 and the reflection mirror Qf9. Then, the reflected light from the scanning surface A is converted into light m by the light receiving sensor array QO.

尚第1図には後の説明中で述べるグレーティング信号f
inを得る光学系も同時に示されている。
In addition, FIG. 1 shows a grating signal f, which will be described later in the explanation.
An optical system for obtaining in is also shown at the same time.

すなわち前記グレーティングビームBGはエキスパンダ
(igo)で所定のビーム径まで拡大されてガルバノミ
ラ−(至)に入射され、該ガルバノミラーα場で偏向さ
れた後、対物レンズ04を介してグレーティングa″I
)に入射される。グレーティングα力の格子間隙を通過
したビームは受光センサアレイθ枠に入射され、該受光
センサアレイ(ト)からグレーティング信号finを得
る様になっている。
That is, the grating beam BG is expanded to a predetermined beam diameter by an expander (igo), is incident on a galvano mirror (to), is deflected by the α field of the galvano mirror, and then passes through an objective lens 04 to a grating a''I.
). The beam passing through the grating gap of the grating α force is incident on the light receiving sensor array θ frame, and a grating signal fin is obtained from the light receiving sensor array (g).

1記光学系の構成に於てガルバノミラ−(至)はV =
 V(I 5inetJ t −(1)vo:駆動信号
の最大振幅 ω :角速度 なる信号V(Volt)でモータ駆動される。従ってガ
ルバノミラ−〇葎の振れ角θ(rad )はθ=θ6 
Slnωt ・・・(2) θ0二ガルバノミラ−の最大振れ角(rad)で表わさ
れる。
In the configuration of the optical system mentioned above, the galvano mirror (to) is V =
V (I 5inetJ t - (1) vo: Maximum amplitude of the drive signal ω: The motor is driven by the signal V (Volt) which is the angular velocity. Therefore, the deflection angle θ (rad) of the galvanometer mirror is θ = θ6
Slnωt (2) θ0 is expressed as the maximum deflection angle (rad) of the two galvano mirrors.

第2図は上記ガルバノミラ−(ハ)で走査光ビームBr
が偏向され走査面A上を走査する状態を拡大して示した
ものでここでは、折返しミラー(ト)は省略されている
Figure 2 shows the scanning light beam Br by the galvanometer mirror (c).
This is an enlarged view of the state in which the beam is deflected and scanned on the scanning surface A, and the folding mirror (g) is omitted here.

同図中、走査光ビームBPの振り幅L (a+)は対物
レンズQΦの焦点距離をf (H>としたとき次の如く
になる。
In the figure, the amplitude L (a+) of the scanning light beam BP is as follows when the focal length of the objective lens QΦ is f (H>).

L=2・y≠2・f−−20 =2・f”jan(2[@・sinωt) −・−(3
)また該ビームBpの走査速度■は (ただし、kl=4・f・θ0・ω) となる。
L=2・y≠2・f−−20 =2・f”jan(2[@・sinωt) −・−(3
) Also, the scanning speed (2) of the beam Bp is (where kl=4·f·θ0·ω).

また、当該光学系においては、走査面Aにおける光ビー
ムのスポット径が一定であるため、該ビームBPが単位
民さlを通過する時間Tはで表わされる。
In addition, in this optical system, since the spot diameter of the light beam on the scanning surface A is constant, the time T for the beam BP to pass through the unit length l is expressed as.

従って走査向A上での走査光量Eは次式(6)で表わせ
る。
Therefore, the amount of scanning light E in the scanning direction A can be expressed by the following equation (6).

P: レーザービームのパワー(W) 上記(6)式で与えられる走査光M E CW’ se
a = J )を規格化した1例をグラフで示すと第8
図の如くになり、かかる光旭の走査光ビームBPにより
原画を走査して画像信号を得た場合該画像信号は中心部
が小さく周辺部が大きくなって正確な画像信号を得るこ
とはできない。そこで従来から走査光ビームの走査速度
の変化にともなう走査光量の変化を補正するため、シェ
ーディング補正が行なわれている。このシェーディング
補正の1例としては、例えば特11u昭58−2746
6に開示された如きものがあり、ここでは特定走査位置
に対応させたシェーディング補正係数を、あらかじめメ
モリ装置に記憶させておき、画像信号に対してシェーデ
ィング補正を行なう方法が開示されている。
P: Laser beam power (W) Scanning light M E CW' se given by equation (6) above
An example of normalizing a = J) is shown in the 8th graph.
As shown in the figure, when an image signal is obtained by scanning an original image with the scanning light beam BP of the light beam BP, the image signal is small at the center and large at the periphery, making it impossible to obtain an accurate image signal. Therefore, shading correction has been conventionally performed in order to correct changes in the amount of scanning light due to changes in the scanning speed of the scanning light beam. As an example of this shading correction, for example,
There is a method as disclosed in No. 6, in which a shading correction coefficient corresponding to a specific scanning position is stored in a memory device in advance, and shading correction is performed on an image signal.

しかしながらこの方法に於てはメモリ装置が必要である
こと、また上記メモリ装置の容量を小さくするために前
記特定走査位置以外の位置の補正係数は補間計算によっ
て得ているので該計算のための複雑な回路及び係数計算
のためのソフトウェアが必要となる欠点がある。また、
かかる係数計算には、回路の応答性に限定される計算速
度の限界があり、リアルタイムでの補正が困難であった
However, this method requires a memory device, and in order to reduce the capacity of the memory device, the correction coefficients for positions other than the specific scanning position are obtained by interpolation calculation, so the calculation is complicated. The disadvantage is that it requires a sophisticated circuit and software for coefficient calculation. Also,
Such coefficient calculation has a calculation speed limit that is limited by the responsiveness of the circuit, and it has been difficult to correct it in real time.

また、他の例としては、例えば特公昭58−19187
に開示された如きものがあり、ここでは前記例に於ける
如く、補正係数そのものをメモリ装置に記憶させるので
なく、該メモリ装置には補正係数の逆数を記憶しておき
、掛算によって入力信号に対してシェーディング補正を
する方法が開示されている。この場合、メモリ容量を減
少させるべく補正係数の逆数からある定数を引いた値を
メモリ装置に記憶させる様にしているが、前記例と同様
、メモリ装置が必要であり、演算回路が複雑であるので
高価となる難点がある。更に他の公知例として、例えば
特開昭57−119565があるが、ここでも補正値を
メモリ装置に記憶させておき、該補正値に基づいて入力
信号を補正する方法が示されている。この方法は前記2
つの公知例と同じくメモリ装置や演算回路を必要とする
という難点に加えて、予め基準面(白紙原稿)を光電走
査して上記補正値を作る必要があり、操作上の難点をも
伴っている。
In addition, as another example, for example, Special Publication No. 58-19187
Here, instead of storing the correction coefficient itself in the memory device as in the above example, the reciprocal of the correction coefficient is stored in the memory device, and the input signal is multiplied by the reciprocal of the correction coefficient. A method for performing shading correction is disclosed. In this case, in order to reduce the memory capacity, a value obtained by subtracting a certain constant from the reciprocal of the correction coefficient is stored in the memory device, but as in the previous example, a memory device is required and the calculation circuit is complicated. Therefore, it has the disadvantage of being expensive. Further, as another known example, there is, for example, Japanese Patent Laid-Open No. 119565/1983, which also discloses a method of storing correction values in a memory device and correcting an input signal based on the correction values. This method is described in 2.
In addition to the disadvantage of requiring a memory device and arithmetic circuit as with the other known examples, it is also necessary to photoelectrically scan a reference surface (blank original) to create the above correction value, which also poses operational difficulties. .

この発明は上記従来の事情に鑑みてなされたものであり
、その要点は画像走査記録装置によって得た画像信号又
は該画像信号に、所要の処理を施して得た記録信号に走
査光ビーム、又は記録光ビームの速度変化に対応する補
正信号を、リアルタイムで掛は合わせることにある。こ
こでは該補正信号としてグレーティング信号から導き出
される信号を用いており、従って回路的には上記掛は合
わせを行う乗算回路を設けるだけでよく回路の簡略化を
図ることができる。
This invention has been made in view of the above-mentioned conventional circumstances, and its main point is to apply a scanning light beam or The purpose of this method is to adjust correction signals corresponding to changes in the speed of the recording light beam in real time. Here, a signal derived from the grating signal is used as the correction signal, and therefore, the circuit can be simplified by simply providing a multiplication circuit that performs the above-mentioned multiplication and matching.

以下、この発明の詳細な説明する。The present invention will be explained in detail below.

第4図は、画像走査記録装置全体を制御するために必要
な、同期信号を得るための公知の位相同期ループ回路(
以下、PLL回路と称する。)(3)の1例を示すもの
で、かかるPLL回路(3)は、通常、位相比較器0υ
、低域フィルタ働、電圧制御発振器(至)、分局器−か
ら構成されている。かかるPLL回路(3)に、前記し
た如くして得られるグレーティング信号fin (第6
図(a))が入力されると、通常第5図(c)に示す如
き分周された同期信号fontが得られる。ところでこ
のPLL回路(3)に用いられている低域フィルタ鵜の
出力電圧V LPFは第6図ら)の如く走査光ビームB
pの走査速度に対応し、VLPF ock4°v −(
7) (たtごし、k4は定数) で表わされる。
FIG. 4 shows a known phase-locked loop circuit (
Hereinafter, it will be referred to as a PLL circuit. ) (3), and such a PLL circuit (3) usually has a phase comparator 0υ
It consists of a low-pass filter, a voltage controlled oscillator, and a branching unit. In this PLL circuit (3), the grating signal fin (sixth
When the signal shown in FIG. 5(a) is input, a frequency-divided synchronization signal font as shown in FIG. 5(c) is usually obtained. By the way, the output voltage V LPF of the low-pass filter used in this PLL circuit (3) is the scanning light beam B as shown in Figure 6, etc.
Corresponding to the scanning speed of p, VLPF ock4°v −(
7) It is expressed as (t, k4 is a constant).

従ってこの低域フィルタ(イ)の出力信号V LPFの
ゲイン・オフセットをm整して反転させた信号※ VLPFと前記(6)式に示す走査面上での光量Eを乗
算すると、 VLPFXE安P−6−に4(定数) ・・・(8)と
なり、速度変化に関係のない一定値を得ることができる
Therefore, the output signal of this low-pass filter (A) V is a signal obtained by adjusting the gain and offset of LPF and inverting it.* When VLPF is multiplied by the amount of light E on the scanning plane shown in equation (6) above, VLPFXE AnP is obtained. -6- is 4 (constant)...(8), and a constant value unrelated to speed changes can be obtained.

第6図は上記原理を画像走査記録装置の走査側に適用し
た回路の1例を示すものであり、又第7図は第6図に示
した各信号波形を示したものである。まず第7図(a)
に示す如くの基準面例えば白色を光電走査して得た入力
画像信号VPはアンプf、Dを介してVPU(第7図(
d))として乗算器(22a)の一方の端子に入力され
る。一方、PLL回路(3)の低域フィルタに)から出
力される第7図ら)の如き信号V LPFは波形調整回
路(2aa)でゲインもしくはオフセット調整されて、
第7図(C)に示す如き信号VLPFに変換された後、
乗算回路(22eL)の他方の端子に入力される。乗算
器(22a)では前記2つの信号が掛は合わされ第7図
(e)の如くシェーディング補正された画像信号Vci
ataが得られる。該画像信号Vdataは次に、A/
1)変換回路(財)に入力され、階調修正等の信号処理
回路に)に入力される。
FIG. 6 shows an example of a circuit in which the above principle is applied to the scanning side of an image scanning recording apparatus, and FIG. 7 shows each signal waveform shown in FIG. 6. First, Figure 7(a)
The input image signal VP obtained by photoelectrically scanning a reference surface, for example, white, as shown in FIG.
d)) is inputted to one terminal of the multiplier (22a). On the other hand, the signal V LPF as shown in FIG.
After being converted into a signal VLPF as shown in FIG. 7(C),
It is input to the other terminal of the multiplication circuit (22eL). In the multiplier (22a), the two signals are multiplied together to produce a shading-corrected image signal Vci as shown in FIG. 7(e).
ata is obtained. The image signal Vdata is then A/
1) Input to a conversion circuit (product), and input to a signal processing circuit (for gradation correction, etc.).

第8図は画像走査記録装置の記録側にこの発明を適用し
た場合の1実施例を示すものであり、第9図は第8図に
於ける各信号の波形を示すものである。ここで用いられ
る光学系は記録光ビームBnがドライブ回路(5)で制
御される音響光学光変調素子(AOM)(6)で変調さ
れている点を除いては第1図に示した光学系と略同じで
ある。すなわちレーザ発振器(11b)から出力された
光ビームは記録光ビームBnとグレーティングビームB
Gに分岐され、該記録光ビームBRはガルバノミラ−(
至)と対物レンズα4更に、折返しミラー(15b)を
介してドラムD上に装着された感光材料Fに照射される
FIG. 8 shows an embodiment in which the present invention is applied to the recording side of an image scanning recording apparatus, and FIG. 9 shows the waveforms of each signal in FIG. 8. The optical system used here is the same as shown in Figure 1, except that the recording light beam Bn is modulated by an acousto-optic modulator (AOM) (6) controlled by a drive circuit (5). It is almost the same as That is, the light beam output from the laser oscillator (11b) is a recording light beam Bn and a grating beam B.
G, and the recording light beam BR is split into a galvanometer mirror (
) and the objective lens α4. Furthermore, the photosensitive material F mounted on the drum D is irradiated via the folding mirror (15b).

グレーティング信号を得るための光学系及びPLL回路
(3)は第6図に示したものと全く同じであり、両者は
走査側と記録側で共用することもできる。更に、グレー
ティングαのを通過した光ビームは受光センサアレイ(
ト)で光電変換されて、最終的には波形調整回路(28
b)から、第9図(c)の如き信号※ V LPFがアナログ乗算器(22b)に入力されるこ
とは第6図の説明内容と同じであるので詳述しない。
The optical system and PLL circuit (3) for obtaining the grating signal are exactly the same as those shown in FIG. 6, and both can be shared on the scanning side and the recording side. Furthermore, the light beam that has passed through grating α is sent to the light receiving sensor array (
It is photoelectrically converted by the waveform adjustment circuit (28
The fact that the signal *V LPF as shown in FIG. 9(c) is input from b) to the analog multiplier (22b) is the same as the content of the explanation in FIG. 6, and will not be described in detail.

画像信号処理回路(4)で階調鉦正され、更に網目版画
偉を記録するための信号に変換されtコ第9図(a)の
如き信号VBはアナログ乗算器(22b)に入力される
The gradation is corrected in the image signal processing circuit (4), and the signal VB, which is further converted into a signal for recording the mesh print size as shown in FIG. 9(a), is input to the analog multiplier (22b). .

上記の如くにアナログ乗算器(22b)に入力された信
号V LPFと信号V8は相互に掛は合わされて、第9
図(e)に示す如き信号Vout とな9、AOMドラ
イブ回路(5)に入力され、更にそのドライブ回路(5
)の出力信号VAOM (第9図(f))がAOM(6
)に入力されることによって第9図(g)の如くに変調
された記録光ビームBnを得る。この記録光ビームBR
が冒頭に記述した如くに信号Vo(=sinωt)で駆
動されるガルバノミラ−に入射偏向されることによって
第9図(ロ)に示す如くの露光紙が一定である記録画像
を得ることができるのである。
As mentioned above, the signal VLPF input to the analog multiplier (22b) and the signal V8 are multiplied together, and the ninth
The signal Vout as shown in FIG. 9(e) is input to the AOM drive circuit (5), and then
) output signal VAOM (Fig. 9(f)) is AOM(6
), a recording light beam Bn modulated as shown in FIG. 9(g) is obtained. This recording light beam BR
As described at the beginning, by being incident and deflected by the galvanometer mirror driven by the signal Vo (=sinωt), it is possible to obtain a recorded image in which the exposure paper is constant as shown in FIG. 9 (b). be.

なお、上記した説明では、この発明を走査側もしくは記
録側に適用した場合について記載したが、走査側および
記録側の両方同時に適用し得ることは自明である。また
、走査側だけから成る画像入力装置、または記録側だけ
から成る画像入力装置にも、それぞれ、適用できること
はいうまでもない。
In the above description, the present invention is applied to the scanning side or the recording side, but it is obvious that it can be applied to both the scanning side and the recording side at the same time. It goes without saying that the present invention can also be applied to an image input device consisting only of a scanning side or an image input device consisting only of a recording side.

以上説明した様にこの発明は走査側の画像信号又は記録
信号に、走査光ビーム又は記録光ビームの走査速度変化
に対応する補正信号をリアルタイムで掛は合わせるだけ
の簡単な方法を用いているので、補正係数を収納するた
めのメモリ装置や補正計算を行うための回路を必要とせ
ず、装置全体のコストを下げることができる等、実用上
多大の効果を有している。
As explained above, this invention uses a simple method of multiplying the image signal or recording signal on the scanning side in real time by a correction signal corresponding to the change in the scanning speed of the scanning light beam or recording light beam. This method has many practical effects, such as eliminating the need for a memory device for storing correction coefficients or a circuit for performing correction calculations, and reducing the cost of the entire device.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は画像走査記録装置の走査側の光学系図であり、
第2図は第1図主要部の拡大図であり、第8図は第1図
の光学系を用いた場合の走査面上の露光紙であり、第4
図はPLL回路図、第5図はPLL1路図の各部の電圧
波形図、第6図はこの発明を画像走査記録装置の走査側
に適用した場合の1実施例図、第7図は第6図の各部の
電圧波形図、第8図はこの発明を画像走査記録装置の記
録側に適用した場合の1実施例図、第9図は第8図の各
部の電圧波形図である。 第6図 32 第7図
FIG. 1 is a diagram of the optical system on the scanning side of the image scanning recording device.
Figure 2 is an enlarged view of the main part of Figure 1, Figure 8 is an exposed paper on the scanning surface when the optical system of Figure 1 is used, and
The figure is a PLL circuit diagram, FIG. 5 is a voltage waveform diagram of various parts of the PLL1 circuit diagram, FIG. FIG. 8 is a diagram showing an embodiment of the present invention when the present invention is applied to the recording side of an image scanning recording apparatus, and FIG. 9 is a voltage waveform diagram of various parts in FIG. 8. Figure 6 32 Figure 7

Claims (1)

【特許請求の範囲】 (1ン ガルバノミラ−等の光ビーム偏向手段によって
偏向される走査光ビームにより原画を走査線順次に光電
走査して得た画像信号に、走査光ビームにおける走査速
度の変化に対応して出力される、位相同期ループ回路の
低域フィルタからの出力信号に基づいて作成された補正
信号を、かけ合わせるようにしたことを特徴とする、シ
ェーディング補正方法。 (2)光ビーム偏向手段によって偏向される記録光ビー
ムにより感光材料を走査し、画像信号に所定のデータ処
理が施こされた記録信号に町って記録光ビームを変調制
御して複製画像を記録するに際し、記録信号に、記録光
ビームにおける走査速度の変化に対応して出力される、
位相同期ループ回路の低域フィルタからの出力信号に基
づいて作成された補正信号をかけ合わせるようにしたこ
とを特徴とする、シェーディング補正方法。
[Scope of Claims] A shading correction method characterized by multiplying correction signals created based on corresponding output signals from a low-pass filter of a phase-locked loop circuit. (2) Light beam deflection When recording a duplicate image by scanning a photosensitive material with a recording light beam deflected by a means and controlling the modulation of the recording light beam based on the recording signal obtained by performing predetermined data processing on the image signal, the recording signal is is output in response to changes in the scanning speed of the recording light beam.
A shading correction method characterized in that a correction signal created based on an output signal from a low-pass filter of a phase-locked loop circuit is multiplied.
JP58231084A 1983-12-06 1983-12-06 Correcting method of shading Granted JPS60123168A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
JP58231084A JPS60123168A (en) 1983-12-06 1983-12-06 Correcting method of shading
US06/671,984 US4691241A (en) 1983-12-06 1984-11-15 Method and system for compensating for a shading phenomenon
GB08430654A GB2151876B (en) 1983-12-06 1984-12-05 Shading correction in image reproducing system
DE19843444581 DE3444581A1 (en) 1983-12-06 1984-12-06 METHOD AND DEVICE FOR COMPENSATING A SHADOW PHENOMENON
GB08703957A GB2185654B (en) 1983-12-06 1987-02-20 Shading correction of image signal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP58231084A JPS60123168A (en) 1983-12-06 1983-12-06 Correcting method of shading

Publications (2)

Publication Number Publication Date
JPS60123168A true JPS60123168A (en) 1985-07-01
JPH0215153B2 JPH0215153B2 (en) 1990-04-11

Family

ID=16918031

Family Applications (1)

Application Number Title Priority Date Filing Date
JP58231084A Granted JPS60123168A (en) 1983-12-06 1983-12-06 Correcting method of shading

Country Status (1)

Country Link
JP (1) JPS60123168A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6169259A (en) * 1984-09-12 1986-04-09 Fuji Photo Film Co Ltd Read scanner provided with scanning speed variance compensating means
JPS6189765A (en) * 1984-10-08 1986-05-07 Fuji Photo Film Co Ltd Recording scanner

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6169259A (en) * 1984-09-12 1986-04-09 Fuji Photo Film Co Ltd Read scanner provided with scanning speed variance compensating means
JPH0520027B2 (en) * 1984-09-12 1993-03-18 Fuji Photo Film Co Ltd
JPS6189765A (en) * 1984-10-08 1986-05-07 Fuji Photo Film Co Ltd Recording scanner
JPH0521382B2 (en) * 1984-10-08 1993-03-24 Fuji Photo Film Co Ltd

Also Published As

Publication number Publication date
JPH0215153B2 (en) 1990-04-11

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