JPS62148914A - Video projector lens - Google Patents

Video projector lens

Info

Publication number
JPS62148914A
JPS62148914A JP28983985A JP28983985A JPS62148914A JP S62148914 A JPS62148914 A JP S62148914A JP 28983985 A JP28983985 A JP 28983985A JP 28983985 A JP28983985 A JP 28983985A JP S62148914 A JPS62148914 A JP S62148914A
Authority
JP
Japan
Prior art keywords
lens barrel
barrel
lens
magnification
video projector
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
JP28983985A
Other languages
Japanese (ja)
Inventor
Mikio Sakai
幹雄 酒井
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.)
Canon Inc
Original Assignee
Canon Inc
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 Canon Inc filed Critical Canon Inc
Priority to JP28983985A priority Critical patent/JPS62148914A/en
Publication of JPS62148914A publication Critical patent/JPS62148914A/en
Pending legal-status Critical Current

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Abstract

PURPOSE:To perform operations of magnification adjustment and aberration compensation quickly and easily by providing a magnification display device for an extent of relative movement of the third barrel to the second barrel in the fitting part between the second and third barrels. CONSTITUTION:In a video projector lens, a magnification display device 11 is formed for an extent of relative movement of the third barrel to the second barrel in the fitting part between the second and third barrels 2 and 3, and this device 11 consists of a magnification scale 5 formed on the outside peripheral surface of the second barrel 2 and an index 4 projected onto the scale 5 from the end face of the third barrel 3. The magnification scale 5 is graduated in the peripheral direction correspondingly to the extent of movement of the barrel 3 in the peripheral direction, and the index 4 is projected from the end face of the barrel 3 in parallel with the axial line of the barrel. When the barrel 3 is rotated, the extent of relative movement in the axial direction of the barrel 3 to the barrel 2 is detected by the display device 11; and the barrel 3 is moved accurately by a prescribed extent with respect to the barrel 2 in accordance with a magnification selected on the display device 11.

Description

【発明の詳細な説明】 〔発明の利用分野〕 この発明はビデオプロジェクタ−に関し、特に倍率調整
と収差補正の操作を迅速且つ容易に行うことのできる改
良されたビデオプロジェクタ−レンズに関するものであ
る。
DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a video projector, and more particularly to an improved video projector lens that allows magnification adjustment and aberration correction to be performed quickly and easily.

〔発明の背景〕[Background of the invention]

第4図は本発明の基礎とするビデオプロジェクタ−レン
ズを示したものである。同図において、1は被投影物(
この場合はブラクン管9の画面)に対面する第一のレン
ズ6を保持してビデオプロジェクター等の機枠とともに
軸方向移動不能に構成されている第一の鏡筒であシ、こ
の第一の鏡筒1の他端部内周面のねじ部には第二の鏡筒
2の−端部の外周面に形成されたねじ部が噛み合ってい
る。第二の鏡筒2は一対の第二のレンズ7を保持してお
勺、第一の鏡筒1に対して相対的に軸方向移動しうるよ
うになっている。第二の鏡筒2の他端部の外周面にもね
じ部が設けられておシ、このねじ部には収差補正用の第
三の鏡筒3の一端部内周面に形成されたねじ部が噛み合
っている。第三の鏡筒3はスクリーン10等の投影面に
面する第三のレンズ8を保持しており、第二の鏡筒2に
対して軸線方向に相対的に移動しうるようになっている
。なおスクリーン10は便宜上、近接して描いているが
、実際には離されて置かれている。
FIG. 4 shows a video projector lens on which the present invention is based. In the figure, 1 is the projected object (
In this case, a first lens barrel that holds the first lens 6 facing the screen of the Brakun tube 9 and is configured to be immovable in the axial direction together with the frame of a video projector or the like is used. A threaded portion formed on the outer circumferential surface of the negative end of the second lens barrel 2 is engaged with a threaded portion on the inner circumferential surface of the other end of the lens barrel 1 . The second lens barrel 2 holds a pair of second lenses 7 and is movable in the axial direction relative to the first lens barrel 1. A threaded portion is also provided on the outer circumferential surface of the other end of the second lens barrel 2, and this threaded portion is provided with a threaded portion formed on the inner circumferential surface of one end of the third lens barrel 3 for aberration correction. are engaged. The third lens barrel 3 holds a third lens 8 facing a projection surface such as a screen 10, and is movable relative to the second lens barrel 2 in the axial direction. . Note that although the screens 10 are depicted close together for convenience, they are actually placed apart.

前記の如きビデオグロ・ゾエクターレンズを用いる時に
は次のような操作を行ってい之。
When using the above-mentioned Videoglo Zoector lens, the following operations are performed.

(1)マず、投影倍率を適正倍率にするためにフォーカ
シングを行う。このため第二の鏡筒2を回転させて鏡筒
2を鏡筒1に対して軸線方向に前後動させることによυ
レンズ7.8をスクリーン10に対して適正位置に位置
決めする。
(1) First, focusing is performed to make the projection magnification an appropriate magnification. Therefore, by rotating the second lens barrel 2 and moving the lens barrel 2 back and forth in the axial direction with respect to the lens barrel 1, υ
Position the lens 7.8 in the proper position relative to the screen 10.

(iD  次にスクリーン10上に投影された像を児な
がら第三の鏡筒3を回転させて該鏡筒3を第二の鏡筒2
に対して、相対的に軸方向移動させることによシ、レン
ズ7とレンズ8との間隔を変えて収差補正を行う。
(iD) Next, rotate the third lens barrel 3 while observing the image projected on the screen 10, and transfer the third lens barrel 3 to the second lens barrel 2.
By moving the lenses 7 and 8 in the axial direction relative to each other, the distance between the lenses 7 and 8 is changed to correct aberrations.

(iii)  収差補正操作によ多倍率が変化した場合
、再び第二の鏡筒2を回転操作して倍率を再調整した後
、再び第三の鏡筒3を回転操作して収差補正を行う。
(iii) If the multiple magnification changes due to the aberration correction operation, rotate the second lens barrel 2 again to readjust the magnification, and then rotate the third lens barrel 3 again to correct the aberrations. .

従って、ビデオプロジェクターレンズの調整には熟練と
時間を要し、甚だ面倒であった。
Therefore, adjusting the video projector lens requires skill and time, and is extremely troublesome.

それ故、カメラレンズ合焦においては、このような面倒
な操作を少くするためにフローティング方式が採用され
ているが、フローティング方式の場合、會−及びキー溝
の加工が必要となるため、加工コストが高くなるという
欠点があった。
Therefore, in camera lens focusing, a floating method is adopted in order to reduce such troublesome operations, but in the case of a floating method, processing of the frame and keyway is required, which increases the processing cost. The disadvantage was that it was expensive.

〔発明の目的〕[Purpose of the invention]

この発明の目的は、前記の如き面倒な操作を要すること
なく迅速且つ容易にセツティングを行うことができると
ともに著るしいコスト上昇を招くことのない、改良され
たビデオプロジェクタ−レンズを提供することである。
An object of the present invention is to provide an improved video projector lens that can be quickly and easily set up without requiring the above-mentioned troublesome operations, and without causing a significant increase in cost. It is.

〔発明の概要〕[Summary of the invention]

この発明による改良されたビデオプロジェクターレンズ
の特徴は、第二の鏡筒と第三の鏡筒との嵌合部分におい
て両者の相対移動量に対応する倍率表示手段を設けたこ
とである。すなわち、本発明のビデオプロジェクタ−レ
ンズでは、投影倍率又は投影距離に対応した収差補正を
該倍率表示手段によって合わせておいた後、フォーカシ
ングを行えば、それ以上の繰シ返し操作を要することな
く、その投影倍率における最適な像を得ることができる
A feature of the improved video projector lens according to the present invention is that a magnification display means corresponding to the amount of relative movement between the second lens barrel and the third lens barrel is provided at the fitting portion of the second lens barrel and the third lens barrel. That is, in the video projector lens of the present invention, if focusing is performed after aberration correction corresponding to the projection magnification or projection distance is adjusted by the magnification display means, no further repeated operations are required. An optimal image at that projection magnification can be obtained.

〔発明の実施例〕[Embodiments of the invention]

第1図乃至第3図を参照して本発明の詳細な説明する。 The present invention will be described in detail with reference to FIGS. 1 to 3.

なお、第1図乃至第3図において第4図と同一符号で示
された部分は前述のビデオプロジェクターレンズと同一
の部分であるから、この同一部分についての説明を省略
する。
Note that in FIGS. 1 to 3, the parts indicated by the same reference numerals as in FIG. 4 are the same parts as the above-mentioned video projector lens, so a description of these same parts will be omitted.

第1図は本発明の第一実施例のビデオグロジエクターレ
ンズを示したものである。本発明のビデオプロジェクタ
ーレンズでは、同図に示されるように、第二の鏡筒2と
第三の鏡筒3との嵌合部分において両鏡筒の相対移動量
に対応する倍率表示装置11が形成されておシ、この実
施例では該表示装置11が、第二の鏡筒2の外周面に形
成した倍率目盛5と、第三の鏡筒3の端面から該目盛5
上に突出させた指針4とで構成されている。倍率目盛5
は鏡筒3の周方向の移動量に対応するように円周方向に
沿って刻まれておシ、指針4は鏡筒の軸線方向と平行に
鏡筒3の端面から突出している。従って、鏡筒3を回転
させれば、該表示装置11によって鏡筒3の鏡筒2に対
する相対的軸方向移動量を知ることができ、また、該表
示装置11によシ選抜した倍率に応じて鏡筒3を鏡筒2
に対して所定量だけ正確に移動させることができる。
FIG. 1 shows a video glossier lens according to a first embodiment of the present invention. In the video projector lens of the present invention, as shown in the figure, a magnification display device 11 corresponding to the relative movement amount of the second lens barrel 2 and the third lens barrel 3 is provided at the fitting portion of the second lens barrel 2 and the third lens barrel 3. In this embodiment, the display device 11 includes a magnification scale 5 formed on the outer peripheral surface of the second lens barrel 2 and a scale 5 formed on the end surface of the third lens barrel 3.
It is composed of a pointer 4 that projects upward. Magnification scale 5
is carved along the circumferential direction so as to correspond to the amount of movement of the lens barrel 3 in the circumferential direction, and the pointer 4 protrudes from the end surface of the lens barrel 3 in parallel to the axial direction of the lens barrel. Therefore, by rotating the lens barrel 3, the relative axial movement amount of the lens barrel 3 with respect to the lens barrel 2 can be known from the display device 11. and move lens barrel 3 to lens barrel 2.
can be accurately moved by a predetermined amount.

第1図のビデオプロジェクターレンズを使用して倍率調
整と収差補正を行う時には次のような操作を行えばよい
When performing magnification adjustment and aberration correction using the video projector lens shown in FIG. 1, the following operations may be performed.

(、)  まず、鏡筒3を回転させて指針4が20倍。(,) First, rotate the lens barrel 3 and the pointer 4 will be magnified by 20 times.

30倍、40倍の内、所望の倍率目盛5の上にくるよう
に操作する。これによシ、所定倍率に応じてレンズ7と
レンズ8との間隔が設定される。
Operate so that the desired magnification scale 5 is selected from 30x and 40x. Accordingly, the distance between the lenses 7 and 8 is set according to the predetermined magnification.

(b)  次にスクリーン10上の投影像を見なから鏡
筒2を回転させる(鏡筒3も鏡筒2と一体に回転するの
で両者の間には相対運動は生じ々い)と、鏡筒2が鏡筒
1に対して相対的に軸方向移動するのでピント合せを行
うことができる。この場合、レンズ7とレンズ8との間
隔t(、倍率に応じて設計的に定まった間隔)は(lL
)の操作で既に決っているので(b)の操作によってt
の値が変ってくることはない。従って、ピント合せ終了
後に収差補正操作を再び行う必要はない。
(b) Next, rotate the lens barrel 2 without looking at the projected image on the screen 10 (because the lens barrel 3 also rotates together with the lens barrel 2, there will be no relative movement between the two). Since the barrel 2 moves in the axial direction relative to the lens barrel 1, focusing can be performed. In this case, the distance t between the lenses 7 and 8 (the distance determined by design according to the magnification) is (lL
) has already been determined by the operation (b), so t is determined by the operation (b).
The value of never changes. Therefore, there is no need to perform the aberration correction operation again after focusing.

第2図は本発明の第二実施例であυ、第一実施例の一部
を変形した実施例を示したものである。
FIG. 2 shows a second embodiment of the present invention, which is a partially modified version of the first embodiment.

この実施例では、倍率表示装?f11が、鏡筒2の外周
面に軸方向に沿って刻まれた倍率目盛5Aと、鏡筒3の
端面3Aとで構成されている。倍率目盛5Aは鏡筒2の
軸方向に沿って設けられた目盛であるため、鏡筒2に対
する鏡筒3の相対的軸方向移動i:(もしくは相対的軸
方向位置)が倍率目盛5Aとなっている。この実施例で
は第1図の実施例よ)も目盛の数を減らすことができる
。また、鏡筒3の端面3Aが指針4の代シとな名ので指
針4を設ける必要がない。
In this example, the magnification display device? f11 is composed of a magnification scale 5A carved along the axial direction on the outer peripheral surface of the lens barrel 2, and an end surface 3A of the lens barrel 3. Since the magnification scale 5A is a scale provided along the axial direction of the lens barrel 2, the relative axial movement i: (or relative axial position) of the lens barrel 3 with respect to the lens barrel 2 becomes the magnification scale 5A. ing. In this embodiment, the number of graduations can also be reduced (as in the embodiment of FIG. 1). Further, since the end surface 3A of the lens barrel 3 serves as a pointer 4, there is no need to provide the pointer 4.

なお、操作方法は第1図の実施例のものと全く同じであ
るから説明を省略する。
Note that the operating method is exactly the same as that of the embodiment shown in FIG. 1, so a description thereof will be omitted.

第3図は本発明の第三実施例を示したものである。この
実施例では該倍率表示装置11が、鏡筒3の周面に貫設
した長溝3aと、該長溝3aKaって鏡筒3の外周面に
つけられた倍率目盛3bと、鏡筒2の外周面に突設され
るとともに該長溝3a内に相対摺動可能に挿入されてい
る指標ビン2aとで構成されている。また、鏡筒2と鏡
筒3とはねじ嵌合ではなく、通常の平滑円筒面嵌合とな
っている。従って、鏡筒3は鏡筒2に対して該長溝3a
の長手方向に相対移動することができ、両鏡筒の結合は
指標ビン2aと長溝3aとによるぎン結合となっている
FIG. 3 shows a third embodiment of the present invention. In this embodiment, the magnification display device 11 includes a long groove 3a penetrating the peripheral surface of the lens barrel 3, a magnification scale 3b attached to the outer peripheral surface of the lens barrel 3 by the long groove 3aKa, and a magnification scale 3b on the outer peripheral surface of the lens barrel 2. The index bin 2a is provided in a protruding manner and inserted into the long groove 3a so as to be relatively slidable therein. Further, the lens barrel 2 and the lens barrel 3 are not screw-fitted, but are fitted with normal smooth cylindrical surfaces. Therefore, the lens barrel 3 is attached to the long groove 3a with respect to the lens barrel 2.
can be moved relative to each other in the longitudinal direction, and the two lens barrels are connected by a pin connection using an index pin 2a and a long groove 3a.

指標ビン28の頂面には倍率目盛3bの線と平行な指標
線が刻設されていて、該指標線を倍率目盛3bに合わせ
ることによって倍率目盛を容易に読取ることができる。
An index line parallel to the line of the magnification scale 3b is engraved on the top surface of the index bin 28, and the magnification scale can be easily read by aligning the index line with the magnification scale 3b.

第3図の実施例のビデオプロジェクタ−レンズでは、鏡
筒3を軸方向に鏡筒2から引き離すように引くと、鏡筒
3は長溝3aに沿うように回転しつつ鏡筒2に対して軸
方向に移動するので、指標ビン2a上の指標線が所定の
倍率目盛3bに合う位置まで鏡筒3を移動させた後、鏡
筒2を回転してレンズ6とレン、e7とを所定間隔だけ
離せばよい。
In the video projector lens of the embodiment shown in FIG. 3, when the lens barrel 3 is pulled away from the lens barrel 2 in the axial direction, the lens barrel 3 rotates along the long groove 3a and axially relative to the lens barrel 2. After moving the lens barrel 3 to a position where the index line on the index bin 2a matches the predetermined magnification scale 3b, rotate the lens barrel 2 and align the lens 6, lens, and e7 by a predetermined distance. Just let go.

〔発明の効果〕〔Effect of the invention〕

以上に説明したように、本発明によれば、倍率調整と収
差補正の操作を迅速且つ容易に行うことができるととも
に製造コストの著るしい高騰を招くことのない、改良さ
れたぎデオプロジェクターレンズが提供される。
As explained above, according to the present invention, an improved deo-projector lens that allows magnification adjustment and aberration correction operations to be performed quickly and easily, and does not cause a significant increase in manufacturing costs. is provided.

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

第1図及び第2図は本発明による改良されたビデオプロ
ジェクタ−レンズの第一実施例と第二実雄側を示した図
であって、同図において(IL)は縦断面図、(b)は
(、)におけるb−b矢視図、第3図(、)は本発明の
第三実施例の縦断面図、第3図(b)は平面図、第4図
は本発明の基礎となるビデオプロジェクタ−レンズの縦
断面図である。 l・・・第一の鏡筒、    2・・・第二の鏡筒、3
・・・第三の鏡筒、    4・・・指針、5.5A、
3b・・・倍率目盛、 6・・・第一のレンズ、   7・・・第二のレンズ、
8・・・第三のレンズ、   9・・・ブラウン管、1
0・・・スクリーン、   11・・・倍率表示装置。
1 and 2 are diagrams showing a first embodiment and a second real side of the improved video projector lens according to the present invention, in which (IL) is a longitudinal sectional view, and (b) is a longitudinal sectional view. 3(,) is a vertical cross-sectional view of the third embodiment of the present invention, FIG. 3(b) is a plan view, and FIG. 4 is a diagram showing the basis of the present invention. FIG. 2 is a longitudinal cross-sectional view of a video projector lens. l...first lens barrel, 2...second lens barrel, 3
...Third lens barrel, 4...Pointer, 5.5A,
3b...Magnification scale, 6...First lens, 7...Second lens,
8...Third lens, 9...Cathode ray tube, 1
0...Screen, 11...Magnification display device.

Claims (3)

【特許請求の範囲】[Claims] (1)被投影物に対面する第一のレンズを保持した第一
の鏡筒と、第二のレンズを保持するとともに前記第一の
鏡筒に対して軸線方向に相対移動しうる第二の鏡筒と、
スクリーン等の投影面に面する第三のレンズを保持する
とともに前記第二の鏡筒に対して軸線方向に相対移動し
うる収差補正用の第三の鏡筒と、を有したビデオプロジ
ェクターレンズにおいて、 前記第二の鏡筒と前記第三の鏡筒との嵌合部分において
前記第二の鏡筒に対する前記第三の鏡筒の相対移動量に
対応する倍率表示装置を設けたことを特徴とするビデオ
プロジェクターレンズ。
(1) A first lens barrel holding a first lens facing the object to be projected, and a second lens barrel holding a second lens and movable relative to the first lens barrel in the axial direction. lens barrel and
A video projector lens comprising: a third lens barrel for aberration correction that holds a third lens facing a projection surface such as a screen and is movable relative to the second lens barrel in the axial direction; , characterized in that a magnification display device corresponding to the amount of relative movement of the third lens barrel with respect to the second lens barrel is provided at the fitting portion of the second lens barrel and the third lens barrel. video projector lens.
(2)前記倍率表示装置が前記第二の鏡筒の外周面に設
けられている目盛を含んでいることを特徴とする、特許
請求の範囲第1項のビデオプロジェクターレンズ。
(2) The video projector lens according to claim 1, wherein the magnification display device includes a scale provided on the outer peripheral surface of the second lens barrel.
(3)前記倍率表示装置が、前記第三の鏡筒の外周面に
貫設された長溝と、前記長溝に沿って設けられた目盛と
、前記第二の鏡筒に突設されるとともに前記長溝に沿っ
て移動しうる指標と、から構成されていることを特徴と
する特許請求の範囲第1項のビデオプロジェクターレン
ズ。
(3) The magnification display device includes a long groove penetrating the outer peripheral surface of the third lens barrel, a scale provided along the long groove, and a scale protruding from the second lens barrel. 2. The video projector lens according to claim 1, further comprising: an index movable along a long groove.
JP28983985A 1985-12-23 1985-12-23 Video projector lens Pending JPS62148914A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP28983985A JPS62148914A (en) 1985-12-23 1985-12-23 Video projector lens

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP28983985A JPS62148914A (en) 1985-12-23 1985-12-23 Video projector lens

Publications (1)

Publication Number Publication Date
JPS62148914A true JPS62148914A (en) 1987-07-02

Family

ID=17748436

Family Applications (1)

Application Number Title Priority Date Filing Date
JP28983985A Pending JPS62148914A (en) 1985-12-23 1985-12-23 Video projector lens

Country Status (1)

Country Link
JP (1) JPS62148914A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06175019A (en) * 1992-10-28 1994-06-24 Samsung Electron Co Ltd Back-projecting type tv projecting lens system
JPH06208054A (en) * 1992-10-28 1994-07-26 Samsung Electron Co Ltd Projection lens system for rear projection system tv
JPH06258575A (en) * 1992-06-26 1994-09-16 Mitsubishi Electric Corp Projection lens
WO2013080953A1 (en) * 2011-12-01 2013-06-06 三菱電機株式会社 Projection optical system and projection image display apparatus
WO2014171136A1 (en) * 2013-04-18 2014-10-23 パナソニック株式会社 Projection-type video display apparatus

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06258575A (en) * 1992-06-26 1994-09-16 Mitsubishi Electric Corp Projection lens
JPH06175019A (en) * 1992-10-28 1994-06-24 Samsung Electron Co Ltd Back-projecting type tv projecting lens system
JPH06208054A (en) * 1992-10-28 1994-07-26 Samsung Electron Co Ltd Projection lens system for rear projection system tv
WO2013080953A1 (en) * 2011-12-01 2013-06-06 三菱電機株式会社 Projection optical system and projection image display apparatus
US9261758B2 (en) 2011-12-01 2016-02-16 Mitsubishi Electric Corporation Projection optical system and projection-type image display apparatus
WO2014171136A1 (en) * 2013-04-18 2014-10-23 パナソニック株式会社 Projection-type video display apparatus

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