JPS6358315A - Laser scanning optical system - Google Patents
Laser scanning optical systemInfo
- Publication number
- JPS6358315A JPS6358315A JP20125886A JP20125886A JPS6358315A JP S6358315 A JPS6358315 A JP S6358315A JP 20125886 A JP20125886 A JP 20125886A JP 20125886 A JP20125886 A JP 20125886A JP S6358315 A JPS6358315 A JP S6358315A
- Authority
- JP
- Japan
- Prior art keywords
- optical system
- scanned
- light
- image formation
- image
- 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
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 90
- 238000003384 imaging method Methods 0.000 claims description 42
- 230000004907 flux Effects 0.000 abstract description 8
- 230000015572 biosynthetic process Effects 0.000 abstract description 7
- 230000000903 blocking effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 235000010724 Wisteria floribunda Nutrition 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/0018—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00 with means for preventing ghost images
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、レーザープリンター等に用いられる走査光学
系に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a scanning optical system used in laser printers and the like.
従来の技術
第３図は、レーザー光束の走査光学系として従来より広
く一般に用いられているシングルパス方式の代表的構成
を示すものでおり、レーザー光源１より、結像光学系１
１の光軸を含み、偏向器４の回転軸と直交する平面にｑ
４出された光束は、コリメーターレンズ２及びシリンド
リカルレンズ３により、回転多面鏡よりなる園光器４の
一反剣面上に線状に結保され、偏光器の回転に伴い反削
偏面された後、結像光学系５、シリンドリカルレンズ６
を）頃次通過し、被走査面７に結像スポラＩ〜を形成し
、被走査面を走査するようにしたものである。BACKGROUND ART FIG. 3 shows a typical configuration of a single-pass system that has been widely used as a laser beam scanning optical system.
q in a plane containing the optical axis of 1 and perpendicular to the rotation axis of the deflector 4.
4. The emitted light beam is condensed into a linear shape by the collimator lens 2 and the cylindrical lens 3 on the one-sided plane of the Sonoko device 4, which is a rotating polygon mirror, and as the polarizer rotates, After that, the imaging optical system 5, the cylindrical lens 6
), the image formation spora I~ is formed on the surface to be scanned 7, and the surface to be scanned is scanned.
該走査光学系では、？ｉ５４図に示すごとく被走査面７
上に入射した光束は、該被走査面上で拡散反射し、この
反射光の一部はシリンドリカルレンズ６、結像光学系１
１を通り、再び偏向器４に入射する。偏光器に入射した
光束のうち、反射面４ａに隣接する反射面４ｂに入射し
た光束は再度結像光学系１１、シリンド１ノカルレンズ
６を通り被走査面」−に結像し、結像点か、被走査面の
画像形成領域におる場合には有害なゴースミル像を形成
するものでおる。In the scanning optical system? i54 As shown in figure 7, scanned surface 7
The light flux incident above is diffusely reflected on the scanned surface, and a part of this reflected light is reflected by the cylindrical lens 6 and the imaging optical system 1.
1 and enters the deflector 4 again. Among the light beams incident on the polarizer, the light beams incident on the reflection surface 4b adjacent to the reflection surface 4a pass through the imaging optical system 11, the cylinder 1 nocal lens 6 again, form an image on the scanned surface, and form an image at the imaging point. , if it is located in the image forming area of the scanned surface, it will form a harmful Gauss Mill image.
上記ゴースト像を防止する方法として、特開昭５８−６
８０１４公報に於いて、偏光器に入射する光束の光軸に
対する角度を選定することに依り、ゴースト像を画像形
成領域外に形成させる方法、更には、上記ゴースト画像
を形成する光束を遮断するための遮光板を設けた走査光
学系が提案されている。As a method for preventing the above-mentioned ghost image, Japanese Patent Laid-Open No. 58-6
Publication No. 8014 discloses a method for forming a ghost image outside an image forming area by selecting the angle of the light beam incident on a polarizer with respect to the optical axis, and furthermore, a method for blocking the light beam forming the ghost image. A scanning optical system equipped with a light shielding plate has been proposed.
以上、述べたシングルパス方式に比較し、広い走査角度
が実現でき、小型化が容易等の特徴をイ１するダブルパ
ス方式の走査光学系が提案されている。第２図は、ダブ
ルパス方式走査光学系の構成を示すものである。As compared to the single-pass system described above, a double-pass system scanning optical system has been proposed, which has the following features: a wider scanning angle and easier miniaturization. FIG. 2 shows the configuration of a double-pass type scanning optical system.
レーザー光源１より偏光器４の回転軸と結像光学系１１
の光軸を含む平面内に光軸と或る角度をもって射出され
た光束は、絞り込みレンズ８によって、−旦被走査面７
上に結像した後、トロイダルレンズ９、結像レンズ５を
通り偏光器４の一反則面上に線状に結像され、偏向器の
回転に伴ない、反則偏向された後、再度、トロイダルレ
ンズ９、結像レンズ５を通過し、被走査面７上に点像を
形成し被走査面上を走査するように構成したものである
。From the laser light source 1 to the rotation axis of the polarizer 4 and the imaging optical system 11
The light beam emitted at a certain angle to the optical axis within a plane containing the optical axis of
After the image is formed upward, it passes through the toroidal lens 9 and the imaging lens 5, and is formed into a linear image on one non-uniform surface of the polarizer 4, and after being non-deflected as the deflector rotates, the toroidal image is formed again. It passes through a lens 9 and an imaging lens 5, forms a point image on a surface to be scanned 7, and scans the surface to be scanned.
発明が解決しようとする問題点
上記のようなダブルパス方式の走査光学系では、レーザ
ー光源装置１０からの光束か結像レンズ系１１を通過す
る際、各レンズの各面にあける１次陵剣光が、画面上で
光軸と直交する線上で走査線の近傍に入射し、いわゆる
１次ゴースト像を生ずるという欠点を有していた。Problems to be Solved by the Invention In the double-pass type scanning optical system as described above, when the light beam from the laser light source device 10 passes through the imaging lens system 11, a primary beam of light is formed on each surface of each lens. However, it has the disadvantage that it is incident on the screen near the scanning line on a line perpendicular to the optical axis, producing a so-called primary ghost image.
従って、本発明の目的は１次ゴース１〜像を除去したダ
ブルパス方式の走査光学系を提供することでおる。Therefore, an object of the present invention is to provide a double-pass type scanning optical system in which the primary goth 1 to image are removed.
問題点を解決するための手段
本発明者らは、検討の結果、走査面上で走査光線の近傍
に入射して、１次ゴースト像となるレンズ面での一次反
射光束が、光路中で互いに近接して光軸と交叉する事実
に着目し、一つの遮光手段を用いて複数の光束を結像レ
ンズへの入射光束、走査光束を妨害する事なく遮光し、
ゴースト像の発生を防止できることを見出だし、本発明
を完成するに至った。Means for Solving the Problems As a result of study, the inventors found that the primary reflected light beams that are incident on the scanning surface in the vicinity of the scanning beam and become primary ghost images on the lens surface mutually interact in the optical path. Focusing on the fact that they intersect the optical axis in close proximity, a single light blocking means is used to block multiple light beams without interfering with the light beam entering the imaging lens or the scanning light beam.
They have discovered that it is possible to prevent the generation of ghost images, and have completed the present invention.
即ら、本発明は、レーザー光源装置、結像光学系、及び
（偏向器よりなり、結像光学系の光軸と偏向器の回転１
仙を含む平面内にあって、結像光学系の光軸と一定角度
を持って結像光学系へ入射する光束か、［偏向器により
反射、偏向された後、再び前記結像光学系を通過し、被
走査媒体を走査するように構成した走査光学系に於いて
、被走査媒体側から結像光学系へ入射し、該結像光学系
のレンズ面で１次反射し、被走査媒体へ向う光束を遮断
するための遮光手段を光軸上に設けたことを特徴とする
。That is, the present invention comprises a laser light source device, an imaging optical system, and a deflector, and the optical axis of the imaging optical system and the rotation of the deflector
Either the light beam is in a plane including the center and enters the imaging optical system at a certain angle with the optical axis of the imaging optical system, or it is reflected and deflected by a deflector and then passes through the imaging optical system again. In the scanning optical system configured to scan the scanned medium, the light enters the imaging optical system from the side of the scanned medium, is primarily reflected on the lens surface of the imaging optical system, and is reflected on the scanned medium. It is characterized in that a light shielding means is provided on the optical axis for blocking the light beam directed toward the optical axis.
本発明の走査光学系は、遮光手段を設けた点以タトは、
例えば、第３図に示したものと同様な構成をイアする。The scanning optical system of the present invention has the following features since it is provided with a light shielding means.
For example, a configuration similar to that shown in FIG. 3 may be used.
すなわち、レーザー光源装置は、シー１アー光源１、コ
リメーターレンズ２および絞りＩノノズ８より構成され
、結像光学系は、結像レンズ５およびトロイダルレンズ
９よりなり、そして、結像光学系の光軸と偏向器４の回
転軸を含む平面内にあって、結像光学系の光軸と或る角
度をもって結像光学系に入則する光束が、偏向器４によ
り反則、鍋光された後、再び前記結像光学系を通り、被
走査面７を走査するように構成されている。そして、本
発明のレーザー走査光学系においては、結像光学系と被
走査媒体間の光軸上に遮光手段を設けた点に特徴を有す
る。That is, the laser light source device is composed of a seer light source 1, a collimator lens 2, and an aperture I nozzle 8, and an imaging optical system is composed of an imaging lens 5 and a toroidal lens 9. A light beam that is in a plane including the optical axis and the rotation axis of the deflector 4 and enters the imaging optical system at a certain angle with the optical axis of the imaging optical system is deflected by the deflector 4 and is turned into a pot light. Thereafter, it passes through the imaging optical system again and scans the surface to be scanned 7. The laser scanning optical system of the present invention is characterized in that a light shielding means is provided on the optical axis between the imaging optical system and the medium to be scanned.
作用
本発明の作用を第５図によって説明すると、レーザー光
源装置からの入射光束へは、結像光学系の光軸と或る角
度をもって偏向器に入則し、偏向器４の一反射面上に線
上に結像され、偏向器の回転に伴って反０”Ｊ偏光され
て、ｑＪ出光束Ｂとなって被走査面７上に結像される。Function To explain the function of the present invention with reference to FIG. 5, the incident light beam from the laser light source device enters the deflector at a certain angle with the optical axis of the imaging optical system, and is directed onto one reflecting surface of the deflector 4. The light beam is imaged on a line, and as the deflector rotates, it is polarized in an anti-0''J direction, and becomes a qJ output light beam B, which is imaged on the surface to be scanned 7.
この際、結像光学系の各レンズの表面で反０’Ｊが起っ
て一次反射光束が発生し被走査面上に結像された点像の
付近に入Ｑ”１し、交点Ｑ工、ＱＩＩ、ＱＩＩＩ等とな
ってゴースｉ・像を発生ずるが、本発明においては、結
像光学系と被走査媒体間の光軸上に遮光手段１２を設け
たから、−時反則光束Ｃは遮光され、被走査面上に到達
しない。したがって、ゴースト像の発生が防止される。At this time, anti-0'J occurs on the surface of each lens of the imaging optical system, a primary reflected light beam is generated, enters Q"1 near the point image formed on the scanned surface, and crosses Q"1. . Therefore, the generation of ghost images is prevented.
実施例 本発明の詳細を以下に実施例をもって説明する。Example The details of the present invention will be explained below with reference to Examples.
結像光学系１１は、３枚のレンズからなり、各レンズ面
の曲率、レンズ面間距離、屈折率が下表の通りであり、
結像光学系１１への入射光束Ａが結像光学系１１の光軸
に対し３°の角度で入射する場合について、本発明の実
施例を示す。尚、下表に於いてレンズ面番号は、偏光器
４側から順次■、■、■・・・の番号を付している。。The imaging optical system 11 consists of three lenses, and the curvature of each lens surface, distance between lens surfaces, and refractive index are as shown in the table below.
An embodiment of the present invention will be described with respect to a case where the incident light beam A to the imaging optical system 11 is incident at an angle of 3° with respect to the optical axis of the imaging optical system 11. In the table below, the lens surface numbers are sequentially numbered from the polarizer 4 side as ■, ■, ■, etc. .
また、レンズ曲率半径の符号は、偏向器側に凹の場合を
負としている。Further, the sign of the lens radius of curvature is negative when it is concave toward the deflector side.
この実施例の結像光学系の（育成において、各レンズ面
での１次反射光について光線追跡を行なった結果、例え
ば、第工面、第１Ｖ面、第Ｖ１面での反則光は、結像光
学系の光軸に関して入射光と同じ側に反射されるため、
ゴース１へ像を生ずることはなく、第■面ミ第■面、第
Ｖ面に於ける反ｑ１光（Ｊｌ、結像光学系光軸に関し、
入Ｑ＝Ｊ光と反対側に反ｑ１されゴースト像の原因とな
っている事が明らかとなった。As a result of ray tracing of the primary reflected light on each lens surface of the imaging optical system of this example (in the development), for example, the repulsive light on the 1st working surface, 1st V surface, and V1 surface is Because it is reflected on the same side of the optical axis of the optical system as the incident light,
It does not produce an image on the Goth 1, and the anti-q1 light (Jl, regarding the optical axis of the imaging optical system,
It became clear that q1 was reflected to the opposite side of the incoming Q=J light, causing the ghost image.
第１図は、これら第■面、第■面、第Ｖ面に於ける１次
反則光Ｃの光路図であり、第■面、第■面、第Ｖ面での
１次反射光Ｃが光軸と交叉する点をぞれぞれＰ■、ＰＩ
［Ｉ、ＰＶとし、被走査面に入射する点をそれぞれＱＩ
Ｉ、ＱＩ［Ｉ、ＱＶとして表している。これら各点の位
置関係を針線により求めた結果は下表に示す通りであり
、点Ｑ■、ＱＩ、ＱＶの光１ｒｑｂからの高さは、走査
光線の被走査面上での光線高さ１５．７Ｍを中心とし、
その近傍に分イ１していることか判る。また、点Ｐ■、
ＰＩＩＩ、ＰＶは被走査面からの距離が約３１１ｍの光
軸上の点（Ｐ点）を中心にして、その近傍に分布してい
る。Ｐ点における第■面、第■面、第Ｖ面からの１次反
射光の光線高さは、この点おける入射光線、及び走査光
線の光軸からの高さに比べ低いため、被走査面からの距
離が３１１＃の光軸上の点に遮光手段１２を設けその大
きさ適宜に選ぶことにより入射光束、走査光束を遮るこ
となく、１つの遮光手段１２によって第■面、第■面、
第Ｖ面からの１次反射光Ｃを全て除去することができる
。Figure 1 is an optical path diagram of the primary reflected light C on the 2nd surface, 2nd surface, and Vth surface. The points that intersect with the optical axis are P■ and PI, respectively.
[I, PV, and the point of incidence on the scanned surface is QI.
It is expressed as I,QI[I,QV. The results of determining the positional relationship of these points using needle lines are shown in the table below, and the heights of points Q■, QI, and QV from the light 1rqb are the ray height 15 of the scanning beam on the scanned surface. Focusing on .7M,
It can be seen that there are 1 parts in the vicinity. Also, point P■,
PIII and PV are distributed in the vicinity of a point on the optical axis (point P) that is approximately 311 m away from the scanned surface. The ray height of the primary reflected light from the ①, ①, and V surfaces at point P is lower than the height from the optical axis of the incident ray and the scanning ray at this point, so By providing a light shielding means 12 at a point on the optical axis at a distance of 311# from the light beam and appropriately selecting its size, one light shielding means 12 can be used to detect the surface (①), the second surface (③),
All of the primary reflected light C from the V-th surface can be removed.
例えば遮光手段として、遮光板、反！ＪＪ ｉ、６を使
用することかできるが、遮光板または反ＯＪ’＆Ａで反
則された光か迷光となって被走査面上の画像領域に達し
画像を劣化させない事か必要で必る。そのための要件は
遮光板においては、黒色もしくは使用するレーザー波長
での反射率の低い表面を持った材料を使用することであ
り、反射ミラーについては、反射ミラーでの反射光が結
像光学系へ入射しない角度に設定することである。For example, as a light shielding means, a light shielding plate, anti! JJ i,6 can be used, but it is necessary to prevent the light reflected by the light shielding plate or the anti-OJ'&A from becoming stray light and reaching the image area on the scanned surface and deteriorating the image. The requirements for this are that the light-shielding plate must be black or a material with a surface that has low reflectance at the laser wavelength used, and the reflective mirror must ensure that the light reflected from the reflective mirror is directed to the imaging optical system. It is necessary to set the angle at which no light is incident.
発明の効果
以上説明した通り本発明は、結像光学系の光軸上の適宜
の位置に適宜の大きざの遮光手段を設けることにより、
画像を損なうことなく、かつ、簡便に有害光を除去する
事ができる。Effects of the Invention As explained above, the present invention provides light shielding means of an appropriate size at an appropriate position on the optical axis of the imaging optical system.
Harmful light can be easily removed without damaging the image.
第１図は、本光の一実施例を示す走査光学装置の５１明
図、第２図は、ダブルパス方式の走査光学装置の平面図
及び側面図、第３図は、従来のシングルパス方式の走査
光学装置の平面図、第４図は、第３図のゴース１〜像発
生メカニズムの説明図である。
１・・・レーザー光源、２・・・コリメーターレンズ、
３・・・シリンドリカルレンズ、４・・・偏光器、４ａ
及び４ｂ・・・反則面、５・・・結像レンズ、６・・・
シリンドリカルレンズ、７・・・被走査面、８・・・絞
り込レンズ、９・・・トロイダルレンズ、１０・・・レ
ーザー光源装置、１１・・・結像光学系、１２・・・遮
光手段、Ａ・・・入射光束、Ｂ・・・射出光束、Ｃ・・
・１次反射光束、Ｐ■、Ｐ■、ＰＶ・・・結像光学系の
第■面、第■面、第Ｖ面に於ける１次反ｑ」光の光軸と
の交点、Ｑｎ、Ｑｌ、ＱＶ・・・結像光学系の第■面、
第■面、第Ｖ面における１次反射光の被走査面との交点
、王、■、■、ＩＬＬＶＩ・・・結像光学系の面番号。
特許出願人 富士ピロツクス株式会社代理人
弁理士 洞部 剛
（ｂ）
篤２図Fig. 1 is a 51-color diagram of a scanning optical device showing one embodiment of the present light, Fig. 2 is a plan view and side view of a double-pass type scanning optical device, and Fig. 3 is a conventional single-pass type scanning optical device. FIG. 4, a plan view of the scanning optical device, is an explanatory diagram of the image generation mechanism from the gaze 1 of FIG. 3. 1...Laser light source, 2...Collimator lens,
3... Cylindrical lens, 4... Polarizer, 4a
and 4b... fouling surface, 5... imaging lens, 6...
Cylindrical lens, 7... Surface to be scanned, 8... Stop lens, 9... Toroidal lens, 10... Laser light source device, 11... Imaging optical system, 12... Light blocking means, A...Incoming light flux, B...Outgoing light flux, C...
・Primary reflected light flux, P■, P■, PV...The intersection point with the optical axis of the primary anti-q' light on the 2nd surface, 2nd surface, and Vth surface of the imaging optical system, Qn, Ql, QV...the first surface of the imaging optical system,
Intersection of the primary reflected light with the scanned surface on the 2nd surface and the Vth surface, King, 2, 2, ILLVI...Surface number of the imaging optical system. Patent applicant Fuji Pilots Co., Ltd. Agent
Patent attorney Tsuyoshi Horabe (b) Atsushi 2
Claims (1)
結像光学系の光軸と偏向器の回転軸を含む平面内にあつ
て、結像光学系の光軸と或る角度をもつて結像光学系に
入射する光束が、偏向器により反射、偏向された後、再
び前記結像光学系を通り、被走査媒体を走査するよう構
成した走査光学系に於いて、結像光学系と被走査媒体間
の光軸上に遮光手段を設けたことを特徴とする走査光学
系。Consists of a laser light source device, an imaging optical system, and a deflector,
A light beam that enters the imaging optical system at a certain angle to the optical axis of the imaging optical system within a plane that includes the optical axis of the imaging optical system and the rotation axis of the deflector is reflected by the deflector. In the scanning optical system configured to pass through the imaging optical system again after being deflected and scan the scanning medium, a light shielding means is provided on the optical axis between the imaging optical system and the scanning medium. A scanning optical system featuring:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61201258A JPH0627902B2 (en) | 1986-08-29 | 1986-08-29 | Laser scanning optical system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61201258A JPH0627902B2 (en) | 1986-08-29 | 1986-08-29 | Laser scanning optical system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6358315A true JPS6358315A (en) | 1988-03-14 |
| JPH0627902B2 JPH0627902B2 (en) | 1994-04-13 |
Family
ID=16437958
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61201258A Expired - Lifetime JPH0627902B2 (en) | 1986-08-29 | 1986-08-29 | Laser scanning optical system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0627902B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8559053B2 (en) | 2010-03-24 | 2013-10-15 | Ricoh Company, Limited | Optical scanning device and image forming device |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4845448B2 (en) * | 2004-08-05 | 2011-12-28 | キヤノン株式会社 | Optical scanning device |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5667816A (en) * | 1979-10-29 | 1981-06-08 | Xerox Corp | Spot scanning device |
| JPS6195314A (en) * | 1984-10-16 | 1986-05-14 | Fuji Photo Film Co Ltd | Optical scanner |
-
1986
- 1986-08-29 JP JP61201258A patent/JPH0627902B2/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5667816A (en) * | 1979-10-29 | 1981-06-08 | Xerox Corp | Spot scanning device |
| JPS6195314A (en) * | 1984-10-16 | 1986-05-14 | Fuji Photo Film Co Ltd | Optical scanner |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8559053B2 (en) | 2010-03-24 | 2013-10-15 | Ricoh Company, Limited | Optical scanning device and image forming device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0627902B2 (en) | 1994-04-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH07110451A (en) | Optical scanner | |
| JPH0387731A (en) | Image display device | |
| WO1988007698A1 (en) | Optical scanner | |
| JPS5868014A (en) | Scanning optical system for removing ghost image | |
| JPH02115814A (en) | Light beam scanning device | |
| JPH0776745B2 (en) | Microspectrophotometer | |
| JP2722269B2 (en) | Scanning optical system | |
| KR100335624B1 (en) | Laser beam scanning apparatus | |
| JPH05308483A (en) | Optical scanner and printer | |
| JPS6358315A (en) | Laser scanning optical system | |
| US4234240A (en) | Optical scanning system with unwanted reflections controlled | |
| KR20060021315A (en) | Fresnel lens, projection screen, corresponding projection device and system | |
| JPH112769A (en) | Optical scanner | |
| JPS62269925A (en) | Light beam scanning optical system | |
| JPH06308379A (en) | Focus detector | |
| KR20050017859A (en) | Laser scanning unit | |
| JPH06148558A (en) | Light deflector device | |
| JPH04277643A (en) | Optical inspection apparatus for transparent substrate | |
| JP2002023088A (en) | Scanning optical system | |
| JPH02254410A (en) | Laser scanning optical system | |
| JP3206947B2 (en) | Scanning optical device | |
| JPH11311748A (en) | Optical scanning device | |
| JPH05127119A (en) | Scanning optical system removing ghost image | |
| JPH08136861A (en) | Super-resolution scanning optical system | |
| JPH0248630A (en) | Optical scanner |