JP4971632B2 - Zoom lens and imaging apparatus having the same - Google Patents
Zoom lens and imaging apparatus having the same Download PDFInfo
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- G02B15/00—Optical objectives with means for varying the magnification
- G02B15/14—Optical objectives with means for varying the magnification by axial movement of one or more lenses or groups of lenses relative to the image plane for continuously varying the equivalent focal length of the objective
- G02B15/144—Optical objectives with means for varying the magnification by axial movement of one or more lenses or groups of lenses relative to the image plane for continuously varying the equivalent focal length of the objective having four groups only
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- G02B15/144113—Optical objectives with means for varying the magnification by axial movement of one or more lenses or groups of lenses relative to the image plane for continuously varying the equivalent focal length of the objective having four groups only the first group being positive arranged +-++
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Description
本発明は、スチルカメラ、ビデオカメラ、銀塩写真用カメラそして電子スチルカメラなどに好適なズームレンズ及びそれを有する撮像装置に関するものである。 The present invention relates to a zoom lens suitable for a still camera, a video camera, a silver salt photography camera, an electronic still camera, and the like, and an imaging apparatus having the same.
最近、ビデオカメラ、デジタルスチルカメラ等の撮像装置では、画素数の多い(高画素の)固体撮像素子が多く使用されている。それに伴い、それらの撮像装置に用いる光学系には高性能のズームレンズが求められている。 Recently, imaging devices such as video cameras and digital still cameras have often used solid-state imaging devices having a large number of pixels (high pixels). Accordingly, high-performance zoom lenses are required for optical systems used in these image pickup apparatuses.
特に高画素の固体撮像素子用のズームレンズには単色の諸収差の補正のみならず、広い波長域での色収差の補正を十分に行うことが要望されている。 In particular, zoom lenses for high-pixel solid-state imaging devices are required not only to correct monochromatic aberrations but also to sufficiently correct chromatic aberrations in a wide wavelength range.
一般に高ズーム比のズームレンズでは望遠側のズーム位置の焦点距離が長いと、色収差については一次の色消しに加え、二次スペクトルの低減が重要になってくる。 In general, in a zoom lens with a high zoom ratio, if the focal length of the zoom position on the telephoto side is long, in addition to primary achromaticity, it is important to reduce the secondary spectrum for chromatic aberration.
10倍程度以上の高ズーム比を得るのに適したズームレンズとして、最も物体側のレンズ群を正の屈折力のレンズ群としたポジティブリード型のズームレンズがある。 As a zoom lens suitable for obtaining a high zoom ratio of about 10 times or more, there is a positive lead type zoom lens in which the most object side lens unit is a lens unit having a positive refractive power.
このうち、物体側より像側へ順に正、負、正、正の屈折力のレンズ群より成る4群構成のズームレンズがある。 Among these, there is a four-group zoom lens composed of lens groups having positive, negative, positive, and positive refractive power in order from the object side to the image side.
この4群ズームレンズにおいて第1レンズ群に異常分散材料(以上分散性を有する材料)より成るレンズを用いて色収差を補正したズームレンズが知られている(例えば特許文献1〜7)。 In this 4-group zoom lens, zoom lenses in which chromatic aberration is corrected using a lens made of an anomalous dispersion material (a material having dispersibility) in the first lens group are known (for example, Patent Documents 1 to 7).
特許文献1〜7のうち、例えば特許文献6では、ズーミングに際して、4つのレンズ群が移動する4群ズームタイプにおいて、第1レンズ群の最も像側の第3レンズに異常分散性のガラスより成るレンズを使用した実施例を開示している。 Among Patent Documents 1 to 7, for example, in Patent Document 6, in a four-group zoom type in which four lens groups move during zooming, the third lens closest to the image side of the first lens group is made of an anomalous dispersion glass. An embodiment using a lens is disclosed.
また物体側より像側へ順に、正、負、正、正、正の屈折力のレンズ群より成る5群構成のズームレンズがある。この5群ズームレンズにおいて異常分散材料より成るレンズを用いて色収差を補正したズームレンズが知られている(例えば特許文献9)。 In addition, there is a zoom lens having a five-group configuration including a lens group having positive, negative, positive, positive, and positive refractive powers in order from the object side to the image side. A zoom lens in which chromatic aberration is corrected using a lens made of an anomalous dispersion material in this 5-group zoom lens is known (for example, Patent Document 9).
特許文献8では、ズーミングに際して、第1レンズ群から第4レンズ群が移動し、フォーカスに際して第5レンズ群を移動させるズームタイプにおいて、第1レンズ群の最も像側の第3レンズに異常分散性のガラスより成るレンズを使用した実施例を開示している。 In Patent Document 8, in the zoom type in which the fourth lens group moves from the first lens group during zooming and the fifth lens group moves during focusing, the third lens closest to the image side of the first lens group has anomalous dispersion. An embodiment using a lens made of glass is disclosed.
また物体側より像側へ順に正、負、正、負、正の屈折力のレンズ群より成る5群構成のズームレンズがある。この5群ズームレンズにおいて異常分散材料より成るレンズを用いて色収差を補正したズームレンズが知られている(例えば特許文献9)。 In addition, there is a zoom lens having a five-group configuration including a lens group having positive, negative, positive, negative, and positive refractive power in order from the object side to the image side. A zoom lens in which chromatic aberration is corrected using a lens made of an anomalous dispersion material in this 5-group zoom lens is known (for example, Patent Document 9).
一方、ズームレンズにおいて一部のレンズ群を変位させて画像ブレを補正したものが知られている。
ポジティブリード型のズームレンズにおいて、望遠側のズーム位置における軸上色収差の二次スペクトルは、軸上光線の高さが高い正の屈折力の第1レンズ群にて多く発生しやすい。 In a positive lead type zoom lens, a secondary spectrum of axial chromatic aberration at the zoom position on the telephoto side is likely to occur in the first lens unit having a positive refractive power with a high axial ray height.
このため第1レンズ群の正レンズの材料に異常分散材料を用いて二次スペクトルを低減するのが効果的である。 For this reason, it is effective to reduce the secondary spectrum by using an anomalous dispersion material as the material of the positive lens of the first lens group.
一般に第1レンズ群で発生した色収差は第2レンズ群以降の各レンズ群の倍率が乗じられて結像性能に影響する。 In general, chromatic aberration generated in the first lens group is multiplied by the magnification of each lens group after the second lens group and affects the imaging performance.
このため、異常分散材料より成るレンズを第1レンズ群に使用することは、第1レンズ群以外のレンズ群に使用することに比べ、特に望遠側のズーム位置の軸上色収差を補正する上で効果が高い。 For this reason, using a lens made of an anomalous dispersion material for the first lens group is particularly effective for correcting axial chromatic aberration at the zoom position on the telephoto side, compared to using it for a lens group other than the first lens group. High effect.
しかしながら、一般に異常分散材料は膨張率が高く、かつ割れやすいため、通常のガラスに比べて加工が難しい。特に有効径の大きい第1レンズ群に用いる場合には加工が困難である。 However, in general, an anomalous dispersion material has a high expansion coefficient and is easily broken, so that it is difficult to process compared to ordinary glass. In particular, processing is difficult when used for the first lens group having a large effective diameter.
この他、異常分散材料と通常のガラスと組み合わせて接合レンズとして使用した場合、組み合わせるガラスとの膨張率が大きく異なる。このため、温度変化に対し面精度の劣化や接合強度の低下が生じる。 In addition, when used as a cemented lens in combination with an anomalous dispersion material and ordinary glass, the expansion coefficient differs greatly from the combined glass. For this reason, surface accuracy is deteriorated and bonding strength is reduced with respect to temperature changes.
そのため有効径の大きな第1レンズ群において、異常分散材料を接合レンズに用いずに、独立したレンズに使用する場合が多い。これによれば耐環境性能を向上させることができる。 Therefore, in the first lens group having a large effective diameter, the anomalous dispersion material is often used as an independent lens without being used as a cemented lens. According to this, environmental resistance performance can be improved.
特許文献1〜7の4群ズームレンズ、特許文献8,9の5群ズームレンズは、いずれも第1レンズ群に異常分散性のガラスより成るレンズを用いて色収差の補正を行っている。 The 4-group zoom lens of Patent Documents 1 to 7 and the 5-group zoom lens of Patent Documents 8 and 9 both correct chromatic aberration using a lens made of anomalous dispersion glass in the first lens group.
しかしながら、異常分散性のガラスより成るレンズの屈折力が第1レンズ群全体の正の屈折力に占める割合が適切でなく、ズーム領域が全般にわたり2次スペクトルの低減が必ずしも十分でない。 However, the ratio of the refractive power of the lens made of anomalous dispersion glass to the positive refractive power of the entire first lens group is not appropriate, and the reduction of the secondary spectrum is not necessarily sufficient over the entire zoom region.
異常分散材料より成るレンズを第1レンズ群に独立に用いるときには、第1レンズ群の全体のレンズ構成、特にズームタイプや第1レンズ群を構成する各レンズの材料や屈折力等を適切に設定するのが重要である。そうでないと、色収差、特に2次スペクトルを良好に補正し、高い光学性能を得るのが難しくなってくる。 When a lens made of an anomalous dispersion material is used independently for the first lens group, the entire lens configuration of the first lens group, particularly the zoom type and the material and refractive power of each lens constituting the first lens group are set appropriately. It is important to do. Otherwise, it becomes difficult to correct chromatic aberration, particularly the secondary spectrum, and obtain high optical performance.
本発明は、レンズ全長の短縮化と第1レンズ群の有効径の小型化を図り、耐環境性能の向上を達成しながら、広角端から望遠端に至る全ズーム範囲にわたり色収差を良好に補正し高い光学性能を有するズームレンズの提供を目的とする。 The present invention shortens the total lens length and reduces the effective diameter of the first lens group, and achieves improved environmental resistance while satisfactorily correcting chromatic aberration over the entire zoom range from the wide-angle end to the telephoto end. An object of the present invention is to provide a zoom lens having high optical performance.
本発明のズームレンズは、物体側より像側へ順に、正の屈折力の第1レンズ群と、負の屈折力の第2レンズ群と、正の屈折力の第3レンズ群と、正の屈折力の第4レンズ群より構成されるズームレンズであって、広角端に比べて望遠端において、前記第1レンズ群は物体側に位置し、前記第1レンズ群と前記第2レンズ群の間隔は大きくなり、前記第2レンズ群と前記第3レンズ群の間隔は小さくなり、ズーミングに際して前記第4レンズ群は物体側に凸形状の軌跡で移動し、フォーカシングに際して前記第4レンズ群が移動し、前記第1レンズ群は、物体側より像側へ順に、負レンズG11、正レンズG12、正レンズG13から構成され、前記正レンズG12の材料のアッベ数をνd2、前記正レンズG13の材料のアッベ数をνd3、前記負レンズG11と前記正レンズG12の合成焦点距離をf1a、前記正レンズG13の焦点距離をf1bとするとき、
70<νd3
0<νd3−νd2<30.0
2.0<f1a/f1b<20.0
なる条件を満足することを特徴としている。
The zoom lens according to the present invention includes, in order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a zoom lens composed of the fourth lens group refractive power, at the telephoto end than at the wide-angle end, the first lens group is located on the object side, the second lens group and the third lens group distance increases, the distance between the second lens group and the third lens group becomes small, the fourth lens group in zooming is moved along a locus convex to the object side, said fourth lens group upon focusing movement and, wherein the first lens group comprises, in order from the object side to the image side, a negative lens G11, a positive lens G12, and a positive lens G13, the material of the Abbe number of the positive lens G12 material vd2, the positive lens G13 Abbe number of νd3, before Serial f1a the combined focal length of the negative lens G11 and the positive lens G12, when said focal length of the positive lens G13 f1b,
70 <νd3
0 <νd3-νd2 <30.0
2.0 <f1a / f1b <20.0
It is characterized by satisfying the following conditions.
本発明によれば、全系が小型で広角端から望遠端に至る全ズーム範囲にわたり色収差を良好に補正した高い光学性能を有するズームレンズ及びそれを有する撮像装置が得られる。 According to the present invention, it is possible to obtain a zoom lens having high optical performance in which the entire system is small and the chromatic aberration is favorably corrected over the entire zoom range from the wide-angle end to the telephoto end, and an image pickup apparatus having the zoom lens.
以下、本発明のズームレンズ及びそれを有する撮像装置の実施例について説明する。 Embodiments of the zoom lens of the present invention and an image pickup apparatus having the same will be described below.
図1は実施例1のズームレンズの広角端(短焦点距離)におけるレンズ断面図である。図2,図3,図4はそれぞれ実施例1のズームレンズの広角端、中間のズーム位置、望遠端(長焦点距離)における収差図である。 FIG. 1 is a lens cross-sectional view at the wide-angle end (short focal length) of the zoom lens according to the first exemplary embodiment. 2, 3 and 4 are aberration diagrams of the zoom lens of Example 1 at the wide-angle end, the intermediate zoom position, and the telephoto end (long focal length), respectively.
図5は実施例2のズームレンズの広角端におけるレンズ断面図である。図6,図7,図8はそれぞれ実施例2のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。 FIG. 5 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the second exemplary embodiment. 6, 7, and 8 are aberration diagrams of the zoom lens of Example 2 at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively.
図9は実施例3のズームレンズの広角端におけるレンズ断面図である。図10,図11,図12はそれぞれ実施例3のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。 FIG. 9 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the third exemplary embodiment. 10, 11 and 12 are aberration diagrams of the zoom lens of Example 3 at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively.
図13は実施例4のズームレンズの広角端におけるレンズ断面図である。図14,図15,図16はそれぞれ実施例4のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。 FIG. 13 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the fourth exemplary embodiment. FIGS. 14, 15, and 16 are aberration diagrams of the zoom lens of Example 4 at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively.
図17は実施例5のズームレンズの広角端におけるレンズ断面図である。図18,図19,図20はそれぞれ実施例5のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。 FIG. 17 is a lens cross-sectional view at the wide-angle end of the zoom lens according to Embodiment 5. 18, 19 and 20 are aberration diagrams of the zoom lens of Example 5 at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively.
図21は実施例6のズームレンズの広角端におけるレンズ断面図である。図22,図23,図24はそれぞれ実施例6のズームレンズの広角端、中間のズーム位置、望遠端における収差図である。 FIG. 21 is a lens cross-sectional view at the wide-angle end of the zoom lens according to the sixth exemplary embodiment. FIGS. 22, 23, and 24 are aberration diagrams of the zoom lens according to the sixth embodiment at the wide-angle end, the intermediate zoom position, and the telephoto end, respectively.
図25は本発明のズームレンズを備えるカメラ(撮像装置)の要部概略図である。 FIG. 25 is a schematic diagram of a main part of a camera (image pickup apparatus) including the zoom lens according to the present invention.
各実施例のズームレンズはビデオカメラやデジタルカメラそして銀塩フィルムカメラ等の撮像装置に用いられる撮影レンズ系である。 The zoom lens of each embodiment is a photographic lens system used in an imaging apparatus such as a video camera, a digital camera, or a silver salt film camera.
レンズ断面図において、左方が被写体側(前方)で、右方が像側(後方)である。L1は正の屈折力(光学的パワー=焦点距離の逆数)の第1レンズ群、L2は負の屈折力の第2レンズ群、L3は正の屈折力の第3レンズ群、L4は正の屈折力の第4レンズ群である。 In the lens cross-sectional view, the left side is the subject side (front), and the right side is the image side (rear). L1 is a first lens group having a positive refractive power (optical power = reciprocal of focal length), L2 is a second lens group having a negative refractive power, L3 is a third lens group having a positive refractive power, and L4 is positive. It is the 4th lens group of refractive power.
SPは開口絞りであり、第3レンズ群L3の物体側に配置している。FPはフレアー絞りであり、第3レンズ群L3の像側に配置しており、不要光と遮光している。 SP is an aperture stop, which is disposed on the object side of the third lens unit L3. FP is a flare stop, which is disposed on the image side of the third lens unit L3 and shields unnecessary light.
Gは光学フィルター、フェースプレート、水晶ローパスフィルター、赤外カットフィルター等に相当する光学ブロックである。 G is an optical block corresponding to an optical filter, a face plate, a quartz low-pass filter, an infrared cut filter, or the like.
IPは像面である。像面IPは、各実施例のズームレンズをビデオカメラやデジタルスチルカメラの撮影光学系として使用する際には、CCDセンサやCMOSセンサ等の固体撮像素子(光電変換素子)の撮像面に相当する。銀塩フィルム用カメラの撮影光学系として使用する際には、フィルム面に相当する。 IP is the image plane. The image plane IP corresponds to an imaging plane of a solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor when the zoom lens of each embodiment is used as a photographing optical system of a video camera or a digital still camera. . When used as a photographing optical system for a silver salt film camera, it corresponds to a film surface.
収差図において、d,gは各々d線及びg線、ΔM,ΔSはメリディオナル像面、サジタル像面である。倍率色収差はg線によって表している。ωは半画角、FnoはFナンバーである。 In the aberration diagrams, d and g are d-line and g-line, respectively, and ΔM and ΔS are a meridional image plane and a sagittal image plane. Lateral chromatic aberration is represented by the g-line. ω is a half angle of view, and Fno is an F number.
尚、以下の各実施例において広角端と望遠端は変倍用レンズ群が機構上光軸上を移動可能な範囲の両端に位置したときのズーム位置をいう。 In the following embodiments, the wide-angle end and the telephoto end refer to zoom positions when the zoom lens unit is positioned at both ends of a range in which the mechanism can move on the optical axis.
各実施例では、広角端から望遠端へのズーミングに際して、矢印のように、各レンズ群及び開口絞りSPを移動させている。 In each embodiment, when zooming from the wide-angle end to the telephoto end, the lens units and the aperture stop SP are moved as indicated by arrows.
具体的には、広角端から望遠端へのズーミングに際して、第1レンズ群L1を物体側へ、第2レンズ群L2を像側へ移動させている。第3レンズ群L3を物体側へ凸形状の軌跡で移動させている。第4レンズ群L4を物体側に凸形状の軌跡又はその一部の軌跡に沿って移動させている。 Specifically, during zooming from the wide-angle end to the telephoto end, the first lens unit L1 is moved to the object side, and the second lens unit L2 is moved to the image side. The third lens unit L3 is moved to the object side along a convex locus. The fourth lens unit L4 is moved along a convex locus on the object side or a partial locus thereof.
各実施例では、広角端に比べ望遠端で、第1レンズ群L1と第2レンズ群L2の間隔が大きくなり、第2レンズ群L2と第3レンズ群L3の間隔が小さくなるように、各レンズ群を移動させている。 In each embodiment, the distance between the first lens unit L1 and the second lens unit L2 is larger at the telephoto end than the wide angle end, and the interval between the second lens unit L2 and the third lens unit L3 is smaller. The lens group is moved.
また第4レンズ群L4を前述の如く移動させて、変倍に伴う像面変動を補正している。 Further, the fourth lens unit L4 is moved as described above to correct the image plane variation accompanying the zooming.
各実施例において、第1レンズ群L1をズーミングに際して移動させることにより、広角端でのレンズ全長を短縮し光軸方向におけるレンズ系全体の小型化を図っている。また広角端にて、第1レンズ群L1と開口絞りSPの間隔を短縮して第1レンズ群L1の有効径を小さくしている。 In each embodiment, by moving the first lens unit L1 during zooming, the total lens length at the wide-angle end is shortened and the entire lens system in the optical axis direction is downsized. At the wide angle end, the distance between the first lens unit L1 and the aperture stop SP is shortened to reduce the effective diameter of the first lens unit L1.
また第3レンズ群L3の像側に第3レンズ群L3とズーミングに際して一体的に移動するフレアーカット絞りFPを設けている。フレアーカット絞りFPは、第3レンズ群L3で防振に際して移動させるときは不動(固定)である。このフレアーカット絞りFPを設けることによって中間のズーム位置において不要光をカットしている。 Further, a flare cut stop FP that moves integrally with the third lens unit L3 during zooming is provided on the image side of the third lens unit L3. The flare cut stop FP does not move (fixed) when moved by the third lens unit L3 during image stabilization. By providing this flare cut stop FP, unnecessary light is cut at an intermediate zoom position.
実施例1乃至5において、開口絞りSPは、望遠端に比べ広角端で像側に位置するように、第3レンズ群L3と異なる軌跡で独立に移動している。これにより、第1レンズ群L1の有効径を小さくし、望遠側のズーム位置において画面周辺での光量の急激な低下を緩和している。 In Examples 1 to 5, the aperture stop SP is independently moved along a locus different from that of the third lens unit L3 so as to be positioned on the image side at the wide-angle end compared to the telephoto end. As a result, the effective diameter of the first lens unit L1 is reduced, and the sudden decrease in the amount of light around the screen is reduced at the zoom position on the telephoto side.
実施例6において、開口絞りSPは、ズーミングに際して第3レンズ群L3と一体に移動している。これにより独立に移動するレンズ群の数を減らして鏡筒構造の簡素化を図っている。 In Example 6, the aperture stop SP moves together with the third lens unit L3 during zooming. This reduces the number of lens groups that move independently, thereby simplifying the lens barrel structure.
開口絞りSPを固定とする場合は、絞りユニットを移動させる必要がないためズーミングの際、駆動させるアクチュエータの駆動トルクを小さく設定でき省電力化の点で有利である。 When the aperture stop SP is fixed, it is not necessary to move the aperture unit, so that the driving torque of the actuator to be driven can be set small during zooming, which is advantageous in terms of power saving.
ズーミングに際して、第4レンズ群L4を前述の如く移動させることにより、第3レンズ群L3と第4レンズ群L4との空間の有効利用を図り、レンズ全長の短縮化を図っている。 During zooming, the fourth lens unit L4 is moved as described above, so that the space between the third lens unit L3 and the fourth lens unit L4 is effectively used, and the total lens length is shortened.
また第4レンズ群L4を光軸上移動させてフォーカシングを行うリアフォーカス式を採用している。 Further, a rear focus type is employed in which the fourth lens unit L4 is moved on the optical axis to perform focusing.
第4レンズ群L4に関する実線の曲線4aと点線の曲線4bは、各々無限遠物体と近距離物体にフォーカスしているときの広角端から望遠端へのズーミングに伴う像面変動を補正するための移動軌跡を示している。 A solid curve 4a and a dotted curve 4b relating to the fourth lens unit L4 are used to correct image plane variation caused by zooming from the wide-angle end to the telephoto end when focusing on an object at infinity and a short-distance object, respectively. The movement trajectory is shown.
各実施例において、例えば、望遠端において無限遠物体から近距離物体へのフォーカスは、矢印4cに示すように、第4レンズ群L4を前方に繰り出すことで行う。 In each embodiment, for example, focusing from an infinitely distant object to a close object at the telephoto end is performed by extending the fourth lens unit L4 forward as indicated by an arrow 4c.
尚、各実施例では4つのレンズ群で構成されるズームレンズを示しているが、第1レンズ群L1の物体側又は、第4レンズ群L4の像側に必要に応じて屈折力のあるレンズ群やコンバーターレンズ群等を設けても良い。 In each embodiment, a zoom lens composed of four lens groups is shown. However, a lens having refractive power as required on the object side of the first lens group L1 or the image side of the fourth lens group L4. A group or a converter lens group may be provided.
次に各実施例のレンズ構成の特徴について説明する。 Next, the features of the lens configuration of each example will be described.
以下、各レンズ群のレンズ構成は、物体側から像側へ順で示す。 Hereinafter, the lens configuration of each lens group is shown in order from the object side to the image side.
第1レンズ群L1は、物体側が凸面でメニスカス形状の負レンズG11と両凸形状の正レンズG12とを接合した全体として正の屈折力の接合レンズと、物体側が凸面でメニスカス形状の正レンズG13とで構成されている。 The first lens unit L1 includes a cemented lens having a positive refractive power as a whole and a meniscus negative lens G11 having a convex surface on the object side and a biconvex positive lens G12, and a meniscus positive lens G13 having a convex surface on the object side. It consists of and.
このようなレンズ構成にて、望遠側のズーム位置において二次スペクトルを良好に補正するには、第1レンズ群L1の正レンズに異常分散材料を用いるのが効果的である。 In order to satisfactorily correct the secondary spectrum at the telephoto zoom position with such a lens configuration, it is effective to use an anomalous dispersion material for the positive lens of the first lens unit L1.
しかしながら、異常分散性を有する硝材は通常の異常分散性を有しない硝材に比べて加工が難しい。 However, a glass material having anomalous dispersion is difficult to process compared to a glass material having no anomalous dispersion.
第1レンズ群L1の正レンズG12と正レンズG13の2枚の正レンズの材料に異常分散材料を使用すると、1枚の正レンズに使用する場合と比較して色収差の補正は有利である。 When an anomalous dispersion material is used as the material for the two positive lenses G12 and G13 of the first lens unit L1, it is advantageous to correct chromatic aberration as compared with the case of using one positive lens.
しかしながら、第1レンズ群L1のレンズの有効径は他のレンズ群のレンズと比較して有効径が大きい。このため、レンズの製造が難しくなる。またズーム比が10倍程度のズームレンズでは、第1レンズ群L1を異常分散材料より成る1つの正レンズより構成することで、望遠端における軸上色収差の補正が容易となる。 However, the effective diameter of the lens of the first lens group L1 is larger than that of the lenses of the other lens groups. For this reason, manufacture of a lens becomes difficult. In a zoom lens having a zoom ratio of about 10 times, the first lens unit L1 is composed of one positive lens made of an anomalous dispersion material, so that it is easy to correct axial chromatic aberration at the telephoto end.
その際、異常分散材料より成る正レンズを、正レンズG12にせず正レンズG13とするのが良い。 At this time, the positive lens made of an anomalous dispersion material is preferably the positive lens G13 instead of the positive lens G12.
一般に、第1レンズ群L1の有効径は像面の最も高い位置(画面周辺部)に結像する最外軸外光線で決まっている。前述のレンズ構成より成る第1レンズ群L1において、一般に像面に近いレンズほど最外軸外光線の高さが低くなり、有効径は小さい。 In general, the effective diameter of the first lens unit L1 is determined by the outermost off-axis light beam that forms an image at the highest position on the image plane (periphery of the screen). In the first lens unit L1 having the lens configuration described above, the height of the outermost off-axis light beam is generally lower and the effective diameter is smaller as the lens is closer to the image plane.
そのため異常分散材料を使用する正レンズとしては、有効径がより小さな正レンズG13を選択した方が、正レンズG12を選択する場合に比べて製造が容易になる。 For this reason, as a positive lens using an anomalous dispersion material, it is easier to manufacture a positive lens G13 having a smaller effective diameter than a positive lens G12.
負レンズG11と正レンズG12は貼り合せて接合レンズとしても良いし、2つのレンズの間に間隔を設けて2つの単独のレンズとしても良い。 The negative lens G11 and the positive lens G12 may be bonded together to form a cemented lens, or two single lenses may be provided by providing an interval between the two lenses.
各実施例では負レンズG11と正レンズG12を貼り合せて接合レンズとしている。 In each embodiment, the negative lens G11 and the positive lens G12 are bonded to form a cemented lens.
接合レンズにすれば負レンズG11の像側の面または正レンズG12の物体側の面もしくはその両面での面反射により光線が結像面に達し、ゴーストが発生するのを低減できる。 If a cemented lens is used, it is possible to reduce the occurrence of a ghost due to light rays reaching the imaging plane due to surface reflection on the image side surface of the negative lens G11 or the object side surface of the positive lens G12 or on both surfaces thereof.
また負レンズG11と正レンズG12を接合レンズにすれば、負レンズG11と正レンズG12との相対偏心による光学結像性能への敏感度を低くすることができ、製造が容易となる。 If the negative lens G11 and the positive lens G12 are cemented lenses, the sensitivity to the optical imaging performance due to the relative decentering of the negative lens G11 and the positive lens G12 can be reduced, and the manufacturing becomes easy.
一方、負レンズG11と正レンズG12の間に空気間隔を設けて2つの単独のレンズとすれば、負レンズG11の像側の面と正レンズG12の物体側の面とで異なる曲率半径とすることができ、収差補正の自由度が増す。 On the other hand, if an air gap is provided between the negative lens G11 and the positive lens G12 to form two single lenses, the curvature radius differs between the image side surface of the negative lens G11 and the object side surface of the positive lens G12. This increases the degree of freedom of aberration correction.
異常分散性材料は、異常分散性を有しない通常のガラスに比べて、一般に線膨張係数が大きい。 Anomalous dispersive materials generally have a larger linear expansion coefficient than ordinary glass that does not have anomalous dispersibility.
そのため負レンズG11と正レンズG12を貼り合わせた接合レンズにおいて、正レンズG12に異常分散材料を使用すると、温度変化で接合面に膨張係数の差による歪みが生じる。これは、大口径になるに従いレンズ面の変形による光学性能が劣化し、又接合強度が低下する。 For this reason, in the cemented lens in which the negative lens G11 and the positive lens G12 are bonded together, when an anomalous dispersion material is used for the positive lens G12, distortion due to a difference in expansion coefficient occurs on the cemented surface due to temperature change. This is because the optical performance deteriorates due to the deformation of the lens surface and the bonding strength decreases as the diameter increases.
これはレンズの径が大きくなるほど顕著になる。そのため有効径が大きな第1レンズ群L1において、負レンズG11と正レンズG12を接合レンズとした場合は、正レンズG13に線膨張係数の大きな異常分散材料を使用した方が、耐温度環境性能が向上する。 This becomes more prominent as the lens diameter increases. Therefore, in the first lens unit L1 having a large effective diameter, when the negative lens G11 and the positive lens G12 are cemented lenses, the use of an anomalous dispersion material having a large linear expansion coefficient for the positive lens G13 has better temperature resistance and environmental performance. improves.
以上の理由により、各実施例のズームレンズでは、第1レンズ群L1の正レンズG13に異常分散材料から成るレンズを用いている。これにより望遠側のズーム位置における軸上色収差の二次スペクトルの補正を行っている。 For the above reasons, in the zoom lens of each embodiment, a lens made of an anomalous dispersion material is used as the positive lens G13 of the first lens unit L1. This corrects the secondary spectrum of axial chromatic aberration at the zoom position on the telephoto side.
正レンズG12の材料のd線に対するアッベ数をνd2、正レンズG13の材料のd線に対するアッベ数をνd3とする。負レンズG11と正レンズG12の合成焦点距離をf1a、正レンズG13の焦点距離をf1bとする。 The Abbe number of the material of the positive lens G12 with respect to the d-line is νd2, and the Abbe number of the material of the positive lens G13 with respect to the d-line is νd3. The combined focal length of the negative lens G11 and the positive lens G12 is f1a, and the focal length of the positive lens G13 is f1b.
このとき、
70<νd3 ‥‥‥(1)
0<νd3−νd2<30.0 ‥‥‥(2)
2.0<f1a/f1b<20.0‥‥‥(3)
なる条件式を満足している。
At this time,
70 <νd3 (1)
0 <νd3-νd2 <30.0 (2)
2.0 <f1a / f1b <20.0 (3)
The following conditional expression is satisfied.
条件式(1)乃至(3)は望遠側のズーム位置において軸上色収差の二次スペクトルの補正を良好に行うための条件式である。フラウンホーファー線のd線、F線、C線、g線における材料の屈折率をNd、NF、NC、Ngとするとき、材料のアッベ数νd、部分分散比をθgFは、
νd=(Nd−1)/(NF−NC)
θgF=(Ng−NF)/(NF−NC)
で表される。
Conditional expressions (1) to (3) are conditional expressions for satisfactorily correcting the secondary spectrum of axial chromatic aberration at the zoom position on the telephoto side. When the refractive index of the material in the d-line, F-line, C-line, and g-line of the Fraunhofer line is Nd, NF, NC, Ng, the Abbe number νd of the material and the partial dispersion ratio θgF are
νd = (Nd−1) / (NF−NC)
θgF = (Ng−NF) / (NF−NC)
It is represented by
望遠側のズーム位置において、軸上色収差の補正が一次でなされている状態(一次の色消し)では通常、g線等の短波長側にて色収差の補正が過剰となる。基準波長(例えばd線)のピント位置に対して短波長のピント位置はオーバー(補正過剰)傾向となる。 In a state where the axial chromatic aberration is corrected primarily at the zoom position on the telephoto side (primary achromatic), correction of chromatic aberration is usually excessive on the short wavelength side such as the g-line. The focus position of the short wavelength tends to be over (overcorrected) with respect to the focus position of the reference wavelength (for example, d line).
一般にある光学媒質においては短波長ほど屈折率が高くなる傾向がある。このため、短波長側における屈折率が高くなる度合いが強い材料を正レンズに用いれば、基準波長に対する短波長のピントのオーバー傾向が低減される。 In general, in an optical medium, the refractive index tends to increase as the wavelength becomes shorter. For this reason, if a material having a high degree of refractive index on the short wavelength side is used for the positive lens, the tendency of focusing on the short wavelength with respect to the reference wavelength is reduced.
よって部分分散比θgFが大きい材料を正レンズに用いるとg線のピントのオーバー傾向が低減されることになる。 Therefore, when a material having a large partial dispersion ratio θgF is used for the positive lens, the tendency of the g-line to be overfocused is reduced.
一般に光学材料ではアッベ数νdと部分分散比θgFには相関があることが知られている。例えば縦軸に部分分散比θgFの値を取り、横軸にアッベ数νdを取ったグラフを用いる。 In general, it is known that there is a correlation between the Abbe number νd and the partial dispersion ratio θgF in an optical material. For example, a graph is used in which the value of the partial dispersion ratio θgF is taken on the vertical axis and the Abbe number νd is taken on the horizontal axis.
このとき、オハラ社製の商品名PBM2(νd=36.26、θgF=0.5828)の点とオハラ社製の商品名NSL7(νd=60.49、θgF=0.5436)の点を結んだ線を基準線とする。このとき多くの光学ガラスの分布としてはアッベ数νdが35程度より小さい高分散材料は基準線より上側に存在している。 At this time, the point of the product name PBM2 (νd = 36.26, θgF = 0.5828) manufactured by OHARA and the point of the product name NSL7 (νd = 60.49, θgF = 0.5436) manufactured by OHARA are connected. The ellipse line is the reference line. At this time, as a distribution of many optical glasses, a high dispersion material having an Abbe number νd smaller than about 35 exists above the reference line.
又、アッベ数νdが35から65程度までの低分散材料は基準線より下側に位置するものが多い。又、アッベ数νdが60以上にて基準線より上側に位置する異常分散材料が存在している。 Further, many low dispersion materials having an Abbe number νd of about 35 to 65 are located below the reference line. Further, there is an anomalous dispersion material located above the reference line when the Abbe number νd is 60 or more.
第1レンズ群L1の正レンズに使用する低分散材料に関しては基準線より上側に位置するものを使用するのが二次スペクトルの補正に対し効果的である。基準線から離れるほど補正効果が高まるが、特にアッベ数νdが71を超える材料では基準線から大きく上側に離れた範囲に位置する。 For the low-dispersion material used for the positive lens of the first lens unit L1, it is effective for correcting the secondary spectrum to use a material that is located above the reference line. The correction effect increases as the distance from the reference line increases. In particular, the material whose Abbe number νd exceeds 71 is positioned in a range far away from the reference line.
条件式(1)の下限を超えて第1レンズ群L1の正レンズG13の材料にアッベ数νdが71を下回る材料を使用すると、十分な異常分散性を得ることができなくなる。特に、望遠側のズーム位置での軸上色収差の二次スペクトルの補正が十分に行えない。 If a material whose Abbe number νd is less than 71 is used as the material of the positive lens G13 of the first lens unit L1 exceeding the lower limit of the conditional expression (1), sufficient anomalous dispersion cannot be obtained. In particular, the correction of the secondary spectrum of axial chromatic aberration at the zoom position on the telephoto side cannot be performed sufficiently.
また主分散(NF−NC)が大きくなるため、正レンズG13にあまり大きな屈折力を与えることができない。その結果、第1レンズ群L1の屈折力を十分な値に保てなくなり、レンズ全長の短縮化と第1レンズ群L1の有効径の小型化が困難となる。 Further, since the main dispersion (NF-NC) becomes large, it is not possible to give a large refractive power to the positive lens G13. As a result, the refractive power of the first lens unit L1 cannot be maintained at a sufficient value, and it becomes difficult to shorten the total lens length and to reduce the effective diameter of the first lens unit L1.
条件式(1)の数値は、更に好ましくは、次の如く設定するのが良い。 The numerical value of conditional expression (1) is more preferably set as follows.
71<νd3 ‥‥‥(1a)
条件式(2)の上限を超えると第1レンズ群L1の正レンズG12のアッベ数νd2が小さくなり、主分散(NF−NC)の値が大きくなり負レンズG11とでの一次の色消しが困難となる。
71 <νd3 (1a)
When the upper limit of conditional expression (2) is exceeded, the Abbe number νd2 of the positive lens G12 in the first lens unit L1 decreases, the value of main dispersion (NF-NC) increases, and primary achromaticity with the negative lens G11 is lost. It becomes difficult.
そのため第1レンズ群L1で生じる軸上色収差が大きくなり、特に望遠側のズーム位置で光学性能が低下してくる。また条件式(2)の下限を超えると正レンズG12のアッベ数νd2が正レンズG13のアッベ数νd3よりも大きな値を持ち正レンズG12の材料も異常分散性を有することになる。 Therefore, the longitudinal chromatic aberration generated in the first lens unit L1 increases, and the optical performance deteriorates particularly at the zoom position on the telephoto side. If the lower limit of conditional expression (2) is exceeded, the Abbe number νd2 of the positive lens G12 is larger than the Abbe number νd3 of the positive lens G13, and the material of the positive lens G12 also has anomalous dispersion.
この結果、第1レンズ群L1の正レンズG13のみに異常分散材料を用いることが難しくなってくる。 As a result, it becomes difficult to use an anomalous dispersion material only for the positive lens G13 of the first lens unit L1.
条件式(2)の数値範囲は望ましくは次の如く設定すると良い。 The numerical range of conditional expression (2) is preferably set as follows.
0<νd3−νd2<26.0 ‥‥‥(2a)
第1レンズ群L1の異常分散材料より成る正レンズG13による二次スペクトルの補正の効果を高めるには正レンズG13の屈折力をある程度強める必要がある。
0 <νd3-νd2 <26.0 (2a)
In order to enhance the effect of correcting the secondary spectrum by the positive lens G13 made of the anomalous dispersion material of the first lens unit L1, it is necessary to increase the refractive power of the positive lens G13 to some extent.
条件式(3)は正レンズG13への屈折力の配分を規定するものである。 Conditional expression (3) defines the distribution of refractive power to the positive lens G13.
条件式(3)の上限を超えると、正レンズG13の焦点距離f1bが小さくなりすぎて正レンズG13の曲率がきつくなり、望遠側のズーム位置において球面収差の補正が困難となる。 If the upper limit of conditional expression (3) is exceeded, the focal length f1b of the positive lens G13 becomes too small and the curvature of the positive lens G13 becomes too tight, making it difficult to correct spherical aberration at the zoom position on the telephoto side.
条件式(3)の下限を超えると、正レンズG13の屈折力が弱くなりすぎて、異常分散材料を使用したことによる望遠側のズーム位置における二次スペクトルの補正効果が小さくなり軸上色収差の補正が不十分となる。 If the lower limit of conditional expression (3) is exceeded, the refractive power of the positive lens G13 becomes too weak, and the effect of correcting the secondary spectrum at the zoom position on the telephoto side due to the use of the anomalous dispersion material becomes small, and axial chromatic aberration is reduced. Correction is insufficient.
第1レンズ群L1の正レンズG13の異常分散材料は、例えば実施例1乃至3においては株式会社オハラ社製の商品名S−FPL51(屈折率1.49700、アッベ数81.5)である。 The anomalous dispersion material of the positive lens G13 of the first lens unit L1 is, for example, the product name S-FPL51 (refractive index: 1.49700, Abbe number: 81.5) manufactured by OHARA INC. In Examples 1 to 3.
実施例4においては株式会社オハラ社製の商品名S−FPL53(屈折率1.48750、アッベ数95.0)である。 In Example 4, trade name S-FPL53 (refractive index: 1.48750, Abbe number: 95.0) manufactured by OHARA INC.
実施例5,6においては株式会社住田光学ガラス社製の商品名K−GFK70(屈折率1.56907、アッベ数71.3)である。 In Examples 5 and 6, trade name K-GFK70 (refractive index 1.56907, Abbe number 71.3) manufactured by Sumita Optical Glass Co., Ltd. is used.
なお条件式(3)は望遠側のズーム位置において、軸上色収差の二次スペクトルの補正効果をより高めるためには次の如くに設定すると良い。 Conditional expression (3) is preferably set as follows in order to further enhance the correction effect of the secondary spectrum of axial chromatic aberration at the zoom position on the telephoto side.
2.3<f1a/f1b<16.0 ‥‥‥(3a)
また更に望ましくは次の如くに設定するのが良い。
2.3 <f1a / f1b <16.0 (3a)
More preferably, it is preferable to set as follows.
2.5<f1a/f1b<14.0 ‥‥‥(3b)
これによれば第1レンズ群L1における正レンズG13の材料の異常分散性を望遠側のズーム位置において軸上色収差の二次スペクトルの補正に対してより効果的に作用させることができる。
2.5 <f1a / f1b <14.0 (3b)
According to this, the anomalous dispersion of the material of the positive lens G13 in the first lens unit L1 can be more effectively applied to the correction of the secondary spectrum of axial chromatic aberration at the zoom position on the telephoto side.
第1レンズ群L1の正レンズG13の材料の部分分散比をθgFとするとき、
0.52<θgF ‥‥‥(4)
の条件式を満足している。
When the partial dispersion ratio of the material of the positive lens G13 of the first lens unit L1 is θgF,
0.52 <θgF (4)
Is satisfied.
条件式(4)は第1レンズ群L1の正レンズG13に使用する材料の異常分散性を規定したものである。 Conditional expression (4) defines the anomalous dispersion of the material used for the positive lens G13 of the first lens unit L1.
条件式(4)の下限を超えて第1レンズ群L1の正レンズG13の材料の部分分散比θgFが小さくなると、十分な異常分散性を得ることができなくなる。この結果、望遠側のズーム位置において軸上色収差の二次スペクトルの補正が不十分となる。 If the partial dispersion ratio θgF of the material of the positive lens G13 of the first lens unit L1 is reduced beyond the lower limit of the conditional expression (4), sufficient anomalous dispersion cannot be obtained. As a result, correction of the secondary spectrum of axial chromatic aberration is insufficient at the zoom position on the telephoto side.
条件式(4)の数値は、更に好ましくは次の如く設定するのが良い。 The numerical value of conditional expression (4) is more preferably set as follows.
0.53<θgF ‥‥‥(4a)
第1レンズ群L1の正レンズG13の物体側の面の曲率半径をR31、像側の面の曲率半径をR32とするとき、
1.0<(R31+R32)/(R32−R31)<2.0 ‥‥‥(5)
の条件式を満足している。
0.53 <θgF (4a)
When the radius of curvature of the object side surface of the positive lens G13 of the first lens unit L1 is R31 and the radius of curvature of the image side surface is R32,
1.0 <(R31 + R32) / ( R32 − R31 ) <2.0 (5)
Is satisfied.
条件式(5)は正レンズG13のレンズ形状を規定するものである。 Conditional expression (5) defines the lens shape of the positive lens G13.
条件式(5)の上限を超えて正レンズG13のメニスカス形状の度合いが強くなりすぎると、物体側の面の曲率半径R31が小さくなる。この結果、望遠側のズーム位置において周辺光束が正レンズG13に入射する入射角度が大きくなりすぎ、球面収差と非点収差が大きく発生してくる。 When the upper limit of conditional expression (5) is exceeded and the meniscus shape of the positive lens G13 becomes too strong, the radius of curvature R31 of the object side surface becomes small. As a result, the incident angle at which the peripheral light beam enters the positive lens G13 becomes too large at the zoom position on the telephoto side, resulting in large spherical aberration and astigmatism.
一方、条件式(5)の下限を超えて正レンズG13の両面が凸形状となると、正レンズG13の像側の面でズーム全域にわたり周辺光束の入射角度が大きくなりすぎる。この結果、非点収差が大きく発生し、他の面で補正しきれなくなる。条件式(5)は更に好ましくは、次の如くに設定するのが良い。 On the other hand, if both surfaces of the positive lens G13 are convex beyond the lower limit of the conditional expression (5), the incident angle of the peripheral luminous flux becomes too large over the entire zoom range on the image side surface of the positive lens G13. As a result, a large amount of astigmatism occurs and cannot be corrected on other surfaces. Conditional expression (5) is more preferably set as follows.
1.1<(R31+R32)/(R32−R31)<1.8 ‥‥‥(5a)
条件式(5)は、更に望ましくは次の如くに設定すると、特に望遠側のズーム位置において球面収差と非点収差の補正が良好に行えるので良い。
1.1 <(R31 + R32) / ( R32 − R31 ) <1.8 (5a)
If conditional expression (5) is more desirably set as follows, spherical aberration and astigmatism can be favorably corrected particularly at the zoom position on the telephoto side.
1.15<(R31+R32)/(R32−R31)<1.6 ‥‥‥(5b)
デジタルスチルカメラ用のズームレンズでは高解像力が要求されており、特にズーミングに伴う倍率色収差の変動を良好に補正することが重要となっている。
1.15 <(R31 + R32) / ( R32 − R31 ) <1.6 (5b)
A zoom lens for a digital still camera is required to have a high resolving power. In particular, it is important to satisfactorily correct a change in lateral chromatic aberration due to zooming.
そのため各実施例のズームレンズでは、主たる変倍作用を有する第2レンズ群L2を次の如く構成している。物体側に比べ像側に屈折力の絶対値が大きく、像側の面が凹でメニスカス形状の負レンズ、負レンズ、物体側の面が凸形状の正レンズの3枚のレンズで構成している。これによって第2レンズ群L2の主点の色消しを効果的に行ってズーミングに伴う倍率色収差の変動を良好に補正している。 Therefore, in the zoom lens of each embodiment, the second lens unit L2 having a main zooming action is configured as follows. The absolute value of the refractive power is larger on the image side than on the object side, and it is composed of three lenses: a negative lens with a negative surface on the image side, a negative lens, and a positive lens with a convex surface on the object side. Yes. As a result, the principal point of the second lens unit L2 is effectively achromatic, and the variation in lateral chromatic aberration due to zooming is corrected well.
10倍程度の高ズーム比を有するズームレンズを有するスチルカメラやビデオカメラ等の撮像装置では、手振れ等の振動による撮影画像のぶれを補正する防振機能を有することが強く要望される。 In an imaging apparatus such as a still camera or a video camera having a zoom lens having a high zoom ratio of about 10 times, it is strongly desired to have an image stabilization function for correcting shake of a captured image due to vibration such as camera shake.
各実施例では、第3レンズ群L3の全部を光軸の垂直方向の成分を持つように移動(変位)させることにより、光学系全体が振動したときの撮影画像のぶれを補正している。 In each embodiment, the entire third lens unit L3 is moved (displaced) so as to have a component in the direction perpendicular to the optical axis, thereby correcting blurring of the captured image when the entire optical system vibrates.
なお、第3レンズ群L3の一部を光軸と垂直方向の成分を持つように移動させて撮影画像のぶれを補正しても良い。 Note that a blur of the captured image may be corrected by moving a part of the third lens unit L3 so as to have a component in a direction perpendicular to the optical axis.
光学性能、特に防振時の光学性能を良好に維持しつつ光学全長の小型化を達成するために、第3レンズ群L3を2枚の正レンズと1枚の負レンズより構成している。 The third lens unit L3 includes two positive lenses and one negative lens in order to achieve a reduction in the overall optical length while maintaining good optical performance, particularly optical performance during image stabilization.
特に第3レンズ群L3を、物体側の面が凸形状の正レンズと、物体側に比べ像側に屈折力の絶対値が大きく、像側が凹面でメニスカス形状の負レンズを有するようにしている。これによって収差補正を良好に行い、かつレンズ全長を短縮している。 In particular, the third lens unit L3 includes a positive lens having a convex surface on the object side and a negative meniscus lens having a large refractive power on the image side and a concave surface on the image side compared to the object side. . As a result, aberration correction is performed satisfactorily and the total lens length is shortened.
また最も像面側に正レンズを配置することで、ある程度のテレフォト構成を維持しつつ、第3レンズ群L3の対称性を高めている。 Further, by arranging the positive lens closest to the image plane side, the symmetry of the third lens unit L3 is enhanced while maintaining a certain telephoto configuration.
これによって第3レンズ群L3内で歪曲収差を補正し、第3レンズ群L3をシフトして防振を行う際に発生する偏心歪曲収差の発生を低減している。 As a result, distortion is corrected in the third lens unit L3, and the occurrence of decentration distortion that occurs when the third lens unit L3 is shifted to perform image stabilization is reduced.
さらに各実施例では、軸上光線が高い位置を通る、開口絞りSPのすぐ後に位置する第3レンズ群L3の最も物体側の正レンズの1面を非球面形状としている。 Furthermore, in each embodiment, one surface of the positive lens closest to the object side of the third lens unit L3 positioned immediately after the aperture stop SP through which the on-axis light beam passes is aspherical.
これによって広角端から望遠端に至るズーム範囲全域に渡って球面収差とコマ収差を良好に補正している。 As a result, spherical aberration and coma are corrected well over the entire zoom range from the wide-angle end to the telephoto end.
次に本発明の数値実施例を示す。数値実施例においてiは物体側からの光学面の順序を示す。Riは第i面の曲率半径、Diは第i面と第i+1面の間の間隔、Niとνiは各々d線に対する第i番目の光学部材の屈折率とアッベ数である。 Next, numerical examples of the present invention will be shown. In the numerical examples, i indicates the order of the optical surfaces from the object side. Ri is the radius of curvature of the i-th surface, Di is the distance between the i-th surface and the (i + 1) -th surface, and Ni and νi are the refractive index and Abbe number of the i-th optical member with respect to the d-line, respectively.
非球面形状は光軸方向にX軸、光軸と垂直方向にH軸、光の進行方向を正としRを近軸曲率半径、Kを円錐定数、B,C,D,Eを各々非球面係数としたとき The aspherical shape is the X axis in the optical axis direction, the H axis in the direction perpendicular to the optical axis, the light traveling direction is positive, R is the paraxial radius of curvature, K is the conic constant, and B, C, D, and E are aspherical surfaces, respectively. When using coefficients
なる式で表している。 It is expressed by the following formula.
また、例えば「e−Z」の表示は「10−Z」を意味する。fは焦点距離、FnoはFナンバー、ωは半画角である。また前述の各条件式と数値実施例の関係を表1に示す。 Further, for example, the display of “e-Z” means “10 −Z ”. f is a focal length, Fno is an F number, and ω is a half angle of view. Table 1 shows the relationship between the above-described conditional expressions and numerical examples.
数値実施例 1
f= 7.74 〜 89.56 Fno= 2.88 〜 3.77 2ω=60.5゜〜 5.8゜
R 1 = 71.103 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 34.313 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -367.241 D 3 = 0.20
R 4 = 33.071 D 4 = 4.70 N 3 = 1.49700 ν3 = 81.5
R 5 = 300.263 D 5 = 可変
R 6 = 72.805 D 6 = 1.20 N 4 = 1.83400 ν4 = 37.2
R 7 = 10.237 D 7 = 4.84
R 8 = -38.863 D 8 = 0.90 N 5 = 1.60311 ν5 = 60.6
R 9 = 25.242 D 9 = 0.80
R10 = 19.034 D10 = 2.40 N 6 = 1.92286 ν6 = 18.9
R11 = 57.423 D11 = 可変
R12 = 開口絞り D12 = 可変
R13 =11.580(非球面)D13 = 3.00 N 7= 1.58313 ν7 = 59.4
R14 = -109.327 D14 = 2.80
R15 = 19.010 D15 = 0.80 N 8 = 1.84666 ν8 = 23.9
R16 = 9.941 D16 = 1.10
R17 = 49.134 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -160.488 D18 = 1.46
R19 = 固定絞り D19 = 可変
R20 = 25.636 D20 = 2.90 N10 = 1.69680 ν10 = 55.5
R21 = -33.447 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = -130.833 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
Numerical example 1
f = 7.74 to 89.56 Fno = 2.88 to 3.77 2ω = 60.5 ° to 5.8 °
R 1 = 71.103 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 34.313 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -367.241 D 3 = 0.20
R 4 = 33.071 D 4 = 4.70 N 3 = 1.49700 ν3 = 81.5
R 5 = 300.263 D 5 = Variable
R 6 = 72.805 D 6 = 1.20 N 4 = 1.83400 ν4 = 37.2
R 7 = 10.237 D 7 = 4.84
R 8 = -38.863 D 8 = 0.90 N 5 = 1.60311 ν5 = 60.6
R 9 = 25.242 D 9 = 0.80
R10 = 19.034 D10 = 2.40 N 6 = 1.92286 ν6 = 18.9
R11 = 57.423 D11 = variable
R12 = Aperture stop D12 = Variable
R13 = 11.580 (aspheric) D13 = 3.00 N 7 = 1.58313 ν7 = 59.4
R14 = -109.327 D14 = 2.80
R15 = 19.010 D15 = 0.80 N 8 = 1.84666 ν8 = 23.9
R16 = 9.941 D16 = 1.10
R17 = 49.134 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -160.488 D18 = 1.46
R19 = Fixed iris D19 = Variable
R20 = 25.636 D20 = 2.90 N10 = 1.69680 ν10 = 55.5
R21 = -33.447 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = -130.833 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
非球面係数
R14 k=-1.62191 B = 1.07376e-4 C = 7.99936e-6 D = 1.21422e-7
E=-4.73427e-10 A'=-4.49811e-5 B'=-2.53899e-5 C'=-1.45680e-6
数値実施例 2
f= 7.74 〜 89.56 Fno= 2.81 〜 3.85 2ω=63.1゜〜 5.8゜
R 1 = 73.236 D 1 = 1.70 N 1 = 1.74950 ν1 = 35.3
R 2 = 35.024 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -334.072 D 3 = 0.20
R 4 = 32.823 D 4 = 4.70 N 3 = 1.49700 ν3 = 81.5
R 5 = 147.896 D 5 = 可変
R 6 = 65.598 D 6 = 1.20 N 4 = 1.83481 ν4 = 42.7
R 7 = 9.932 D 7 = 4.62
R 8 = -51.567 D 8 = 0.90 N 5 = 1.66672 ν5 = 48.3
R 9 = 26.634 D 9 = 0.80
R10 = 18.316 D10 = 2.40 N 6 = 1.92286 ν6 = 18.9
R11 = 50.067 D11 = 可変
R12 = 開口絞り D12 = 可変
R13 =13.305(非球面)D13 = 3.20 N 7= 1.74330 ν7 = 49.3
R14 = -97.155 D14 = 2.80
R15 = 66.719 D15 = 0.80 N 8 = 1.84666 ν8 = 23.9
R16 = 11.629 D16 = 1.00
R17 = 27.560 D17 = 2.00 N 9 = 1.48749 ν9 = 70.2
R18 = -39.332 D18 = 1.46
R19 = 固定絞り D19 = 可変
R20 = 29.994 D20 = 2.80 N10 = 1.71300 ν10 = 53.9
R21 = -67.545 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = -167.492 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
Aspheric coefficient
R14 k = -1.62191 B = 1.07376e-4 C = 7.99936e-6 D = 1.21422e-7
E = -4.73427e-10 A '=-4.49811e-5 B' =-2.53899e-5 C '=-1.45680e-6
Numerical example 2
f = 7.74 to 89.56 Fno = 2.81 to 3.85 2ω = 63.1 ° to 5.8 °
R 1 = 73.236 D 1 = 1.70 N 1 = 1.74950 ν1 = 35.3
R 2 = 35.024 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -334.072 D 3 = 0.20
R 4 = 32.823 D 4 = 4.70 N 3 = 1.49700 ν3 = 81.5
R 5 = 147.896 D 5 = Variable
R 6 = 65.598 D 6 = 1.20 N 4 = 1.83481 ν4 = 42.7
R 7 = 9.932 D 7 = 4.62
R 8 = -51.567 D 8 = 0.90 N 5 = 1.66672 ν5 = 48.3
R 9 = 26.634 D 9 = 0.80
R10 = 18.316 D10 = 2.40 N 6 = 1.92286 ν6 = 18.9
R11 = 50.067 D11 = variable
R12 = Aperture stop D12 = Variable
R13 = 13.305 (Aspherical) D13 = 3.20 N 7 = 1.74330 ν7 = 49.3
R14 = -97.155 D14 = 2.80
R15 = 66.719 D15 = 0.80 N 8 = 1.84666 ν8 = 23.9
R16 = 11.629 D16 = 1.00
R17 = 27.560 D17 = 2.00 N 9 = 1.48749 ν9 = 70.2
R18 = -39.332 D18 = 1.46
R19 = Fixed iris D19 = Variable
R20 = 29.994 D20 = 2.80 N10 = 1.71300 ν10 = 53.9
R21 = -67.545 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = -167.492 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
非球面係数
R14 k= 1.51186 B = -6.85166e-5 C =-1.14823e-7 D =-1.46666e-7
E= 7.06620e-10 A'= -6.73836e-5 B'=-1.99923e-5 C'= 8.31856e-7
数値実施例 3
f= 7.74 〜 89.56 Fno= 2.84 〜 3.85 2ω=60.5゜〜 5.8゜
R 1 = 98.087 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 34.288 D 2 = 6.20 N 2 = 1.58913 ν2 = 61.1
R 3 = -261.565 D 3 = 0.20
R 4 = 31.838 D 4 = 4.70 N 3 = 1.49700 ν3 = 81.5
R 5 = 171.669 D 5 = 可変
R 6 = 65.128 D 6 = 1.20 N 4 = 1.83481 ν4 = 42.7
R 7 = 9.689 D 7 = 4.50
R 8 = -47.835 D 8 = 0.90 N 5 = 1.66672 ν5 = 48.3
R 9 = 26.668 D 9 = 0.80
R10 = 18.043 D10 = 2.51 N 6 = 1.92286 ν6 = 18.9
R11 = 49.765 D11 = 可変
R12 = 開口絞り D12 = 可変
R13 =13.970(非球面)D13 = 3.20 N 7 = 1.69350 ν7 = 53.2
R14 = -156.361 D14 = 2.80
R15 = 45.386 D15 = 0.80 N 8 = 1.84666 ν8 = 23.9
R16 = 13.298 D16 = 1.10
R17 = 45.390 D17 = 2.00 N 9 = 1.48749 ν9 = 70.2
R18 = -25.298 D18 = 1.46
R19 = 固定絞り D19 = 可変
R20 = 31.266 D20 = 2.80 N10 = 1.71300 ν10 = 53.9
R21 = -72.909 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 =-2269.673 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
Aspheric coefficient
R14 k = 1.51186 B = -6.85166e-5 C = -1.14823e-7 D = -1.46666e-7
E = 7.06620e-10 A '= -6.73836e-5 B' =-1.99923e-5 C '= 8.31856e-7
Numerical example 3
f = 7.74 to 89.56 Fno = 2.84 to 3.85 2ω = 60.5 ° to 5.8 °
R 1 = 98.087 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 34.288 D 2 = 6.20 N 2 = 1.58913 ν2 = 61.1
R 3 = -261.565 D 3 = 0.20
R 4 = 31.838 D 4 = 4.70 N 3 = 1.49700 ν3 = 81.5
R 5 = 171.669 D 5 = variable
R 6 = 65.128 D 6 = 1.20 N 4 = 1.83481 ν4 = 42.7
R 7 = 9.689 D 7 = 4.50
R 8 = -47.835 D 8 = 0.90 N 5 = 1.66672 ν5 = 48.3
R 9 = 26.668 D 9 = 0.80
R10 = 18.043 D10 = 2.51 N 6 = 1.92286 ν6 = 18.9
R11 = 49.765 D11 = variable
R12 = Aperture stop D12 = Variable
R13 = 13.970 (Aspherical) D13 = 3.20 N 7 = 1.69350 ν7 = 53.2
R14 = -156.361 D14 = 2.80
R15 = 45.386 D15 = 0.80 N 8 = 1.84666 ν8 = 23.9
R16 = 13.298 D16 = 1.10
R17 = 45.390 D17 = 2.00 N 9 = 1.48749 ν9 = 70.2
R18 = -25.298 D18 = 1.46
R19 = Fixed iris D19 = Variable
R20 = 31.266 D20 = 2.80 N10 = 1.71300 ν10 = 53.9
R21 = -72.909 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = -2269.673 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
非球面係数
R14 k= 5.41434e-1 B =-4.04284e-5 C = 1.90402e-6 D =-7.97902e-8
E= 6.69964e-10 A'=-2.76268e-5 B'=-1.51338e-5 C'= 2.48920e-7
数値実施例 4
f= 7.74 〜 89.57 Fno= 2.85 〜 3.85 2ω=60.5゜〜 5.8゜
R 1 = 67.282 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 35.500 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -292.159 D 3 = 0.20
R 4 = 32.129 D 4 = 4.70 N 3 = 1.43875 ν3 = 95.0
R 5 = 194.324 D 5 = 可変
R 6 = 70.193 D 6 = 1.20 N 4 = 1.80400 ν4 = 46.6
R 7 = 9.722 D 7 = 5.05
R 8 = -37.964 D 8 = 0.90 N 5 = 1.69680 ν5 = 55.5
R 9 = 26.475 D 9 = 0.20
R10 = 18.117 D10 = 2.70 N 6 = 1.84666 ν6 = 23.9
R11 = 140.853 D11 = 可変
R12 = 開口絞り D12 = 可変
R13 =13.256(非球面)D13 = 3.00 N 7= 1.66910 ν7 = 55.4
R14 =-1005.721 D14 = 2.40
R15 = 17.089 D15 = 0.80 N 8 = 1.92286 ν8 = 18.9
R16 = 10.878 D16 = 1.30
R17 = -243.259 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -26.163 D18 = 1.46
R19 = 固定絞り D19 = 可変
R20 = 28.205 D20 = 2.70 N10 = 1.69680 ν10 = 55.5
R21 = -84.898 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = 1702.403 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
Aspheric coefficient
R14 k = 5.41434e-1 B = -4.04284e-5 C = 1.90402e-6 D = -7.97902e-8
E = 6.69964e-10 A '=-2.76268e-5 B' =-1.51338e-5 C '= 2.48920e-7
Numerical example 4
f = 7.74 to 89.57 Fno = 2.85 to 3.85 2ω = 60.5 ° to 5.8 °
R 1 = 67.282 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 35.500 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -292.159 D 3 = 0.20
R 4 = 32.129 D 4 = 4.70 N 3 = 1.43875 ν3 = 95.0
R 5 = 194.324 D 5 = Variable
R 6 = 70.193 D 6 = 1.20 N 4 = 1.80400 ν4 = 46.6
R 7 = 9.722 D 7 = 5.05
R 8 = -37.964 D 8 = 0.90 N 5 = 1.69680 ν5 = 55.5
R 9 = 26.475 D 9 = 0.20
R10 = 18.117 D10 = 2.70 N 6 = 1.84666 ν6 = 23.9
R11 = 140.853 D11 = variable
R12 = Aperture stop D12 = Variable
R13 = 13.256 (Aspherical) D13 = 3.00 N 7 = 1.66910 ν7 = 55.4
R14 = -1005.721 D14 = 2.40
R15 = 17.089 D15 = 0.80 N 8 = 1.92286 ν8 = 18.9
R16 = 10.878 D16 = 1.30
R17 = -243.259 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -26.163 D18 = 1.46
R19 = Fixed iris D19 = Variable
R20 = 28.205 D20 = 2.70 N10 = 1.69680 ν10 = 55.5
R21 = -84.898 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = 1702.403 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
非球面係数
R14 k=-8.18503e-1 B = 5.02929e-5 C = 8.40041e-6 D = 9.89551e-8
E=-2.77395e-10 A'=-6.11176e-5 B'=-2.89954e-5 C'=-1.35505e-6
数値実施例 5
f= 7.74 〜 89.57 Fno= 2.85 〜 3.85 2ω=60.5゜〜 5.8゜
R 1 = 82.622 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 34.132 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -400.896 D 3 = 0.20
R 4 = 34.163 D 4 = 4.70 N 3 = 1.56907 ν3 = 71.3
R 5 = 310.564 D 5 = 可変
R 6 = 59.934 D 6 = 1.20 N 4 = 1.80400 ν4 = 46.6
R 7 = 9.501 D 7 = 4.99
R 8 = -39.158 D 8 = 0.90 N 5 = 1.69680 ν5 = 55.5
R 9 = 25.360 D 9 = 0.20
R10 = 17.416 D10 = 2.70 N 6 = 1.84666 ν6 = 23.9
R11 = 113.553 D11 = 可変
R12 = 開口絞り D12 = 可変
R13 =12.962(非球面)D13 = 3.00 N 7= 1.66910 ν7 = 55.4
R14 = -519.408 D14 = 2.40
R15 = 16.220 D15 = 0.80 N 8 = 1.92286 ν8 = 18.9
R16 = 10.370 D16 = 1.50
R17 = -203.762 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -28.323 D18 = 1.46
R19 = 固定絞り D19 = 可変
R20 = 26.261 D20 = 2.40 N10 = 1.69680 ν10 = 55.5
R21 = -97.993 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = 367.979 D22 =10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
Aspheric coefficient
R14 k = -8.18503e-1 B = 5.02929e-5 C = 8.40041e-6 D = 9.89551e-8
E = -2.77395e-10 A '=-6.11176e-5 B' =-2.89954e-5 C '=-1.35505e-6
Numerical example 5
f = 7.74 to 89.57 Fno = 2.85 to 3.85 2ω = 60.5 ° to 5.8 °
R 1 = 82.622 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 34.132 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -400.896 D 3 = 0.20
R 4 = 34.163 D 4 = 4.70 N 3 = 1.56907 ν3 = 71.3
R 5 = 310.564 D 5 = Variable
R 6 = 59.934 D 6 = 1.20 N 4 = 1.80400 ν4 = 46.6
R 7 = 9.501 D 7 = 4.99
R 8 = -39.158 D 8 = 0.90 N 5 = 1.69680 ν5 = 55.5
R 9 = 25.360 D 9 = 0.20
R10 = 17.416 D10 = 2.70 N 6 = 1.84666 ν6 = 23.9
R11 = 113.553 D11 = variable
R12 = Aperture stop D12 = Variable
R13 = 12.962 (Aspherical) D13 = 3.00 N 7 = 1.66910 ν7 = 55.4
R14 = -519.408 D14 = 2.40
R15 = 16.220 D15 = 0.80 N 8 = 1.92286 ν8 = 18.9
R16 = 10.370 D16 = 1.50
R17 = -203.762 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -28.323 D18 = 1.46
R19 = Fixed iris D19 = Variable
R20 = 26.261 D20 = 2.40 N10 = 1.69680 ν10 = 55.5
R21 = -97.993 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = 367.979 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
非球面係数
R14 k=-9.19156e-1 B = 5.80487e-5 C = 8.36018e-6 D = 8.43578e-8
E=-2.18436e-10 A'=-5.16908e-5 B'=-3.01793e-5 C'=-1.24856e-6
数値実施例 6
f= 7.74 〜 89.56 Fno= 2.89 〜 3.32 2ω=60.5゜〜 5.8゜
R 1 = 81.007 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 33.554 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -434.240 D 3 = 0.20
R 4 = 33.990 D 4 = 4.70 N 3 = 1.56907 ν3 = 71.3
R 5 = 371.485 D 5 = 可変
R 6 = 66.358 D 6 = 1.20 N 4 = 1.80400 ν4 = 46.6
R 7 = 9.527 D 7 = 5.03
R 8 = -30.907 D 8 = 0.90 N 5 = 1.69680 ν5 = 55.5
R 9 = 29.623 D 9 = 0.20
R10 = 18.852 D10 = 2.70 N 6 = 1.84666 ν6 = 23.9
R11 = 208.598 D11 = 可変
R12 = 開口絞り D12 = 1.39
R13 =12.793(非球面)D13 = 3.00 N 7= 1.66910 ν7 = 55.4
R14 = 168.066 D14 = 2.40
R15 = 15.421 D15 = 0.80 N 8 = 1.92286 ν8 = 18.9
R16 = 10.331 D16 = 1.50
R17 = -713.649 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -26.703 D18 = 1.46
R19 = 固定絞り D19 = 可変
R20 = 26.661 D20 = 2.40 N10 = 1.69680 ν10 = 55.5
R21 = -74.757 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = 390.914 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
Aspheric coefficient
R14 k = -9.19156e-1 B = 5.80487e-5 C = 8.36018e-6 D = 8.43578e-8
E = -2.18436e-10 A '=-5.16908e-5 B' =-3.01793e-5 C '=-1.24856e-6
Numerical example 6
f = 7.74 to 89.56 Fno = 2.89 to 3.32 2ω = 60.5 ° to 5.8 °
R 1 = 81.007 D 1 = 1.70 N 1 = 1.83400 ν1 = 37.2
R 2 = 33.554 D 2 = 6.20 N 2 = 1.48749 ν2 = 70.2
R 3 = -434.240 D 3 = 0.20
R 4 = 33.990 D 4 = 4.70 N 3 = 1.56907 ν3 = 71.3
R 5 = 371.485 D 5 = Variable
R 6 = 66.358 D 6 = 1.20 N 4 = 1.80400 ν4 = 46.6
R 7 = 9.527 D 7 = 5.03
R 8 = -30.907 D 8 = 0.90 N 5 = 1.69680 ν5 = 55.5
R 9 = 29.623 D 9 = 0.20
R10 = 18.852 D10 = 2.70 N 6 = 1.84666 ν6 = 23.9
R11 = 208.598 D11 = variable
R12 = Aperture D12 = 1.39
R13 = 12.793 (Aspherical) D13 = 3.00 N 7 = 1.66910 ν7 = 55.4
R14 = 168.066 D14 = 2.40
R15 = 15.421 D15 = 0.80 N 8 = 1.92286 ν8 = 18.9
R16 = 10.331 D16 = 1.50
R17 = -713.649 D17 = 1.80 N 9 = 1.48749 ν9 = 70.2
R18 = -26.703 D18 = 1.46
R19 = Fixed iris D19 = Variable
R20 = 26.661 D20 = 2.40 N10 = 1.69680 ν10 = 55.5
R21 = -74.757 D21 = 0.70 N11 = 1.84666 ν11 = 23.9
R22 = 390.914 D22 = 10.0
R23 = ∞ D23 = 1.00 N12 = 1.516330 ν12 = 64.1
R24 = ∞
非球面係数
R14 k=-8.86533e-1 B = 6.00603e-5 C = 8.32118e-6 D = 8.48513e-8
E=-1.38375e-10 A'=-5.99159e-5 B'=-2.89432e-5 C'=-1.27958e-6
Aspheric coefficient
R14 k = -8.86533e-1 B = 6.00603e-5 C = 8.32118e-6 D = 8.48513e-8
E = -1.38375e-10 A '=-5.99159e-5 B' =-2.89432e-5 C '=-1.27958e-6
次に、数値実施例1〜6のズームレンズを撮影光学系とした撮像装置の実施例を図25を用いて説明する。 Next, an embodiment of an image pickup apparatus using the zoom lenses of Numerical Examples 1 to 6 as a photographing optical system will be described with reference to FIG.
図25において、10はビデオカメラやデジタルスチルカメラ等の撮像装置本体、11は本発明のズームレンズによって構成された撮影光学系である。 In FIG. 25, reference numeral 10 denotes an image pickup apparatus body such as a video camera or a digital still camera, and 11 denotes a photographing optical system constituted by the zoom lens of the present invention.
12は撮影光学系11によって被写体像を受光するCCDやCMOS等で構成される固体撮像素子、13は撮像素子12が受光した被写体像に関する情報を記録するメモリ、14は不図示の表示素子に表示された被写体像を観察するためのファインダーである。 Reference numeral 12 denotes a solid-state imaging device composed of a CCD, CMOS, or the like that receives a subject image by the photographing optical system 11, reference numeral 13 denotes a memory that records information about the subject image received by the imaging element 12, and reference numeral 14 denotes a display element (not shown). It is a finder for observing the subject image.
上記表示素子は液晶パネル等によって構成され、撮像素子12上に形成された被写体像が表示される。 The display element is constituted by a liquid crystal panel or the like, and a subject image formed on the image sensor 12 is displayed.
15は前記ファインダーと同等の機能を有する液晶表示パネルである。このように本発明のズームレンズをビデオカメラ等の撮像装置に適用することにより、小型で高い光学性能を有する撮像装置を実現している。 Reference numeral 15 denotes a liquid crystal display panel having a function equivalent to that of the finder. Thus, by applying the zoom lens of the present invention to an image pickup apparatus such as a video camera, a small-size image pickup apparatus having high optical performance is realized.
L1 第1レンズ群
L2 第2レンズ群
L3 第3レンズ群
L4 第4レンズ群
d d線
g g線
ΔM メリジオナル像面
ΔS サジタル像面
SP 絞り
FP フレアーカット絞り
IP 結像面
G CCDのフェースプレートやローパスフィルター等のガラスブロック
ω 半画角
Fno Fナンバー
L1 1st lens group L2 2nd lens group L3 3rd lens group L4 4th lens group d d line g g line ΔM meridional image plane ΔS sagittal image plane SP aperture FP flare cut aperture IP imaging surface G CCD faceplate Glass block such as low-pass filter ω Half angle of view Fno F number
Claims (9)
70<νd3
0<νd3−νd2<30.0
2.0<f1a/f1b<20.0
なる条件を満足することを特徴とするズームレンズ。 In order from the object side to the image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power. a more composed zoom lens in the telephoto end than at the wide-angle end, the first lens group is located on the object side, the interval between the second lens group and the first lens group becomes large, the first the distance between the third lens group and the second lens group becomes small, the fourth lens group in zooming is moved along a locus convex to the object side, the fourth lens group is moved during focusing, the first lens group includes, in order from the object side to the image side, a negative lens G11, a positive lens G12, and a positive lens G13, the Abbe number of the positive lens G12 material vd2, the Abbe number of the material of the positive lens G13 vd3, wherein wherein the negative lens G11 positive When the combined focal length of the lens G12 f1a, the focal length of the positive lens G13 and f1b,
70 <νd3
0 <νd3-νd2 <30.0
2.0 <f1a / f1b <20.0
A zoom lens characterized by satisfying the following conditions:
0.52<θgF
なる条件を満足することを特徴とする請求項1のズームレンズ。 When the partial dispersion ratio of the material of the positive lens G13 is θgF,
0.52 <θgF
The zoom lens according to claim 1, wherein the following condition is satisfied.
1.0<(R31+R32)/(R32−R31)<2.0
なる条件を満足することを特徴とする請求項1から3のいずれか1項に記載のズームレンズ。 When the curvature radii of the object side and image side surfaces of the positive lens G13 are R31 and R32, respectively.
1.0 <(R31 + R32) / ( R32 − R31 ) <2.0
The zoom lens according to claim 1, wherein the following condition is satisfied.
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JP5362757B2 (en) * | 2010-03-05 | 2013-12-11 | Hoya株式会社 | High zoom ratio zoom lens system |
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US8995064B2 (en) | 2011-08-22 | 2015-03-31 | Nikon Corporation | Zoom lens, imaging apparatus, and method for manufacturing zoom lens |
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