JPS60127441A - Apparatus for measuring radius mutual difference of rotary polyhedron mirror - Google Patents

Apparatus for measuring radius mutual difference of rotary polyhedron mirror

Info

Publication number
JPS60127441A
JPS60127441A JP23559583A JP23559583A JPS60127441A JP S60127441 A JPS60127441 A JP S60127441A JP 23559583 A JP23559583 A JP 23559583A JP 23559583 A JP23559583 A JP 23559583A JP S60127441 A JPS60127441 A JP S60127441A
Authority
JP
Japan
Prior art keywords
radius
light
polygon mirror
reflective surface
rotating polygon
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
Application number
JP23559583A
Other languages
Japanese (ja)
Inventor
Akira Oota
明 太田
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.)
Fujifilm Business Innovation Corp
Original Assignee
Fuji Xerox 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 Fuji Xerox Co Ltd filed Critical Fuji Xerox Co Ltd
Priority to JP23559583A priority Critical patent/JPS60127441A/en
Publication of JPS60127441A publication Critical patent/JPS60127441A/en
Pending legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M11/00Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
    • G01M11/005Testing of reflective surfaces, e.g. mirrors
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/08Measuring arrangements characterised by the use of optical techniques for measuring diameters

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Length Measuring Devices By Optical Means (AREA)
  • Testing Of Optical Devices Or Fibers (AREA)

Abstract

PURPOSE:To measure radius mutual difference rapidly and accurately, by allowing a rotary polyhedron mirror to position in a light beam path to detect the radius of a reflective surface on the basis of quantity of light blocked by the reflective surface. CONSTITUTION:A rotary polyhedron mirror 4 is arranged in the light path between a light source 11 and a light output measuring apparatus 12 so as to be partially blocked by the reflective surfaces 4a, 4b thereof. When light beam is emitted from the light source 11, it is partially blocked by the interposition of the reflective surface 4a and received by a measuring apparatus 12. An operation part 13 receiving the supply of this received light output signal operates the radius of the reflective surface 4a and similarly operates that of the reflective surface 4b. Subsequently, the operation part 13 operates the radius mutual difference from the radii of the reflective surfaces 4a, 4b. By this method, the radius mutual difference can be measured rapidly and accurately.

Description

【発明の詳細な説明】 (技術分野) 本発明は光ビームの光通路に回転多面鏡を位置させるこ
とによって反射面の半径相互差を適確に測定する回転多
面鏡の半径相互差測定装置に関する。
Detailed Description of the Invention (Technical Field) The present invention relates to a rotating polygon mirror radius difference measuring device that accurately measures the radius difference of reflective surfaces by positioning the rotating polygon mirror in the optical path of a light beam. .

(背景技術) 光線を高周波数で偏向するための回転多面鏡は、プリン
ター等の種々のものに用いられている。第1図は回転多
面鏡を用いたレーザ記録装置の一例を示すものである。
(Background Art) Rotating polygon mirrors for deflecting light beams at high frequencies are used in various devices such as printers. FIG. 1 shows an example of a laser recording device using a rotating polygon mirror.

このレーザ記録装置は平行光線16を発振するレーザ発
振器17と、平行光線16の方向全変位させるミ2−1
8a、18b、18c、18dと、モータ等により回転
し、平行光#jll 6’(i=走査方向に偏向させる
回転多面鏡4と、平行光線16の光束を制御する複数の
←≠、1−e−レンズ20g、20b。
This laser recording device includes a laser oscillator 17 that oscillates a parallel beam 16, and a laser oscillator 2-1 that oscillates the parallel beam 16 in all directions.
8a, 18b, 18c, 18d, a rotating polygon mirror 4 that is rotated by a motor or the like and deflects the parallel light #jll 6' (i=scanning direction), and a plurality of ←≠, 1- that controls the luminous flux of the parallel light 16. e-lens 20g, 20b.

20c、20d、20eと、平行光線161に画像信号
に応じて変調する変調器21と、光線によって静電潜像
が形成される感光ドラム22とよシ構成されている。以
上の構成において、レーザ発振器17から平行光線16
が発振されると、この平行光線16は第1ミラー18a
及び第2ミラー18bによシその方向を変位させられ、
レンズ20 a’ii:介して変調器21に入って画像
信号に応じて変調させられる。この変調光線はレンズ2
0b全通過した後、ミラー18Cによシ方向を変位させ
られ、レンズ20 c k介して回転多面鏡4に反射さ
れる。回転多面鏡4の反射によって変調光線は走査方向
に偏向され、レンズ20 d % 20 e 全弁して
進み、最終ミラー18dにより感光ドラム22に到達し
て所望の静電潜像を形成する。
20c, 20d, and 20e, a modulator 21 that modulates a parallel light beam 161 according to an image signal, and a photosensitive drum 22 on which an electrostatic latent image is formed by the light beam. In the above configuration, the parallel light beam 16 is emitted from the laser oscillator 17.
is oscillated, this parallel light ray 16 is reflected by the first mirror 18a.
and is displaced in that direction by the second mirror 18b,
The lens 20a'ii enters the modulator 21 via the lens 20a'ii and is modulated according to the image signal. This modulated light beam is transmitted through lens 2
After completely passing through 0b, it is displaced in the horizontal direction by the mirror 18C and reflected by the rotating polygon mirror 4 via the lens 20ck. The modulated light beam is deflected in the scanning direction by reflection from the rotating polygon mirror 4, travels through the lens 20d%20e, reaches the photosensitive drum 22 by the final mirror 18d, and forms a desired electrostatic latent image.

しかしながら、回転多面鏡の反射面の半径に差があると
感光ドラム上の走査位置にずれが生じ、それによって印
字品質が低下することがある@従って各反射面の半径相
互差金測定しなければならない。
However, if there is a difference in the radius of the reflective surface of the rotating polygon mirror, a shift may occur in the scanning position on the photosensitive drum, which may reduce print quality. Therefore, the difference in radius of each reflective surface must be measured. .

従来の回転多面鏡の半径相互差を測定する方法として、
例えば、以下の2方法がある。
As a method to measure the difference in radius of conventional rotating polygon mirrors,
For example, there are the following two methods.

(1) 第2図に示すような接触式変位計を用いる場合
(1) When using a contact displacement meter as shown in Figure 2.

この接触式変位計1は軸5會中心にして回転する多面鏡
4の反射面4aに接触して可動するシャフト2と、シN
フト2のひっこみによって反射面4aの半径を表示する
表示部3とから構成されている。即ち、反射面4aの半
径の測定にあたっては回転多面鏡4と、接触式変位計1
を所定箇所に固定する。接触式変位計1のシャフト2の
先端2ak回転多面鏡4の1つの反射面に接触させると
、表示部3がその際のシャフト2のひっこみ量に基いて
反射面4aの半径に応じた値を示す。次に、回転多面鏡
4t−回転させ、異なった反射面4b全前記シヤフト2
の先端2aに接する状態にすると、表示部3がシャフト
2のひっこみ量によシ反射面4bの半径に応じた値を表
示する。この操作を回転多面鏡4の反射面の数(第2図
においては8回)だけ行い、各反射面の半径相互差を測
定する。
This contact type displacement meter 1 consists of a shaft 2 that is movable in contact with a reflective surface 4a of a polygon mirror 4 that rotates around an axis 5,
The display section 3 displays the radius of the reflective surface 4a when the lift 2 is retracted. That is, in measuring the radius of the reflecting surface 4a, a rotating polygon mirror 4 and a contact displacement meter 1 are used.
Fix it in place. When the tip 2ak of the shaft 2 of the contact type displacement meter 1 is brought into contact with one reflective surface of the rotating polygon mirror 4, the display section 3 displays a value corresponding to the radius of the reflective surface 4a based on the amount of retraction of the shaft 2 at that time. show. Next, the rotating polygon mirror 4t is rotated, and the different reflecting surfaces 4b are all aligned with the shaft 2.
When the shaft 2 is in contact with the tip 2a, the display section 3 displays a value corresponding to the amount of retraction of the shaft 2 and the radius of the reflective surface 4b. This operation is repeated for the number of reflecting surfaces of the rotating polygon mirror 4 (eight times in FIG. 2), and the mutual difference in radius of each reflecting surface is measured.

しかしながら、この方法にあってはシャフト2の先端2
af、24度の高い鏡面状態を必要とされる回転多面鏡
の反射面に接触させるため、反射面を傷つける恐れがあ
る。
However, in this method, the tip 2 of the shaft 2
Since the mirror is brought into contact with the reflective surface of the rotating polygon mirror, which requires a high mirror surface condition of 24 degrees af, there is a risk of damaging the reflective surface.

(2)第3図に示すような非接触式変位計を用いる場合
(2) When using a non-contact displacement meter as shown in Figure 3.

この非接触式変位計6はうず電流全利用したもので一次
コイル7と二次コイル8よシ成シ、−次コイル7には交
番磁界金主じさせる電源9が接続されておシ、二次コイ
ル8には二次コイルに発生する誘導電流全測定してその
値全表示する表示部10が設けられている。
This non-contact type displacement meter 6 makes full use of eddy current and consists of a primary coil 7 and a secondary coil 8. The secondary coil 8 is provided with a display section 10 that measures all induced currents generated in the secondary coil and displays all of the values.

以上の構成において、その操作を説明すると、−次コイ
ル7に交流合流して回転多面鏡4の1つの反射面4aに
対面させると、反射面4aの部分に一次コイル7の交番
磁界(−次磁界)に基いてうず電流が生ずる。このうず
電流にょ9発生する交番磁界は二次コイル8の一次コイ
ル7に基く誘導作用金波する方向に作用するたべその減
少度は回転多面鏡4と変位計6の距離に応じて変化する
。従って、二次コイル8の誘導電流の測定により各反射
面4 a、 4 bs 4 C%4d、4e、4f、4
g、4hの半径相互差を測定することができる。
In the above configuration, the operation will be explained. When the -order coil 7 is joined with alternating current and made to face one reflective surface 4a of the rotating polygon mirror 4, the alternating magnetic field of the primary coil 7 (-order (magnetic field), eddy currents are generated. The alternating magnetic field generated by this eddy current 9 acts in the direction of the induction effect based on the primary coil 7 of the secondary coil 8, and the degree of reduction thereof changes depending on the distance between the rotating polygon mirror 4 and the displacement meter 6. Therefore, by measuring the induced current of the secondary coil 8, each reflecting surface 4a, 4bs4C%4d, 4e, 4f, 4
The mutual difference in radius between g and 4h can be measured.

しかしながら、この非接触式変位計6によれば、回転多
面鏡に接触させないで測定するたべ測定点の位置決めに
時間がかがシ、また反射面金てに変位計のセツティング
を行なわなければならないため、迅速な測定ができない
恐れがある。更に反射面に用いられる材質によってはう
ず電流の発生が微少で測定が不可能であるという不具合
が生ずる。
However, with this non-contact displacement meter 6, it takes time to position the measurement point without contacting the rotating polygon mirror, and the displacement meter must be set on the reflective surface. Therefore, quick measurements may not be possible. Furthermore, depending on the material used for the reflective surface, the generation of eddy current is so small that it is impossible to measure it.

(発明の目的及び構成) 本発明は上記に鑑みてなされたものであシ、回転多面鏡
の反射面を傷つけず、迅速且つ正確に回転多面鏡の半径
相互差を測定するため、光ビームの通路に回転多面鏡を
位置させてその反射面により遮蔽される光量に基いて反
射面の半径を検出する回転多面鏡の半径相互差測定装置
を提供するものである。
(Objective and Structure of the Invention) The present invention has been made in view of the above, and is intended to quickly and accurately measure the mutual radius difference of a rotating polygon mirror without damaging the reflecting surface of the rotating polygon mirror. The present invention provides an apparatus for measuring the difference in radius of a rotating polygon mirror, which detects the radius of a reflecting surface based on the amount of light blocked by the reflecting surface by positioning the rotating polygon mirror in a passage.

以下、添附図面に示す実施例にもとづき、この発明の詳
細な説明する。
Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

(実施例) 第4図は本発明の一実施例全示し、光ビーム14a(i
)放射する光源11(例えば、ビーム径がOr ” l
+1lllのT−1e−Neレーザ金用いる)と、その
光源11の光を受光し、且つ受光した光の出力を測定す
る光出力測定装置12(例えば、外径が2M程度のシリ
コンフォトディテクタを用い局が所定間隔にて設けられ
ている。光出力測定装置には測定された光出力信号を入
力して演算する演算部13と接続され、演算部13は演
算結果全表示する表示部14に接続されている。光源1
1と光出力測定装置]2の間の光通路には、反射面4a
、4b、4c、4d、4e、4f。
(Embodiment) FIG. 4 shows an entire embodiment of the present invention, in which the light beam 14a (i
) emitting light source 11 (for example, a beam diameter of Or ” l
+1llll T-1e-Ne laser gold) and a light output measuring device 12 (for example, a silicon photodetector with an outer diameter of about 2M) that receives the light from the light source 11 and measures the output of the received light. are provided at predetermined intervals.The optical output measuring device is connected to a calculation section 13 that inputs and calculates the measured optical output signal, and the calculation section 13 is connected to a display section 14 that displays all the calculation results. Light source 1
1 and the optical output measuring device] In the optical path between 2, there is a reflective surface 4a.
, 4b, 4c, 4d, 4e, 4f.

4 g % 4 hがその一部を遮断するように回転多
面鏡4が軸5を中心にして回転的に固定されている。
A rotating polygon mirror 4 is rotationally fixed about a shaft 5 so that 4 g % 4 h blocks a portion of the polygon mirror 4 .

以上の構成において、その操作全説明するに、光源11
より光ビームIla’ji放射すると、回転多面鏡4の
反射面4aの介在によシ光ビームは一部遮断されて光出
力測定装置12に受光され、その受光された光出力信号
が演算部13に入力する。入力した光出力信号は演算部
13にて所定のプログラムに基づき演算され、回転多面
鏡4の中心点(軸5)から反射面4aまでの半径が表示
部14に表示される。その際の光ビームllaの断面の
強度分布は第5図(イ)に示す通りであシ(光ビームl
laの中心部が最も光が強い)、また第5図(ロ)は遮
光がある場合と遮光がない場合の光出力測定装置f12
における光出力の変化を示すものである。次に、反射面
4aの半径測定終了後、回転多面鏡4を時計方向に回転
すると、反射面4bが光ビームllaの光路内に介在す
る。同様にして表示部14に回転多面鏡4の中心点から
反射面4bまでの半径が表示される。演算部13の演算
操作全簡易化するため、第5図(ロ)の直線部(A−B
の範囲)を利用すると、光出力の変化1%に対して5μ
mの反射面4a、4b、4c、4d、4fs 4g。
In the above configuration, to fully explain its operation, the light source 11
When a light beam Ila'ji is emitted from the rotating polygon mirror 4, the light beam is partially blocked by the interposition of the reflecting surface 4a of the rotating polygon mirror 4 and is received by the light output measuring device 12, and the received light output signal is transmitted to the calculation unit 13. Enter. The input optical output signal is calculated in the calculation unit 13 based on a predetermined program, and the radius from the center point (axis 5) of the rotating polygon mirror 4 to the reflective surface 4a is displayed on the display unit 14. At that time, the intensity distribution of the cross section of the light beam lla is as shown in Fig. 5(a).
The light is strongest in the center of la), and Figure 5 (b) shows the light output measuring device f12 with and without light shielding.
This shows the change in light output at . Next, after the radius measurement of the reflective surface 4a is completed, when the rotating polygon mirror 4 is rotated clockwise, the reflective surface 4b is interposed in the optical path of the light beam lla. Similarly, the radius from the center point of the rotating polygon mirror 4 to the reflective surface 4b is displayed on the display section 14. In order to simplify the calculation operation of the calculation unit 13, the straight line part (A-B
range), 5μ for 1% change in optical output.
m reflective surfaces 4a, 4b, 4c, 4d, 4fs 4g.

4hの出入り、即ち、半径相互差を測定することがで炒
る。第6図は8面の反射面1.2.3.4.5.6.7
.8を有する回転多面鏡の半径を測定した結果を示し、
包絡線15によって半径相互差を知ることができる。各
反射面1、本3.4.5.6.7.8の間を結ぶ曲線は
光ビームl1mが各反射面1.2.3.4.5、ξ7.
8間の境界部によって遮断されることによって光出力が
変動することを示している。
This is done by measuring the inflow and outflow of 4h, that is, the mutual difference in radius. Figure 6 shows 8 reflective surfaces 1.2.3.4.5.6.7
.. Showing the results of measuring the radius of a rotating polygon mirror having 8,
The difference in radius can be determined by the envelope 15. The curve connecting each reflective surface 1 and book 3.4.5.6.7.8 is such that the light beam l1m is connected to each reflective surface 1.2.3.4.5, ξ7.
8 shows that the optical output varies due to the interruption by the boundary between the two.

(発明の効果) 以上説明した通り、本発明による回転多面鏡の半径相互
差測定装置によれば、光ビームの通路に回転多面鏡全位
置させてその反射面によシ遮蔽される光量に基いて反射
面の半径を検出するため、回転多面鏡の反射面を傷つけ
ず、迅速且つ正確に回転多面鏡の半径相互差を測定する
ことができる。
(Effects of the Invention) As explained above, according to the rotating polygon mirror radius mutual difference measuring device according to the present invention, the rotating polygon mirror is entirely positioned in the path of the light beam, and the amount of light that is blocked by the reflecting surface is measured. Since the radius of the reflecting surface is detected by using the rotating polygon mirror, it is possible to quickly and accurately measure the difference in radius of the rotating polygon mirror without damaging the reflecting surface of the rotating polygon mirror.

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

第1図は回転多面鏡音用いたレーザ記録装置の説明図、
第2図及び第3図は従来の回転多面鏡の半径相互差測定
装置の構造説明図、第4図は本発明による半径相互差測
定装置の構造説明図、第5図(イ)は光ビームの断面の
強度分布金示す説明図、第5図(ロ)は遮光の有無によ
る光出力測定装置の光出力の変化を示す説明図、第6図
は回転へ面鏡の半径全測定した結果の包絡線を示した説
明図である。 符号の説明 4・・・回転多面鏡、 11・・・光源、 lla・・
・光ビーム、12・・・光出力測定装置、13・・・演
算部、 14・・・表示部 特許出願人 富士ゼロックス株式会社 代理人 弁理士 松 原 伸 2 同 弁理士 村 木 清 同 門 弁理士 平 1) 忠 離 開 弁理士 上 島 淳 − 同 弁理士 鈴 木 均 第1図 第2図
Figure 1 is an explanatory diagram of a laser recording device using rotating polygon mirror sound.
2 and 3 are structural explanatory diagrams of a conventional radius mutual difference measuring device for a rotating polygon mirror, FIG. 4 is a structural diagram of a radius mutual difference measuring device according to the present invention, and FIG. 5 (a) is a light beam Figure 5 (b) is an explanatory diagram showing the change in the optical output of the optical output measuring device depending on the presence or absence of light shielding, and Figure 6 is an explanatory diagram showing the intensity distribution of the cross section of the rotating mirror. It is an explanatory diagram showing an envelope. Explanation of symbols 4...Rotating polygon mirror, 11...Light source, lla...
・Light beam, 12...Light output measuring device, 13...Calculating unit, 14...Display unit Patent applicant Fuji Xerox Co., Ltd. Agent Patent attorney Shin Matsubara 2 Patent attorney Kiyoshi Muraki Fellow Patent attorney Heisei 1) Patent attorney Atsushi Ueshima - Patent attorney Hitoshi Suzuki Figure 1 Figure 2

Claims (1)

【特許請求の範囲】[Claims] 回転多面鏡全中間に位置させ、その反射面の半径に応じ
て遮断される断面積が変化する光ビーム全送受する発光
部および受光部と、該受光部が受光する前記光ビームの
受光量に基いて前記回転多面鏡の半径相互差を演算する
演算部とを備えたこと全特徴とする回転多面鏡の半径相
互差測定装置。
A light-emitting part and a light-receiving part are located in the middle of the rotating polygon mirror and transmit and receive a light beam whose cross-sectional area changes depending on the radius of the reflecting surface, and the amount of light received by the light-receiving part is 1. A calculation unit that calculates a mutual radius difference of the rotating polygon mirror based on the above-mentioned calculation unit.
JP23559583A 1983-12-14 1983-12-14 Apparatus for measuring radius mutual difference of rotary polyhedron mirror Pending JPS60127441A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP23559583A JPS60127441A (en) 1983-12-14 1983-12-14 Apparatus for measuring radius mutual difference of rotary polyhedron mirror

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP23559583A JPS60127441A (en) 1983-12-14 1983-12-14 Apparatus for measuring radius mutual difference of rotary polyhedron mirror

Publications (1)

Publication Number Publication Date
JPS60127441A true JPS60127441A (en) 1985-07-08

Family

ID=16988325

Family Applications (1)

Application Number Title Priority Date Filing Date
JP23559583A Pending JPS60127441A (en) 1983-12-14 1983-12-14 Apparatus for measuring radius mutual difference of rotary polyhedron mirror

Country Status (1)

Country Link
JP (1) JPS60127441A (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100600319B1 (en) * 2003-06-25 2006-07-14 미쯔비시 지도샤 고교 가부시끼가이샤 Air-fuel ratio control apparatus for multiple cylinder

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