JP4329430B2

JP4329430B2 - Lens apparatus and assembly method

Info

Publication number: JP4329430B2
Application number: JP2003195592A
Authority: JP
Inventors: 雄俊采女; 宏人荻山; 聡今井; 正憲林; 達也山崎
Original assignee: Sony Corp
Current assignee: Sony Corp
Priority date: 2003-07-11
Filing date: 2003-07-11
Publication date: 2009-09-09
Anticipated expiration: 2023-07-11
Also published as: JP2005031329A

Description

【０００１】
【発明の属する技術分野】
本発明はレンズ装置および組立方法に関するものである。
【０００２】
【従来の技術】
複数のレンズをレンズ取付部に固定したレンズ装置がある。このようなレンズ装置においては、レンズをレンズ取付部に収容固定する際に、各レンズ間における光軸のずれを調整して所定の偏芯精度を得るため、いわゆる調芯を行なう必要がある。
従来、調芯を行なうためには、レンズ取付部側に調芯を行なうための専用部品を設けたり、レンズ取付部の外側から治具を用いてレンズを移動させて調芯を行なっている（例えば特許文献１参照）。
【０００３】
【特許文献１】
特開平１０−２３２３３５号公報
【０００４】
【発明が解決しようとする課題】
しかしながら、前者のようにレンズ取付部側に調芯を行なうための専用部品を設ける場合には、部品点数が増加するとともに、レンズ装置の占有スペースが大きくなる欠点がある。
また、後者のようにレンズ取付部の外側から治具を用いてレンズを移動させて調芯を行なう場合には、レンズを移動させるためのクリアランスをレンズとレンズ取付部の間に確保する必要があり、やはりレンズ装置の占有スペースが大きくなる欠点がある。
本発明は、このような事情に鑑みてなされ、その目的とするところは、部品点数を削減するとともに、小型化を図る上で有利なレンズ装置および組立方法を提供することにある。
【０００５】
【課題を解決するための手段】
本発明のレンズ装置は前記目的を達成するために、レンズ取付部と、前記レンズ取付部に取付けられるレンズとを備え、前記レンズ取付部は、前記レンズの外周面が載置される環状の載置面と、前記レンズの外径よりも大きな内径を有して前記載置面の外周から起立する環状の起立壁と、前記起立壁の対向する箇所に設けられた２つのレンズ移動用欠部とを有するレンズ装置であって、前記２つのレンズ移動用欠部は、それらレンズ移動用欠部を介してレンズ移動爪が前記載置面の半径方向において前記起立壁の外側から内側に移動できるように構成され、前記２つのレンズ移動用欠部のうちの一方のレンズ移動用欠部の両側に臨む各起立壁の内周面箇所にそれぞれ突出部が設けられ、前記突出部が設けられていない前記レンズ移動用欠部から前記レンズ移動爪が前記レンズの外周端面に当たることで他方の前記レンズ移動用欠部に向けて前記レンズが移動されることにより、前記レンズの外周端面が各突出部に当接した状態で、前記各突出部は、レンズの外周端面と各突出部との当接箇所とを結んだ想像線に対して直交する想像線のうち前記レンズの中心を通る中心線が、前記レンズ取付部の中心軸上を通るように形成されていることを特徴とする。
そのため、２つのレンズ移動用欠部のうち、突出部が設けられていないレンズ移動用欠部からレンズ移動爪をレンズの外周端面に当てて他方のレンズ移動用欠部に向けてレンズを移動させ、レンズの外周端面を各突出部に当接させることで、レンズの外周端面と各突出部との当接箇所とを結んだ想像線に対して直交する想像線のうち前記レンズの中心を通る中心線が、前記レンズ取付部の中心軸上を通るように調整される。
【０００６】
また、本発明のレンズ装置の組立方法は、レンズの外周面が載置される環状の載置面と、前記載置面の外周から起立する環状の起立壁と、前記起立壁の対向する箇所に設けられた２つのレンズ移動用欠部とを有するレンズ取付部にレンズを取付ける方法であって、前記２つのレンズ移動用欠部のうちの一方のレンズ移動用欠部に臨む両側の起立壁の内周面箇所に、該起立壁の半径方向の内側に突出する突出部をそれぞれ設け、前記起立壁の内側で前記載置面上にレンズ外周面を載置し、前記２つのレンズ移動用欠部のうち、前記突出部が設けられていない前記レンズ移動用欠部からレンズ移動爪をレンズの外周端面に当てて他方の前記レンズ移動用欠部に向けてレンズを移動させ、前記レンズの外周端面を各突出部に当接させることで、レンズの外周端面と各突出部との当接箇所とを結んだ想像線に対して直交する想像線のうち前記レンズの中心を通る中心線が、前記レンズ取付部の中心軸上を通るように調整し、その後、前記突出部が設けられた側のレンズ移動用欠部からレンズ移動爪をレンズの外周端面に当てることにより前記レンズの外周端面を２つの前記レンズ移動爪で挟持して前記レンズを前記レンズ取付部の中心軸と直交する面に沿って移動させて調芯を行い、前記調芯がなされた後、前記レンズを前記レンズ取付部に固定することを特徴とする。
そのため、レンズの外周端面が各突出部に当接されることにより、レンズは該レンズの中心を通る中心線が、レンズ取付部の中心軸上を通る状態となるので、中心軸を挟んで対向する２つのレンズ移動爪に対してレンズが大きくずれることが防止でき、各レンズ移動爪によるレンズの挟持が安定しかつ確実に行われる。
【０００７】
【発明の実施の形態】
次に、本発明の実施の形態について図面を参照して説明する。
図１は本実施の形態のレンズ装置の構成を示す縦断面図、図２はレンズ装置の斜視図、図３乃至図６はレンズ装置における調芯動作の説明図、図７はレンズ装置と治具の構成を示す説明図である。
図１に示すように、レンズ装置２は鏡筒４を備え、鏡筒４には第１レンズ取付部１２と第２レンズ取付け部１４とが設けられ、これら第１、第２レンズ取付部１２、１４に第１、第２レンズ１６、１８が取り付けられ、さらに鏡筒４にはカムピン６が突設されている。
カムピン６は、レンズ装置２が不図示の光学系に組み込まれた場合に前記光学系に設けられたカム溝に係合されることでレンズ装置２を移動させるために設けられているものであり、本実施の形態では３つ設けられている。
第１、第２レンズ１６、１８は、それぞれ光軸方向から見て外周端面が正円をなすように形成されている。
【０００８】
図１に示すように、第１レンズ取付部１２は、第１レンズ１６の外周面が載置される環状の第１載置面１２０２と、第１レンズ１６の外径に対応した内径を有して第１載置面１２０２の外周から起立する環状の第１起立壁１２０４とを有している。
第１レンズ１６は、一方の外周面を第１載置面１２０２に載置し、外周端面を第１起立壁１２０４に嵌合することで配設されている。
第１レンズ１６が第１起立壁１２０４に嵌合された状態で第１レンズ取付部１２の中心軸、すなわち鏡筒４の中心軸Ｚに対して第１レンズ１６の中心、すなわち光軸がほぼ一致するように形成されているが、第１起立壁１２０４の寸法精度のばらつきや、第１レンズ１６の加工精度のばらつきによって第１レンズ１６の光軸と中心軸Ｚとの間には誤差が生じる。
【０００９】
図２、図３に示すように、第２レンズ取付部１４は、第１起立壁１２０４の上端に設けられ第２レンズ１８の外周面が載置される環状の第２載置面１４０２と、第２レンズ１８の外径よりも大きな内径を有して第２載置面１４０２の外周から起立する環状の第２起立壁１４０４と、第２起立壁１４０４の対向する箇所に設けられた２つのレンズ移動用欠部１４０６とを有している。
２つのレンズ移動用欠部１４０６は、後述するレンズ移動爪２０Ａ、２０Ｂが第２起立壁１４０４の外側から内側に移動できるように構成されている。
２つのレンズ移動用欠部１４０６のうちの一方のレンズ移動用欠部１４０６の両側に臨む各第２起立壁１４０４の内周面箇所にそれぞれ突出部１４０８が設けられている。
突出部１４０８は、第２起立壁１４０４の内周面の半径方向内側に突出し、レンズ移動用欠部１４０６を挟んで対称な形状で形成されている。
図４に示すように、各突出部１４０８は、第２レンズ１８の外周端面が各突出部１４０８に当接した状態で、第２レンズ１８の外周端面と各突出部１４０８との当接箇所とを結んだ想像線Ｘに対して直交する想像線Ｙのうち第２レンズ１８の中心を通る中心線Ｙ１が、第２レンズ取付部１４の中心軸、すなわち鏡筒４の中心軸Ｚ上を通るように形成されている。
【００１０】
次に、レンズ装置２を組み立てる際に用いる治具について説明する。
図３、図７に示すように、治具は、レンズ装置２の鏡筒４を移動不能に固定する固定機構（不図示）と、２つのレンズ移動爪２０Ａ、２０Ｂとを有している。
２つのレンズ移動爪２０Ａ、２０Ｂは、前記固定機構によって固定された鏡筒４の中心軸Ｚを挟んで対向して設けられ、各レンズ移動爪２０Ａ、２０Ｂには、第２載置面１４０２上に載置された第２レンズ１８の外周端面に当接する当接面２００２が形成されている。
各当接面２００２は、図７に示すように、第２レンズ１８の外周端面に当接したときに、第２レンズ１８の半径方向（第２起立壁１４０４の内周面に当接する方向）および厚さ方向（第２載置面１４０２に当接する方向）の双方の方向に力が作用するように中心軸Ｚに対して傾斜して設けられている。
また、図３に示すように、中心軸Ｚ方向から見た場合、突出部１４０８と反対側に位置する一方のレンズ移動爪２０Ａの当接面２００２は単一の平坦面で構成され、突出部１２１２と同じ側に位置する他方のレンズ移動爪２０Ｂの当接面２００２は第２レンズ１８の外周端面を挟むように２つの平坦面がＶ字状に交差して構成されている。
また、各レンズ移動爪２０Ａ、２０Ｂは、図４に示すように、第２レンズ保持部１４の中心軸Ｚを挟んで互いに接離する方向に独立して移動できるように構成され、かつ、第２載置面１４０２上に載置された第２レンズ１８の外周端面を各当接面２００２で挟持した状態で第２レンズ１８を中心軸Ｚと直交する平面に沿って移動させることにより、第１レンズ１６の光軸に対して第２レンズ１８の光軸を合致させて調芯を行うように構成されている。
また、本例では、レンズ移動爪２０Ａの平坦面からなる当接面２００２とレンズ移動爪２０Ｂの２つの平坦面からなる当接面２００２によって第２レンズ１８の外周端面が挟持されるので、第２レンズ１８を安定して挟持する上で有利であるが、レンズ移動爪２０Ａ、２０Ｂの当接面がそれぞれ１つの平坦面から構成されていてもよい。
なお、本実施の形態では、第２レンズ取付部１４、第２載置面１４０２、第２起立壁１４０４、第２レンズ１８のそれぞれによって、特許請求の範囲のレンズ取付部、載置面、起立壁、レンズのそれぞれが構成されている。
【００１１】
次に、レンズ装置２の組み立てについて説明する。
図１に示すように、第１レンズ１６は、第１レンズ１６の外周端面が第１起立壁１４０４に嵌合されているものとする。したがって、第１レンズ１６の光軸と第１取付部１４、すなわち鏡筒４の中心軸Ｚはほぼ一致した状態となっている。
このように第１レンズ１６が組み込まれた鏡筒４を前記治具の固定機構によって固定する。
そして、図１、図７（Ａ）に示すように、鏡筒４の一方の開口から第２レンズ１８を鏡筒１４の内方へ挿入し、第２レンズ１８の外周面を第２載置面１４０２に載置する。この際、各レンズ移動爪２０は、鏡筒４の外方に退避している。
次に、図３に示すように、一方のレンズ移動爪２０Ａのみをレンズ移動用欠部１４０６から鏡筒４の内側に向けて移動させ、当接面２００２を第２レンズ１８の外周端面に当接させ、第２レンズ１８を各突出部１４０８に向かって移動させる。
これにより、図４に示すように、第２レンズ１８の外周端面が各突出部１４０８に当接されると、第２レンズ１８は、前述したように第２レンズ１８の中心を通る中心線Ｙ１が、第２レンズ取付部１４の中心軸Ｚ上を通る状態となり、この状態で停止される。
そして、図５、図７（Ｂ）に示すように、他方のレンズ移動爪２０Ｂをレンズ移動用欠部１４０６から鏡筒４の内側に向けて移動させ、当接面２００２を第２レンズ１８の外周端面に当接させる。これにより、第２レンズ１８は、２つのレンズ移動爪２０Ａ、２０Ｂの当接面２００２で挟持される。
この状態で、図６に示すように、レンズ移動爪２０Ａ、２０Ｂによって第２レンズ１８を中心軸Ｚに直交する平面内で移動させ、第１レンズ１６の光軸に対して第２レンズ１８の光軸を一致させて調芯を行う。
具体的には、図１に示す中心軸Ｚ方向の一方（図１の上方）から第２レンズ１８に向けて調芯用のチャートの画像を示す光線を照射し、第２レンズ１８と第１レンズ１６によって結像されたチャートの画像を、図１に示す中心軸Ｚ方向の他方（図１の下方）に配置したＣＣＤなどの画像検出器で検出し、検出された前記チャートの画像をディスプレイなどに表示させる。
そして、前記ディスプレイに表示されるチャートの画像が正しく表示されるように、レンズ移動爪２０Ａ、２０Ｂによって第２レンズ１８を中心軸Ｚに直交する平面内で移動させる。前記チャートの画像が正しく表示されれば、第１レンズ１６の光軸に対して第２レンズ１８の光軸が一致したことになり調芯が完了する。このような調芯方法は従来公知のものである。
【００１２】
そして、前記調芯が完了した状態で、第２レンズ１８の外周端面と、第２載置面１４０２および起立壁１４０４との間の間隙に接着剤を充填して第２レンズ１８を第２レンズ取付部１４に接着する。本実施の形態では、接着剤として紫外線硬化型の接着剤を用い、充填した接着剤の部分に紫外線を照射することで接着剤を硬化させている。
【００１３】
本実施の形態によれば、第２レンズ１８の外周端面が各突出部１４０８に当接されることにより、第２レンズ１８は該第２レンズ１８の中心を通る中心線Ｙ１が、第２レンズ取付部１４の中心軸Ｚ上を通る状態となるので、中心軸Ｚを挟んで対向する２つのレンズ移動爪２０Ａ、２０Ｂに対して第２レンズ１８が大きくずれることが防止でき、各レンズ移動爪２０Ａ、２０Ｂによる第２レンズ１８の挟持を安定しかつ確実に行う上で有利となる。
例えば、図８に示す比較例のように、第２レンズ取付部１４に２つの突出部１４０８を設けない構成では次の欠点が生じる。すなわち、第２レンズ１８の中心が第２レンズ取付部１４の中心軸Ｚから大きくずれたときに、調芯のために第２レンズ１８を大きく移動させなくてはならないが、レンズ移動爪２０がレンズ移動用欠部１４０８と干渉してしまい調芯ができなくなってしまう。
特に、レンズ装置２の小型化に伴い、あるいは、鏡筒４にカムピン６などの部材を設けなくてはならず、レンズ移動用欠部１４０８を設けるスペースが限られている場合には上述のような不都合が生じる。
これに対して、本実施の形態のレンズ装置２ではこのような不具合を解消でき、レンズ装置２の小型化を図る上で有利である。
また、上述した比較例の場合には、第２レンズ１８の調芯を可能とするために、レンズ移動爪２０をレンズ移動用欠部１４０８に比較して相対的に小さい外形寸法とする必要があるため、レンズ移動爪２０の強度が低下してしまい撓みが発生してしまう。このため、第２レンズ１８の移動量にばらつきが生じてしまい高精度な調芯を行うことが困難となる。これに対して、本実施の形態のレンズ装置２では、レンズ移動爪２０の外形寸法を削減する必要がなく、レンズ移動爪２０の強度を確保できるので、第２レンズ１８の移動量のばらつきを抑制し、高精度な調芯を行う上で有利となる。
また、第２レンズ１８の外周端面が各突出部１４０８に当接されることにより、第２レンズ１８は該第２レンズ１８の中心を通る中心線Ｙ１が、第２レンズ取付部１４の中心軸Ｚ上を通る状態となる。これにより、第２レンズ１８はＸ方向における光軸位置が第１レンズ１６の光軸位置に対して極めて近い状態となっているため、調芯のために第２レンズ１８を移動する移動量が少なくてすみ、これにより調芯に要する時間を大幅に短縮でき、コストダウンを図る上で有利となる。
また、突出部１４０８は、第２レンズ取付け部１４の第２起立壁１４０４に突設するという極めて簡素な構成で済むため、部品点数の増加がなくコストアップが生じない。
【００１４】
なお、本実施の形態では、調芯するレンズが第２レンズ１８のみであったが、複数のレンズの調芯ができるように、鏡筒４の中心軸に沿って複数のレンズ取付部を設けてもよい。
また、本発明のレンズ装置は、フィルム式のカメラやデジタルカメラ、あるいはビデオカメラなどの各種撮像装置の光学系に適用可能である。また、光ディスク用の光ヘッド（光ピックアップ）の光学系にも適用可能である。
【００１５】
【発明の効果】
以上説明したように、本発明によれば、部品点数を削減するとともに、小型化を図る上で有利なレンズ装置および組立方法を提供することができる。
【図面の簡単な説明】
【図１】本実施の形態のレンズ装置の構成を示す縦断面図である。
【図２】レンズ装置の斜視図である。
【図３】レンズ装置における調芯動作の説明図である。
【図４】レンズ装置における調芯動作の説明図である。
【図５】レンズ装置における調芯動作の説明図である。
【図６】レンズ装置における調芯動作の説明図である。
【図７】レンズ装置と治具の構成を示す説明図である。
【図８】比較例としてのレンズ装置の構成を示す説明図である。
【符号の説明】
２……レンズ装置、４……鏡筒、１４……第２レンズ取付部、１８……第２レンズ、１４０２……第２載置面、１４０４……第２起立面、１４０６……レンズ移動用欠部、２０Ａ、２０Ｂ……レンズ移動爪。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens apparatus and an assembling method.
[0002]
[Prior art]
There is a lens device in which a plurality of lenses are fixed to a lens mounting portion. In such a lens apparatus, when the lens is housed and fixed in the lens mounting portion, so-called alignment needs to be performed in order to obtain a predetermined decentering accuracy by adjusting the deviation of the optical axis between the lenses.
Conventionally, in order to perform alignment, dedicated parts for alignment are provided on the lens mounting portion side, or the lens is moved from the outside of the lens mounting portion using a jig to perform alignment ( For example, see Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 10-232335
[Problems to be solved by the invention]
However, in the case of providing a dedicated component for aligning on the lens mounting portion side as in the former, there are disadvantages that the number of components increases and the occupied space of the lens device increases.
Further, when the centering is performed by moving the lens from the outside of the lens mounting portion using a jig as in the latter case, it is necessary to secure a clearance for moving the lens between the lens and the lens mounting portion. There is also a drawback that the occupied space of the lens apparatus becomes large.
The present invention has been made in view of such circumstances, and an object thereof is to provide a lens device and an assembling method that are advantageous in reducing the number of parts and reducing the size.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the lens device of the present invention includes a lens mounting portion and a lens mounted on the lens mounting portion, and the lens mounting portion is an annular mounting on which an outer peripheral surface of the lens is mounted. A mounting surface, an annular standing wall that has an inner diameter larger than the outer diameter of the lens and stands up from the outer periphery of the mounting surface, and two lens movement notches provided at locations facing the standing wall In the lens device, the lens moving claw can move from the outside to the inside of the standing wall in the radial direction of the mounting surface via the lens moving notch. is configured, wherein each protrusion on the inner peripheral surface portion of each upright walls facing both sides of one of the lens for moving the cut-out portions of the two lenses moving cutout portion is provided, the protrusion is provided Not the lens moving missing part By the lens moving pawl said toward the lens moving out portions other by hitting the outer peripheral end surface of the lens the lens is moved in a state in which the outer peripheral edge surface of the lens is brought into contact with the respective protrusion, said each protrusion center line passing through the center of the lens of the imaginary line perpendicular to the imaginary line connecting the contact portion between the outer peripheral end face and the projecting portions of the lenses, the center of the lens mounting portion It is formed so that it may pass on an axis | shaft.
Therefore, out of the two lens moving notches, the lens moving claw is applied to the outer peripheral end surface of the lens from the lens moving notched portion where the protrusion is not provided, and the lens is moved toward the other lens moving notch. By passing the outer peripheral end surface of the lens into contact with each protruding portion, the lens passes through the center of the imaginary line orthogonal to the imaginary line connecting the outer peripheral end surface of the lens and the contact portion between the protruding portions. A center line is adjusted so as to pass on the center axis of the lens mounting portion.
[0006]
The lens device assembling method of the present invention includes an annular mounting surface on which the outer peripheral surface of the lens is mounted, an annular standing wall that rises from the outer periphery of the mounting surface, and a place where the standing wall faces A lens mounting portion having two lens moving notches provided on the side, and standing walls on both sides facing one of the two lens moving notches Projecting portions projecting inward in the radial direction of the upstanding wall are provided at the inner peripheral surface portions of the lens, and the lens outer peripheral surface is placed on the mounting surface inside the upstanding wall, and the two lens moving surfaces are provided. Of the missing portions, the lens moving claw is applied to the outer peripheral end surface of the lens from the lens moving missing portion where the protruding portion is not provided, and the lens is moved toward the other lens moving missing portion. By bringing the outer peripheral end face into contact with each protrusion, the lens The center line passing through the center of the lens among the imaginary lines orthogonal to the imaginary line connecting the outer peripheral end surface of the lens and the contact portion of each protrusion is adjusted so as to pass on the central axis of the lens mounting portion. Thereafter, the lens moving claw is applied to the outer peripheral end surface of the lens from the lens moving notch portion on the side where the protruding portion is provided, so that the outer peripheral end surface of the lens is sandwiched between the two lens moving claws. Alignment is performed by moving along a plane orthogonal to the central axis of the lens mounting portion, and after the alignment, the lens is fixed to the lens mounting portion.
For this reason, when the outer peripheral end surface of the lens is brought into contact with each protrusion, the center line passing through the center of the lens passes through the center axis of the lens mounting portion. Thus, the lens can be prevented from being greatly displaced with respect to the two lens moving claws, and the lens can be held between the lens moving claws stably and reliably.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing the configuration of the lens apparatus of the present embodiment, FIG. 2 is a perspective view of the lens apparatus, FIGS. 3 to 6 are explanatory views of the alignment operation in the lens apparatus, and FIG. It is explanatory drawing which shows the structure of a tool.
As shown in FIG. 1, the lens apparatus 2 includes a lens barrel 4, and the lens barrel 4 is provided with a first lens attachment portion 12 and a second lens attachment portion 14, and these first and second lens attachment portions 12. , 14 are attached to the first and second lenses 16 , 18, and a cam pin 6 is projected from the lens barrel 4.
The cam pin 6 is provided to move the lens device 2 by being engaged with a cam groove provided in the optical system when the lens device 2 is incorporated in an optical system (not shown). In the present embodiment, three are provided.
The first and second lenses 16 and 18 are formed so that the outer peripheral end faces form a perfect circle when viewed from the optical axis direction.
[0008]
As shown in FIG. 1 , the first lens mounting portion 12 has an annular first placement surface 1202 on which the outer peripheral surface of the first lens 16 is placed, and an inner diameter corresponding to the outer diameter of the first lens 16. And an annular first standing wall 1204 that rises from the outer periphery of the first placement surface 1202.
The first lens 16 is disposed by placing one outer peripheral surface on the first placement surface 1202 and fitting the outer peripheral end surface to the first standing wall 1204.
When the first lens 16 is fitted to the first upright wall 1204, the center of the first lens 16, that is, the optical axis is substantially the same as the center axis of the first lens mounting portion 12, that is, the center axis Z of the lens barrel 4. Although they are formed so as to coincide, there is an error between the optical axis of the first lens 16 and the central axis Z due to variations in dimensional accuracy of the first standing wall 1204 and variations in processing accuracy of the first lens 16. Arise.
[0009]
As shown in FIGS. 2 and 3, the second lens mounting portion 14 is provided at the upper end of the first standing wall 1204 and has an annular second mounting surface 1402 on which the outer peripheral surface of the second lens 18 is mounted. An annular second standing wall 1404 that has an inner diameter larger than the outer diameter of the second lens 18 and stands up from the outer periphery of the second mounting surface 1402, and two portions that are provided at opposite positions of the second standing wall 1404. And a lens moving notch 1406.
The two lens moving notches 1406 are configured so that lens moving claws 20A and 20B, which will be described later, can move from the outside to the inside of the second standing wall 1404.
Protrusions 1408 are provided on the inner peripheral surface portions of the respective second upright walls 1404 facing both sides of one of the two lens moving notches 1406.
The protruding portion 1408 protrudes radially inward of the inner peripheral surface of the second standing wall 1404 and is formed in a symmetric shape with the lens moving notch portion 1406 interposed therebetween.
As shown in FIG. 4, each protrusion 1408 has a contact portion between the outer peripheral end surface of the second lens 18 and each protrusion 1408 in a state where the outer peripheral end surface of the second lens 18 is in contact with each protrusion 1408. A center line Y1 passing through the center of the second lens 18 out of an imaginary line Y orthogonal to the imaginary line X connecting the two passes through the central axis of the second lens mounting portion 14, that is, the central axis Z of the lens barrel 4. It is formed as follows.
[0010]
Next, a jig used when assembling the lens device 2 will be described.
As shown in FIGS. 3 and 7, the jig has a fixing mechanism (not shown) that immobilizes the lens barrel 4 of the lens device 2 and two lens moving claws 20 A and 20 B.
The two lens moving claws 20A and 20B are provided to face each other across the central axis Z of the lens barrel 4 fixed by the fixing mechanism. The lens moving claws 20A and 20B are provided on the second placement surface 1402 with each other. An abutment surface 2002 that abuts on the outer peripheral end surface of the second lens 18 placed on the lens is formed.
As shown in FIG. 7, each contact surface 2002 is in the radial direction of the second lens 18 (the direction contacting the inner peripheral surface of the second upright wall 1404) when contacting the outer peripheral end surface of the second lens 18. In addition, it is inclined with respect to the central axis Z so that a force acts in both directions in the thickness direction (direction in contact with the second placement surface 1402).
As shown in FIG. 3, when viewed from the central axis Z direction, the contact surface 2002 of one lens moving claw 20 A located on the opposite side to the protruding portion 1408 is configured by a single flat surface, and the protruding portion The abutment surface 2002 of the other lens moving claw 20B located on the same side as 1212 is formed by intersecting two flat surfaces in a V shape so as to sandwich the outer peripheral end surface of the second lens 18.
Further, as shown in FIG. 4, the lens moving claws 20 A and 20 B are configured to be able to move independently in a direction in which they are in contact with and away from each other across the central axis Z of the second lens holding portion 14. 2 by moving the second lens 18 along a plane perpendicular to the central axis Z in a state where the outer peripheral end surface of the second lens 18 placed on the placement surface 1402 is sandwiched between the contact surfaces 2002. Alignment is performed by matching the optical axis of the second lens 18 with the optical axis of the first lens 16.
Further, in this example, the outer peripheral end surface of the second lens 18 is sandwiched between the contact surface 2002 made of a flat surface of the lens moving claw 20A and the contact surface 2002 made of two flat surfaces of the lens moving claw 20B. Although it is advantageous for stably holding the two lenses 18, the contact surfaces of the lens moving claws 20 A and 20 B may each be composed of one flat surface.
In the present embodiment, each of the second lens mounting portion 14, the second mounting surface 1402, the second standing wall 1404, and the second lens 18 includes the lens mounting portion, the mounting surface, and the upright of the claims. Each of the wall and lens is configured.
[0011]
Next, assembly of the lens device 2 will be described.
As shown in FIG. 1, the first lens 16 is configured such that the outer peripheral end surface of the first lens 16 is fitted to the first standing wall 1404. Therefore, the optical axis of the first lens 16 and the first mounting portion 14, that is, the central axis Z of the lens barrel 4 are substantially coincident.
Thus, the lens barrel 4 in which the first lens 16 is incorporated is fixed by the fixing mechanism of the jig.
Then, as shown in FIGS. 1 and 7A, the second lens 18 is inserted inward of the lens barrel 14 from one opening of the lens barrel 4, and the outer peripheral surface of the second lens 18 is second mounted. Place on surface 1402. At this time, each lens moving claw 20 is retracted to the outside of the lens barrel 4.
Next, as shown in FIG. 3, only one lens moving claw 20A is moved from the lens moving notch 1406 toward the inside of the lens barrel 4, and the contact surface 2002 is brought into contact with the outer peripheral end surface of the second lens 18. The second lens 18 is moved toward each protrusion 1408.
As a result, as shown in FIG. 4, when the outer peripheral end surface of the second lens 18 comes into contact with each protrusion 1408, the second lens 18 is centered through the center of the second lens 18 as described above. Will pass on the central axis Z of the 2nd lens attachment part 14, and will be stopped in this state.
Then, as shown in FIGS. 5 and 7B, the other lens moving claw 20B is moved from the lens moving notch 1406 toward the inside of the lens barrel 4, and the contact surface 2002 of the second lens 18 is moved. Abut on the outer peripheral end face. Thereby, the second lens 18 is sandwiched between the contact surfaces 2002 of the two lens moving claws 20A and 20B.
In this state, as shown in FIG. 6, the second lens 18 is moved in a plane orthogonal to the central axis Z by the lens moving claws 20 A and 20 B, and the second lens 18 is moved with respect to the optical axis of the first lens 16. Align the optical axes to align.
Specifically, the second lens 18 and the first lens 18 are irradiated with a light beam indicating a centering chart image from one side (upper side in FIG. 1) in the central axis Z direction shown in FIG. The chart image formed by the lens 16 is detected by an image detector such as a CCD disposed on the other side (downward in FIG. 1) in the central axis Z direction shown in FIG. 1, and the detected chart image is displayed. To be displayed.
Then, the second lens 18 is moved in a plane orthogonal to the central axis Z by the lens moving claws 20A and 20B so that the chart image displayed on the display is correctly displayed. If the image on the chart is correctly displayed, the optical axis of the second lens 18 matches the optical axis of the first lens 16, and the alignment is completed. Such an alignment method is conventionally known.
[0012]
Then, in the state where the alignment is completed, an adhesive is filled in the gap between the outer peripheral end surface of the second lens 18 and the second placement surface 1402 and the standing wall 1404 so that the second lens 18 becomes the second lens. Adhere to the mounting portion 14. In the present embodiment, an ultraviolet curable adhesive is used as the adhesive, and the adhesive is cured by irradiating the filled adhesive with ultraviolet rays.
[0013]
According to the present embodiment, when the outer peripheral end surface of the second lens 18 is brought into contact with each protrusion 1408, the second lens 18 has a center line Y1 passing through the center of the second lens 18 so that the second lens 18 Since it passes through the central axis Z of the mounting portion 14, it is possible to prevent the second lens 18 from being greatly displaced with respect to the two lens moving claws 20A and 20B facing each other across the central axis Z. This is advantageous in stably and reliably holding the second lens 18 by 20A and 20B.
For example, as in the comparative example shown in FIG. 8, a configuration in which the two projecting portions 1408 are not provided in the second lens mounting portion 14 has the following drawbacks. That is, when the center of the second lens 18 is greatly deviated from the center axis Z of the second lens mounting portion 14, the second lens 18 must be moved greatly for alignment, but the lens moving claw 20 Interference with the lens moving notch 1408 makes alignment impossible.
In particular, when the lens device 2 is downsized or when a member such as the cam pin 6 has to be provided in the lens barrel 4 and the space for providing the lens moving notch 1408 is limited, as described above. Cause inconvenience.
On the other hand, the lens device 2 according to the present embodiment can eliminate such problems and is advantageous in reducing the size of the lens device 2.
Further, in the case of the comparative example described above, the lens moving claw 20 needs to have a relatively small outer dimension as compared with the lens moving notch 1408 in order to enable alignment of the second lens 18. For this reason, the strength of the lens moving claw 20 is lowered and bending occurs. For this reason, the amount of movement of the second lens 18 varies, making it difficult to perform highly accurate alignment. On the other hand, in the lens device 2 according to the present embodiment, it is not necessary to reduce the outer dimension of the lens moving claw 20, and the strength of the lens moving claw 20 can be ensured. It is advantageous for suppressing and performing highly accurate alignment.
Further, when the outer peripheral end surface of the second lens 18 is brought into contact with each protruding portion 1408, the center line Y1 passing through the center of the second lens 18 of the second lens 18 is the central axis of the second lens mounting portion 14. It will pass through Z. Thereby, since the optical axis position in the X direction of the second lens 18 is very close to the optical axis position of the first lens 16, the amount of movement to move the second lens 18 for alignment is small. Less time is required, which can greatly reduce the time required for alignment, which is advantageous for cost reduction.
Further, since the protruding portion 1408 has a very simple configuration of protrudingly provided on the second upright wall 1404 of the second lens mounting portion 14, the number of parts does not increase and the cost does not increase.
[0014]
In the present embodiment, the second lens 18 is the only lens to be aligned. However, a plurality of lens attachment portions are provided along the central axis of the lens barrel 4 so that the plurality of lenses can be aligned. May be.
The lens device of the present invention can be applied to an optical system of various imaging devices such as a film-type camera, a digital camera, or a video camera. Further, it can be applied to an optical system of an optical head (optical pickup) for an optical disk.
[0015]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a lens device and an assembling method that are advantageous in reducing the number of parts and reducing the size.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a configuration of a lens apparatus according to an embodiment.
FIG. 2 is a perspective view of a lens device.
FIG. 3 is an explanatory diagram of a centering operation in the lens device.
FIG. 4 is an explanatory diagram of a centering operation in the lens device.
FIG. 5 is an explanatory diagram of a centering operation in the lens device.
FIG. 6 is an explanatory diagram of a centering operation in the lens device.
FIG. 7 is an explanatory diagram showing a configuration of a lens device and a jig.
FIG. 8 is an explanatory diagram showing a configuration of a lens device as a comparative example.
[Explanation of symbols]
2 ... Lens device, 4 ... Lens barrel, 14 ... Second lens mounting portion, 18 ... Second lens, 1402 ... Second mounting surface, 1404 ... Second standing surface, 1406 ... Lens movement Notch part, 20A, 20B ... Lens moving claw.

Claims

A lens mounting portion, and a lens attached to the lens mounting portion,
The lens mounting portion includes an annular mounting surface on which the outer peripheral surface of the lens is mounted, and an annular standing wall that has an inner diameter larger than the outer diameter of the lens and rises from the outer periphery of the mounting surface. A lens device having two lens moving notches provided at opposite positions of the upright wall,
The two lens moving notches are configured such that the lens moving claw can move from the outside to the inside of the standing wall in the radial direction of the mounting surface through the lens moving notches,
Protrusions are respectively provided on the inner peripheral surface portions of the standing walls facing both sides of one of the two lens movement notches,
When the lens moving claw hits the outer peripheral end surface of the lens from the lens moving notch portion where the projecting portion is not provided, the lens is moved toward the other lens moving notch portion, whereby the lens in a state where the outer peripheral end face of the is in contact with the respective projecting portions, each said protrusion, said of imaginary line perpendicular to the imaginary line connecting the contact portion between the outer peripheral end face and the projecting portions of the lenses A center line passing through the center of the lens is formed so as to pass on the center axis of the lens mounting portion.
A lens device.

The lens device according to claim 1, wherein each of the protrusions is formed in a symmetrical shape with the lens moving notch interposed therebetween.

The lens device according to claim 1, wherein a plurality of the lens mounting portions are provided along the central axis.

An annular mounting surface on which the outer peripheral surface of the lens is mounted; an annular standing wall that stands up from the outer periphery of the mounting surface; and two lens movement notches provided at locations facing the upstanding wall; A lens mounting portion having a lens mounting method,
Protrusions projecting inward in the radial direction of the standing wall are provided on the inner peripheral surface portions of the standing wall on both sides facing the lens moving missing part of the two lens moving missing parts,
Place the lens outer peripheral surface on the mounting surface described above inside the upright wall,
Of the two lens moving notches, a lens moving claw is applied to the outer peripheral end surface of the lens from the lens moving notch where the protrusion is not provided, and the lens is directed toward the other lens moving notch. Move
By causing the outer peripheral end surface of the lens to abut on each protrusion, the lens passes through the center of the imaginary line orthogonal to the imaginary line connecting the outer peripheral end surface of the lens and the contact portion of each protrusion. Adjust the center line so that it passes on the center axis of the lens mounting part,
Thereafter, the lens moving claw is applied to the outer peripheral end surface of the lens from the lens moving notch portion on the side where the protruding portion is provided, whereby the outer peripheral end surface of the lens is sandwiched between the two lens moving claws, and the lens is moved to the lens. Move along the surface perpendicular to the central axis of the mounting part to perform alignment,
After the alignment, the lens is fixed to the lens mounting portion.
A method of assembling the lens device.

The lens apparatus assembling method according to claim 4, wherein the lens is fixed to the lens mounting portion by an adhesive.