JP2018180366A - Image pickup optical system and image pickup apparatus using the same - Google Patents
Image pickup optical system and image pickup apparatus using the same Download PDFInfo
- Publication number
- JP2018180366A JP2018180366A JP2017081260A JP2017081260A JP2018180366A JP 2018180366 A JP2018180366 A JP 2018180366A JP 2017081260 A JP2017081260 A JP 2017081260A JP 2017081260 A JP2017081260 A JP 2017081260A JP 2018180366 A JP2018180366 A JP 2018180366A
- Authority
- JP
- Japan
- Prior art keywords
- lens
- optical system
- imaging optical
- positive lens
- cemented
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Lenses (AREA)
Abstract
【課題】大口径比で色収差を良好に補正し、高画質でしかもボケ味の良い画像が容易に得られる撮像光学系を得る。【解決手段】物体側から像側へ順に配置された前群、開口絞りＳＰ、後群より構成される撮像光学系Ｌ０において、前群に含まれ開口絞りＳＰに隣接して配置されたレンズは、像側のレンズ面が凹形状であり、後群の最も物体側には接合レンズＬＲが配置され、接合レンズＬＲは物体側のレンズ面が凹形状であり、負レンズＬＲＮと正レンズＬＲＰが接合されて構成されており、負レンズＬＲＮと正レンズＬＲＰの材料のアッベ数を各々νｄｎＲ、νｄｐＲとし、負レンズＬＲＮと正レンズＬＲＰの材料の部分分散比を各々θｇＦｎＲ、θｇＦｐＲとしたとき以下の式を満たす。θｇＦｎＲ−（−０．００２４０νｄｎＲ＋０．６６９４）＜０．０、３０．０＜νｄｎＲ、０．０＜θｇＦｐＲ−（−０．０００８３νｄｐＲ＋０．５９８１）、４２．０＜νｄｐＲ＜８０．０【選択図】図１PROBLEM TO BE SOLVED: To obtain an imaging optical system capable of satisfactorily correcting chromatic aberration with a large aperture ratio and easily obtaining an image having high image quality and good blur. SOLUTION: In an imaging optical system L0 composed of a front group, an aperture aperture SP, and a rear group arranged in order from an object side to an image side, a lens included in the front group and arranged adjacent to the aperture aperture SP , The lens surface on the image side is concave, the junction lens LR is arranged on the most object side of the rear group, the lens surface on the object side of the junction lens LR is concave, and the negative lens LRN and the positive lens LRP are It is configured by being joined, and when the abbreviation numbers of the materials of the negative lens LRN and the positive lens LRP are νdnR and νdpR, respectively, and the partial dispersion ratios of the materials of the negative lens LRN and the positive lens LRP are θgFnR and θgFpR, respectively, the following. Satisfy the formula. θgFnR- (-0.00240νdnR + 0.6694) <0.0, 30.0 <νdnR, 0.0 <θgFpR- (-0.00083νdpR + 0.5981), 42.0 <νdpR <80.0 [selection diagram] 1
Description
本発明は撮像光学系に関し、特に一眼レフカメラ、デジタルスチルカメラ、フィルム用カメラ、ビデオカメラ、監視用カメラ等の撮像装置に好適なものである。 The present invention relates to an imaging optical system, and is particularly suitable for an imaging apparatus such as a single-lens reflex camera, a digital still camera, a film camera, a video camera, and a surveillance camera.
近年、撮像素子を用いた撮像装置は小型化されるとともに、画質の高画質化が進んでいる。特に一眼レフカメラにおいては、撮像時の画質の高画質化に加え、画像のボケ味が良いことが要求されている。これらの要求を満足するために、近年はＦｎｏ（Ｆナンバー）を明るくし、ボケ量のコントロールが出来るようにした大口径比の撮像光学系が提案されている。この大口径化を満足する撮像光学系のレンズタイプとしては、例えばダブルガウスタイプが知られている。 2. Description of the Related Art In recent years, imaging devices using imaging elements have been miniaturized, and image quality has been improved. In particular, in the single-lens reflex camera, in addition to the image quality improvement at the time of imaging, it is required that the image has a good blur. In order to satisfy these requirements, an imaging optical system with a large aperture ratio has recently been proposed which brightens the Fno (F number) and enables control of the amount of blur. For example, a double Gaussian type is known as a lens type of an imaging optical system that satisfies this large aperture.
高画質化を図りつつ、ボケ味をきれいにするためには、色収差を軽減し、色滲みを抑えることが必要になってくる。ダブルガウスタイプの撮像光学系は、大口径比化が容易であるが、色収差を補正しつつ像面湾曲を良好に補正することが難しい。このため、ダブルガウスタイプを変形させて色収差と像面湾曲等の諸収差を良好に補正するようにした撮像光学系が提案されている（特許文献１、２）。特許文献１、２は開口絞りの物体側に配置するレンズの硝材及び屈折力配置等を適切に構成することで高画質化を図りつつ、大口径比化を図っている。 It is necessary to reduce chromatic aberration and suppress color blur in order to clear the blur while achieving high image quality. In the double Gaussian type imaging optical system, it is easy to increase the aperture ratio, but it is difficult to correct the curvature of field favorably while correcting the chromatic aberration. For this reason, imaging optical systems have been proposed in which the double Gaussian type is deformed to correct various aberrations such as chromatic aberration and curvature of field favorably (Japanese Patent Application Laid-Open Nos. 2001-345, and 2002-39118). In Patent Documents 1 and 2, a large aperture ratio is achieved while achieving high image quality by appropriately configuring the glass material and refractive power arrangement and the like of the lens disposed on the object side of the aperture stop.
ダブルガウスタイプの撮像光学系は大口径比化が容易で、しかも物体距離の変動に対する収差変動が比較的少ないという特徴がある。しかしながら大口径比化を図りつつ、色収差を低減し、高画質でしかも全系の小型化を図るには、撮像光学系を構成する各レンズの材料を適切に設定することが重要になってくる。例えば屈折率、アッベ数、部分分散比等を適切に選択した材料のレンズを光路中の適切な位置に用いることが重要になってくる。特に色収差を良好に補正し、高画質でボケ味の良い画像を得るには開口絞りに隣接して物体側と像側に配置されたレンズの形状や材料等を適切に設定することが重要になってくる。 The double Gaussian type imaging optical system is characterized in that a large aperture ratio can be easily obtained, and moreover, aberration fluctuation with respect to object distance fluctuation is relatively small. However, in order to reduce chromatic aberration, achieve high image quality, and miniaturize the entire system while achieving a large aperture ratio, it is important to appropriately set the materials of the respective lenses constituting the imaging optical system. . For example, it is important to use a lens of a material whose refractive index, Abbe number, partial dispersion ratio, etc. are appropriately selected at an appropriate position in the optical path. In particular, it is important to appropriately set the shape, material, etc. of the lenses disposed on the object side and the image side adjacent to the aperture stop in order to correct the chromatic aberration well and obtain an image with high image quality and good blur. It will come.
本発明は、大口径比で色収差を良好に補正し、高画質でしかもボケ味の良い画像が容易に得られる撮像光学系の提供を目的とする。 An object of the present invention is to provide an imaging optical system which can correct chromatic aberration well with a large aperture ratio and easily obtain an image with high image quality and good blur.
本発明の撮像光学系は、物体側から像側へ順に配置された前群、開口絞り、後群より構成される撮像光学系において、
前記前群に含まれ前記開口絞りに隣接して配置されたレンズは、像側のレンズ面が凹形状であり、前記後群の最も物体側には接合レンズＬＲが配置され、
前記接合レンズＬＲは物体側のレンズ面が凹形状であり、負レンズＬＲＮと正レンズＬＲＰが接合されて構成されており、
前記負レンズＬＲＮと前記正レンズＬＲＰの材料のアッベ数を各々νｄｎＲ、νｄｐＲ、前記負レンズＬＲＮと前記正レンズＬＲＰの材料の部分分散比を各々θｇＦｎＲ、θｇＦｐＲとするとき、
θｇＦｎＲ−（−０．００２４０νｄｎＲ＋０．６６９４）＜０．０
３０．０＜νｄｎＲ
０．０＜θｇＦｐＲ−（−０．０００８３νｄｐＲ＋０．５９８１）
４２．０＜νｄｐＲ＜８０．０
なる条件式を満足することを特徴としている。
An imaging optical system according to the present invention is an imaging optical system including a front group, an aperture stop, and a rear group disposed in order from an object side to an image side,
The lens included in the front group and disposed adjacent to the aperture stop has a concave lens surface on the image side, and the cemented lens LR is disposed on the most object side of the rear group.
The cemented lens LR has a concave lens surface on the object side, and is constructed by cementing a negative lens LRN and a positive lens LRP.
Assuming that the Abbe numbers of materials of the negative lens LRN and the positive lens LRP are dndnR, dpdpR, and partial dispersion ratios of the materials of the negative lens LRN and the positive lens LRP are θgFnR, θgFpR, respectively.
θ g F n R − (−0.00 240 dn d n R + 0.6 694) <0.0
30.0 <νdnR
0.0 <θgFpR − (− 0.00083νdpR + 0.5981)
42.0 <νdpR <80.0
It is characterized by satisfying the following conditional expression.
本発明によれば、大口径比で色収差を良好に補正し、高画質でしかもボケ味の良い画像が容易に得られる撮像光学系が得られる。 According to the present invention, it is possible to obtain an imaging optical system that can correct chromatic aberration well with a large aperture ratio and easily obtain an image with high image quality and good blur.
以下、図面を用いて本発明の撮像光学系及びそれを有する撮像装置の実施例について説明する。本発明の撮像光学系は、物体側から像側へ順に配置された前群、開口絞り、後群より構成される。前群に含まれ開口絞りに隣接して配置されたレンズは、像側のレンズ面が凹形状であり、後群の最も物体側には接合レンズＬＲを配置している。接合レンズＬＲは物体側のレンズ面が凹形状であり、負レンズＬＲＮと正レンズＬＲＰが接合されて構成されている。 Hereinafter, embodiments of the imaging optical system of the present invention and an imaging apparatus having the same will be described with reference to the drawings. The imaging optical system of the present invention is composed of a front group, an aperture stop, and a rear group arranged in order from the object side to the image side. The lens included in the front group and disposed adjacent to the aperture stop has a concave lens surface on the image side, and the cemented lens LR is disposed on the most object side of the rear group. The cemented lens LR has a concave lens surface on the object side, and is constructed by cementing a negative lens LRN and a positive lens LRP.
接合レンズＬＲは物体側から像側へ順に配置された正レンズＬＲＰ、負レンズＬＲＮより構成される。または接合レンズＬＲは物体側から像側へ順に配置された負レンズＬＲＮ、正レンズＬＲＰより構成される。前群は開口絞りに隣接して接合レンズＬＦを有し、接合レンズＬＦは物体側から像側へ順に配置された正レンズＬＦＰと負レンズＬＦＮより構成される。 The cemented lens LR is composed of a positive lens LRP and a negative lens LRN, which are disposed in order from the object side to the image side. Alternatively, the cemented lens LR is composed of a negative lens LRN and a positive lens LRP, which are disposed in order from the object side to the image side. The front group has a cemented lens LF adjacent to the aperture stop, and the cemented lens LF is composed of a positive lens LFP and a negative lens LFN arranged in order from the object side to the image side.
図１は本発明の実施例１の無限遠に合焦（フォーカス）しているときのレンズ断面図である。図２（Ａ）、（Ｂ）は本発明の実施例１の無限遠と至近（撮像倍率−０．１８８）に合焦しているときの縦収差図である。実施例１はＦナンバー１．４５、撮像画角４５．８度の撮像光学系である。 FIG. 1 is a lens cross-sectional view when focusing at infinity according to the first embodiment of the present invention. FIGS. 2A and 2B are longitudinal aberration diagrams when focusing at infinity and at close distance (imaging magnification −0.188) according to the first embodiment of the present invention. The first embodiment is an imaging optical system having an f-number of 1.45 and an imaging angle of view of 45.8 degrees.
図３は本発明の実施例２の無限遠に合焦しているときのレンズ断面図である。図４（Ａ）、（Ｂ）は本発明の実施例２の無限遠と至近（撮像倍率−０．１７３）に合焦しているときの縦収差図である。実施例２はＦナンバー１．４５、撮像画角４６．２４度の撮像光学系である。 FIG. 3 is a lens cross-sectional view when focusing at infinity according to a second embodiment of the present invention. FIGS. 4A and 4B are longitudinal aberration diagrams when focusing on infinity and close range (imaging magnification of −0.173) according to the second embodiment of the present invention. The second embodiment is an imaging optical system having an f-number of 1.45 and an imaging angle of view of 46.24 degrees.
図５は本発明の実施例３の無限遠に合焦しているときのレンズ断面図である。図６（Ａ）、（Ｂ）は本発明の実施例３の無限遠と至近（撮像倍率−０．１８８）に合焦しているときの縦収差図である。実施例３はＦナンバー１．４５、撮像画角４５．８度の撮像光学系である。 FIG. 5 is a cross-sectional view of a lens when focused at infinity according to a third embodiment of the present invention. FIGS. 6A and 6B are longitudinal aberration diagrams when focusing on infinity and close range (imaging magnification −0.188) according to the third embodiment of the present invention. The third embodiment is an imaging optical system having an f-number of 1.45 and an imaging angle of view of 45.8 degrees.
図７は本発明の実施例４の無限遠に合焦しているときのレンズ断面図である。図８（Ａ）、（Ｂ）は本発明の実施例４の無限遠と至近（撮像倍率−０．１８８）に合焦しているときの縦収差図である。実施例４はＦナンバー１．４５、撮像画角４５．７２度の撮像光学系である。 FIG. 7 is a lens cross-sectional view when focusing at infinity according to the fourth embodiment of the present invention. FIGS. 8A and 8B are longitudinal aberration diagrams when focusing at infinity and at close distance (imaging magnification −0.188) according to the fourth embodiment of the present invention. The fourth embodiment is an imaging optical system having an f-number of 1.45 and an imaging angle of view of 45.72 degrees.
図９は本発明の実施例５の無限遠に合焦しているときのレンズ断面図である。図１０（Ａ）、（Ｂ）は本発明の実施例５の無限遠と至近（撮像倍率−０．１０１）に合焦しているときの縦収差図である。実施例５はＦナンバー１．４５、撮像画角４５．５度の撮像光学系である。 FIG. 9 is a cross-sectional view of a lens when focused at infinity according to a fifth embodiment of the present invention. FIGS. 10A and 10B are longitudinal aberration diagrams when focusing at infinity and at close distance (imaging magnification −0.101) according to the fifth embodiment of the present invention. The fifth embodiment is an imaging optical system having an f-number of 1.45 and an imaging angle of view of 45.5 degrees.
図１１は本発明の実施例６の無限遠に合焦しているときのレンズ断面図である。図１２（Ａ）、（Ｂ）は本発明の実施例６の無限遠と至近（撮像倍率−０．１８７）に合焦しているときの縦収差図である。実施例６はＦナンバー１．４５、撮像画角４６．０４度の撮像光学系である。図１３は本発明の撮像装置の要部概略図である。 FIG. 11 is a lens sectional view when focusing at infinity according to the sixth embodiment of the present invention. FIGS. 12A and 12B are longitudinal aberration diagrams when focusing at infinity and at close distance (imaging magnification −0.187) according to the sixth embodiment of the present invention. The sixth embodiment is an imaging optical system having an f-number of 1.45 and an imaging angle of view of 46.04 degrees. FIG. 13 is a schematic view of the essential parts of the imaging device of the present invention.
本発明の撮像光学系はデジタルカメラやビデオカメラ、放送用カメラ、監視用カメラ、銀塩写真用カメラ等の撮像装置に用いられる。 The imaging optical system of the present invention is used in an imaging apparatus such as a digital camera, a video camera, a broadcast camera, a surveillance camera, a silver halide photographic camera, and the like.
実施例１乃至４、６に対応する図１、図３、図５、図７、図１１のレンズ断面図において、左方が被写体側で、右方が像側である。レンズ断面図において、Ｌ０は撮像光学系である。Ｌ１は正の屈折力の第１レンズ群、Ｌ２は正の屈折力の第２レンズ群である。ＳＰは開口絞りであり、第１レンズ群Ｌ１内に配置しており、フォーカシングに際して第１レンズ群Ｌ１と一体的に（同じ軌跡で）移動する。開口絞りＳＰよりも物体側のレンズが前群、開口絞りＳＰより像側のレンズが後群である。 In the lens sectional views of FIGS. 1, 3, 5, 7, and 11 corresponding to the first to fourth and sixth embodiments, the left side is the object side and the right side is the image side. In the lens sectional view, L0 is an imaging optical system. L1 is a first lens group of positive refractive power, and L2 is a second lens group of positive refractive power. An aperture stop SP is disposed in the first lens unit L1 and moves integrally (in the same locus) with the first lens unit L1 during focusing. The lens on the object side of the aperture stop SP is the front group, and the lens on the image side of the aperture stop SP is the rear group.
実施例５の図９のレンズ断面図において、左方が被写体側で、右方が像側である。レンズ断面図において、Ｌ０は撮像光学系である。Ｌ１は正の屈折力の第１レンズ群である。ＳＰは開口絞りであり、第１レンズ群Ｌ１内に配置しており、フォーカシングに際して第１レンズ群Ｌ１と一体的に移動する。開口絞りＳＰよりも物体側のレンズが前群、開口絞りＳＰより像側のレンズが後群である。ＩＰは像面であり、デジタルスチルカメラやビデオカメラの撮像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の撮像面が、銀塩フィルム用カメラのときはフィルム面に相当する。 In the lens sectional view of FIG. 9 of the fifth embodiment, the left side is the object side and the right side is the image side. In the lens sectional view, L0 is an imaging optical system. L1 is a first lens group of positive refractive power. An aperture stop SP is disposed in the first lens unit L1, and moves integrally with the first lens unit L1 during focusing. The lens on the object side of the aperture stop SP is the front group, and the lens on the image side of the aperture stop SP is the rear group. IP is an image plane, and when used as an imaging optical system of a digital still camera or video camera, the imaging surface of a solid-state imaging device such as a CCD sensor or CMOS sensor corresponds to a film surface when a silver halide film camera Do.
収差図において、ＦｎｏはＦナンバーである。ωは半画角（度）である。また球面収差図において実線のｄはｄ線（波長５８７．６ｎｍ）、二点鎖線のｇはｇ線（波長４３５．８ｎｍ）である。非点収差図で点線のΔＭはｄ線におけるメリディオナル像面、実線のΔＳはｄ線におけるサジタル像面である。歪曲収差図はｄ線について示している。倍率色収差図において二点鎖線のｇはｇ線である。後述する数値データをｍｍ単位で表したとき縦収差図において、球面収差は０．２５ｍｍ、非点収差は０．２５ｍｍ、歪曲は２％、倍率色収差は０．０３ｍｍのスケールで描かれている。 In the aberration diagrams, Fno is an F number. ω is a half angle of view (degree). Further, in the spherical aberration diagram, d in the solid line is d-line (wavelength 587.6 nm), and g in the two-dot chain line is g-line (wavelength 435.8 nm). In the astigmatism diagram, dotted line ΔM is a meridional image plane at d-line, and solid line ΔS is a sagittal image plane at d-line. The distortion diagram is shown for the d-line. In the magnification chromatic aberration diagram, g in a two-dot chain line is a g-line. When numerical data to be described later is expressed in mm, in the longitudinal aberration diagram, the spherical aberration is 0.25 mm, the astigmatism is 0.25 mm, the distortion is 2%, and the lateral chromatic aberration is 0.03 mm.
本発明の撮像光学系Ｌ０は、Ｆ１．４（Ｆナンバー）程度の大口径でありながら色収差を軽減し高画質かつ全系が小型でボケ味のきれいな像が容易に得られる。撮像光学系Ｌ０を大口径化するためには、特にダブルガウスタイプを用いることが有効である。ダブルガウスタイプはレンズ構成を開口絞りに対して略対称配置としているため、コマ収差や歪曲収差等を良好に補正することが容易となる。 The imaging optical system L0 according to the present invention has a large aperture of about F1.4 (F number), reduces chromatic aberration, easily achieves high image quality, a small size of the whole system, and a beautifully blurred image. In order to increase the aperture of the imaging optical system L0, it is particularly effective to use a double Gaussian type. In the double Gaussian type, the lens configuration is substantially symmetrical with respect to the aperture stop, so that coma and distortion can be easily corrected well.
また、レンズの材料に高屈折率硝材を使用することで球面収差を良好に補正することが容易となる。しかしながらダブルガウスタイプは軸上色収差の補正が難しく、これを補正するためにはレンズ構成をダブルガウスタイプから変形させ、適切な場所に適切な硝材のレンズを使用することが必要となってくる。 In addition, by using a high refractive index glass material as the lens material, it becomes easy to correct spherical aberration well. However, it is difficult to correct axial chromatic aberration in the double gauss type, and in order to correct this, it is necessary to deform the lens configuration from the double gauss type and to use an appropriate glass lens in an appropriate place.
本発明では、開口絞りＳＰ近傍に接合レンズＬＲを配置し、接合レンズＬＲを正レンズＬＰＲと負レンズＬＲＮより構成し、このときの正レンズＬＲＰの材料と負レンズＬＲＮの材料を適切に設定することによって、色収差を良好に補正している。ダブルガウスタイプは大口径化する際に軸上光束が広がる開口絞りの物体側に高屈折率硝材のレンズを使用することで球面収差を良好に補正している。しかし、一般に高屈折率硝材は分散が大きいため、色収差を良好に補正しつつ、球面収差、像面湾曲などの諸収差を良好に補正するが難しくなる。 In the present invention, the cemented lens LR is disposed near the aperture stop SP, the cemented lens LR is configured of the positive lens LPR and the negative lens LRN, and the material of the positive lens LRP and the material of the negative lens LRN at this time are appropriately set. By this, the chromatic aberration is corrected well. In the double Gaussian type, the spherical aberration is well corrected by using a lens of a high refractive index glass material on the object side of the aperture stop where the axial light beam spreads when increasing the aperture. However, generally, a high refractive index glass material has a large dispersion, so it is difficult to satisfactorily correct various aberrations such as spherical aberration and curvature of field while properly correcting chromatic aberration.
本発明ではこれらの収差を良好に補正するために比較的軸上光束が大きい開口絞りＳＰ近傍に接合レンズＬＲを配置し、正レンズＬＲＰの材料に部分分散比が大きい硝材、負レンズＬＲＮの材料に部分分散比が小さい硝材を使用している。これにより２次の色消しを考慮した色収差の補正を効果的に行っている。開口絞りよりも物体側のレンズ群に高屈折率硝材のレンズを使用し、開口絞りＳＰ近傍に接合レンズを配置すると、全系の小型化を図りつつ軸上色収差の補正が容易になるが、開口絞りＳＰ近傍でコマ収差が発生し、コマ収差の補正が難しくなる。 In the present invention, in order to correct these aberrations well, the cemented lens LR is disposed near the aperture stop SP having a relatively large axial luminous flux, and the material of the positive lens LRP is a glass material having a large partial dispersion ratio, and the material of the negative lens LRN. Use a glass material with a low partial dispersion ratio. Thereby, the correction of the chromatic aberration in consideration of the secondary achromatism is effectively performed. If a lens with a high refractive index glass material is used for the lens unit on the object side of the aperture stop and a cemented lens is placed near the aperture stop SP, correction of on-axis chromatic aberration is facilitated while achieving downsizing of the entire system. A coma aberration occurs near the aperture stop SP, making it difficult to correct the coma aberration.
そこで本発明では、開口絞りＳＰ近傍に配置した負レンズＬＲＮと、正レンズＬＲＰに使用する硝材の範囲を適切に設定することで色収差とコマ収差を良好に補正している。これらの構成を採用することで全系が小型でかつ大口径化で高画質の像を得ている。 Therefore, in the present invention, the chromatic aberration and the coma are well corrected by appropriately setting the range of the glass material used for the negative lens LRN and the positive lens LRP arranged in the vicinity of the aperture stop SP. By adopting these configurations, a high-quality image is obtained with the entire system being compact and having a large aperture.
本発明の撮像光学系Ｌ０において、負レンズＬＲＮと正レンズＬＲＰの材料のアッベ数を各々νｄｎＲ、νｄｐＲとする。負レンズＬＲＮと正レンズＬＲＰの材料の部分分散比を各々θｇＦｎＲ、θｇＦｐＲとする。 In the imaging optical system L0 of the present invention, Abbe numbers of materials of the negative lens LRN and the positive lens LRP are respectively νdnR and dpdpR. The partial dispersion ratios of the materials of the negative lens LRN and the positive lens LRP are θgFnR and θgFpR, respectively.
このとき、
θｇＦｎＲ−（−０．００２４０νｄｎＲ＋０．６６９４）＜０．０ ・・・（１）
３０．０＜νｄｎＲ ・・・（１ｘ）
０．０＜θｇＦｐＲ−（−０．０００８３νｄｐＲ＋０．５９８１） ・・・（２）
４２．０＜νｄｐＲ＜８０．０ ・・・（２ｘ）
なる条件式を満足する。但し条件式（１）は条件式（１ｘ）を満足することを前提とし、条件式（２）は条件式（２ｘ）を満足することを前提としている。
At this time,
θ g F n R − (−0.00 240 dn d n R + 0.6 694) <0.0 (1)
30.0 <νdnR (1x)
0.0 <θgFpR − (− 0.00083νdpR + 0.5981) (2)
42.0 <νdpR <80.0 ・ ・ ・ (2x)
Satisfy the following conditional expression. However, conditional expression (1) presupposes that conditional expression (1x) is satisfied, and conditional expression (2) presupposes that conditional expression (2x) is satisfied.
次に前述の各条件式の技術的意味について説明する。本発明の撮像光学系Ｌ０では比較的軸上光束が大きい開口絞りＳＰ近傍に正レンズＬＲＰと負レンズＬＲＮを接合した接合レンズを配置している。そして正レンズＬＲＰに部分分散比が大きい硝材、負レンズＬＲＮに部分分散比が小さい硝材を使用することで色収差を効果的に補正している。 Next, technical meanings of the above-mentioned conditional expressions will be described. In the imaging optical system L0 of the present invention, a cemented lens in which a positive lens LRP and a negative lens LRN are cemented is disposed in the vicinity of the aperture stop SP having a relatively large axial luminous flux. The chromatic aberration is effectively corrected by using a glass material having a large partial dispersion ratio for the positive lens LRP and a glass material having a small partial dispersion ratio for the negative lens LRN.
条件式（１）は、開口絞りＳＰに隣接して像側に配置された接合レンズＬＲに含まれる負レンズＬＲＮの硝材に関し、主に特に軸上色収差を良好に補正するためのものである。条件式（１）の上限値を上回ると、２次の色消し効果が小さくなり、特に軸上色収差を良好に補正するのが困難となる。また、負レンズＬＲＮが低分散となり、１次の色消し効果も小さくなるため、色収差の補正が困難になる。 The conditional expression (1) relates mainly to a glass material of the negative lens LRN included in the cemented lens LR disposed on the image side adjacent to the aperture stop SP, and in particular, for favorably correcting axial chromatic aberration. If the upper limit value of the conditional expression (1) is exceeded, the secondary achromatic effect becomes small, and in particular, it becomes difficult to satisfactorily correct axial chromatic aberration. In addition, since the negative lens LRN has low dispersion and the primary achromatic effect is also reduced, it is difficult to correct the chromatic aberration.
条件式（２）は、開口絞りＳＰに隣接して像側に配置された接合レンズＬＲに含まれる正レンズＬＲＰの硝材に関し、主に軸上色収差を良好に補正するためのものである。条件式（２）の下限値を下回ると、２次の色消し効果が小さくなり、特に軸上色収差を良好に補正するのが困難となる。 The conditional expression (2) mainly relates to the satisfactory correction of the axial chromatic aberration for the glass material of the positive lens LRP included in the cemented lens LR disposed on the image side adjacent to the aperture stop SP. When the lower limit value of the conditional expression (2) is not reached, the secondary achromatic effect becomes small, and it becomes difficult to correct particularly the axial chromatic aberration well.
尚、各実施例において、収差補正上更に好ましくは、条件式（１）、（２）の数値範囲を次の如く設定するのが良い。
−０．０２＜θｇＦｎＲ−（−０．００２４０νｄｎＲ＋０．６６９４）＜０．０
・・・（１ａ）
０．０＜θｇＦｐＲ−（−０．０００８３νｄｐＲ＋０．５９８１）＜０．０２
・・・（２ａ）
In each embodiment, in view of aberration correction, it is more preferable to set the numerical ranges of the conditional expressions (1) and (2) as follows.
−0.02 <θgFnR − (− 0.00240νdnR + 0.6694) <0.0
... (1a)
0.0 <θgFpR − (− 0.00083νdpR + 0.5981) <0.02
... (2a)
より更に好ましくは、条件式（１ａ）、（２ａ）の数値範囲を次の如く設定するのが良い。
−０．０１＜θｇＦｎＲ−（−０．００２４０νｄｎＲ＋０．６６９４）＜０．０
・・・（１ｂ）
０．０＜θｇＦｐＲ−（−０．０００８３νｄｐＲ＋０．５９８１）＜０．０１
・・・（２ｂ）
Still more preferably, the numerical range of the conditional expressions (1a) and (2a) may be set as follows.
−0.01 <θgFnR − (− 0.00240 vdn R + 0.6694) <0.0
... (1b)
0.0 <θgFpR − (− 0.00083νdpR + 0.5981) <0.01
... (2b)
以上のように本発明によれば、Ｆナンバー１．４程度の大口径でありながら色収差を低減し高画質かつ小型でボケ味のきれいな撮像光学系が得られる。 As described above, according to the present invention, it is possible to obtain an image pickup optical system which has a large aperture of about F number 1.4, reduces chromatic aberration, has high image quality, is compact, and has a beautiful blur.
本発明において更に好ましくは次の条件式のうち１つ以上を満足するのが良い。負レンズＬＲＮの材料の屈折率をＮｄｎＲ、正レンズＬＲＰの材料の屈折率をＮｄｐＲとする。接合レンズＬＲの焦点距離をｆＲ、全系の焦点距離をｆとする。前群は１枚以上の正レンズを有し、このうち少なくとも１枚の正レンズは材料の屈折率をＮｄＦＰとする。前群は開口絞りＳＰに隣接して配置された接合レンズＬＦを有し、接合レンズＬＦは負レンズＬＦＮと正レンズＬＦＰが接合されて構成されている。 In the present invention, it is more preferable to satisfy one or more of the following conditional expressions. The refractive index of the material of the negative lens LRN is NdnR, and the refractive index of the material of the positive lens LRP is NdpR. The focal length of the cemented lens LR is fR, and the focal length of the entire system is f. The front group has one or more positive lenses, of which at least one positive lens has a refractive index of NdFP as the material. The front group has a cemented lens LF disposed adjacent to the aperture stop SP, and the cemented lens LF is configured by cementing a negative lens LFN and a positive lens LFP.
負レンズＬＦＮと正レンズＬＦＰの材料のアッベ数を各々νｄｎＦ、νｄｐＦとする。負レンズＬＦＮと正レンズＬＦＰの材料の部分分散比を各々θｇＦｎＦ、θｇＦｐＦとする。負レンズＬＦＮの材料の屈折率をＮｄｎＦ、正レンズＬＦＰの材料の屈折率をＮｄｐＦとする。 The Abbe numbers of the materials of the negative lens LFN and the positive lens LFP are denoted by dndnF and νdpF, respectively. The partial dispersion ratios of the materials of the negative lens LFN and the positive lens LFP are respectively θgFnF and θgFpF. The refractive index of the material of the negative lens LFN is NdnF, and the refractive index of the material of the positive lens LFP is NdpF.
このとき次の条件式のうち１つ以上を満足するのが良い。
ＮｄｎＲ−ＮｄｐＲ＜−０．０５ ・・・（３）
−３０．０＜νｄｎＲ−νｄｐＲ＜−５．０ ・・・（４）
−０．９５＜ｆＲ／ｆ＜−０．７０ ・・・（５）
１．９０＜ＮｄＦＰ ・・・（６）
θｇＦｎＦ−（−０．００２４０νｄｎＦ＋０．６６９４）＜０．０ ・・・（７）
３０．０＜νｄｎＦ ・・・（７ｘ）
０．０＜θｇＦｐＦ−（−０．０００８３νｄｐＦ＋０．５９８１） ・・・（８）
４２．０＜νｄｐＦ＜８０．０ ・・・（８ｘ）
０．０５＜ＮｄｎＦ−ＮｄｐＦ ・・・（９）
At this time, it is preferable to satisfy one or more of the following conditional expressions.
NdnR-NdpR <-0.05 (3)
-30.0 <νdnR-νdpR <-5.0 (4)
−0.95 <fR / f <−0.70 (5)
1.90 <NdFP (6)
θ g F n F − (−0.00 240 dn d n F + 0.6 694) <0.0 (7)
30.0 <νdnF (7x)
0.0 <θgFpF − (− 0.00083νdpF + 0.5981) (8)
42.0 <νdpF <80.0 ・ ・ ・ (8x)
0.05 <NdnF-NdpF (9)
但し条件式（７）は条件式（７ｘ）を満足することが前提となる。条件式（８）は条件式（８ｘ）を満足することが前提となる。 However, conditional expression (7) assumes that conditional expression (7x) is satisfied. Conditional expression (8) is premised to satisfy conditional expression (8x).
次に前述の各条件式の技術的意味について説明する。条件式（３）は、開口絞りＳＰに隣接して像側に配置された接合レンズＬＲに含まれる正レンズＬＲＰの材料と負レンズＬＲＮの材料の屈折率差に関し、主に像面湾曲、コマ収差を良好に補正するためのものである。条件式（３）の上限値を上回ると、球面収差の補正とコマ収差の補正は容易となるが、ペッツバール和が増大し、像面湾曲を良好に補正するのが困難になる。 Next, technical meanings of the above-mentioned conditional expressions will be described. Condition (3) mainly relates to the curvature of field and coma regarding the difference in refractive index between the material of the positive lens LRP and the material of the negative lens LRN included in the cemented lens LR disposed on the image side adjacent to the aperture stop SP. It is intended to correct the aberration well. If the upper limit value of the conditional expression (3) is exceeded, correction of spherical aberration and correction of coma aberration become easy, but Petzval sum increases and it becomes difficult to correct curvature of field well.
条件式（４）は、開口絞りＳＰに隣接して像側に配置された接合レンズＬＲに含まれる正レンズＬＲＰの材料と負レンズＬＲＮの材料のアッベ数の差に関し、主に軸上色収差とコマ収差を良好に補正するためのものである。条件式（４）の下限値を下回ると、アッベ数の差が小さくなり、１次の色消しを行う上で困難となる。また、各々のレンズの屈折力が強まり、レンズ径が大型化してくるため好ましくない。一方、条件式（４）の上限値を上回ると、アッベ数の差が大きくなり、各々のレンズの屈折力が弱まるためレンズ径の小型化、色収差の補正は容易になるが、コマ収差を良好に補正するのが困難となる。 Condition (4) mainly relates to axial chromatic aberration and the difference in Abbe number between the material of the positive lens LRP and the material of the negative lens LRN included in the cemented lens LR disposed on the image side adjacent to the aperture stop SP. It is intended to correct coma aberration well. When the value goes below the lower limit value of the conditional expression (4), the difference in Abbe's numbers becomes small, which makes it difficult to perform primary achromatization. In addition, the refractive power of each lens is intensified, and the diameter of the lens is undesirably increased. On the other hand, beyond the upper limit value of the conditional expression (4), the difference in Abbe number becomes large and the refractive power of each lens becomes weak, so the lens diameter can be made smaller and the correction of the chromatic aberration becomes easy. It is difficult to make corrections.
条件式（５）は、開口絞りＳＰに隣接して像側に配置された接合レンズＬＲの屈折力に関し、球面収差、像面湾曲を良好に補正するためのものである。条件式（５）の下限値を下回ると、負の屈折力が弱まるので球面収差、コマ収差の補正は容易となるが、ペッツバール和がプラス方向に大きくなるため像面湾曲を良好に補正するのが困難となる。一方、条件式（５）の上限値を上回ると、負の屈折力が強まるのでペッツバール和が補正されるため像面湾曲の補正は容易となるが、球面収差、コマ収差を良好に補正するのが困難となる。 The conditional expression (5) is for properly correcting the spherical aberration and the curvature of field with respect to the refractive power of the cemented lens LR disposed on the image side adjacent to the aperture stop SP. Below the lower limit of conditional expression (5), negative refractive power weakens, so correction of spherical aberration and coma aberration becomes easy, but Petzval's sum increases in the positive direction, and field curvature is corrected well. Is difficult. On the other hand, if the upper limit value of the conditional expression (5) is exceeded, the negative refracting power is enhanced and the Petzval sum is corrected, so the correction of the field curvature becomes easy, but the spherical aberration and the coma are corrected well. Is difficult.
条件式（６）は、開口絞りＳＰより物体側に配置された１枚以上の正レンズのうちの少なくとも１つの正レンズの材料の屈折率に関し、主に球面収差、像面湾曲を良好に補正するためのものである。条件式（６）の下限値を下回ると、ペッツバール和がプラス方向に大きくなるため像面湾曲を補正するのが困難となる。また、球面収差を補正するためにレンズ面の曲率が強まり、レンズが大型化するため好ましくない。 Condition (6) mainly corrects spherical aberration and field curvature favorably with respect to the refractive index of the material of at least one positive lens of one or more positive lenses disposed on the object side of the aperture stop SP. It is to do. Below the lower limit value of the conditional expression (6), the Petzval sum becomes larger in the positive direction, and it becomes difficult to correct the field curvature. In addition, the curvature of the lens surface is intensified to correct the spherical aberration, and the lens becomes large.
条件式（７）は、開口絞りＳＰに隣接して物体側に配置された接合レンズＬＦに含まれる負レンズＬＦＮの材料に関し、主に軸上色収差を良好に補正するためのものである。条件式（７）の上限値を上回ると、２次の色消し効果が小さくなり、特に軸上色収差を補正するのが困難となる。また、負レンズＬＦＮの材料が低分散となり、１次の色消し効果も小さくなるため、色収差の補正が困難になる。 The conditional expression (7) mainly relates to favorably correcting the axial chromatic aberration with respect to the material of the negative lens LFN included in the cemented lens LF disposed on the object side adjacent to the aperture stop SP. When the value exceeds the upper limit value of the conditional expression (7), the secondary achromatic effect becomes small, and in particular, it becomes difficult to correct axial chromatic aberration. In addition, since the material of the negative lens LFN is low-dispersion and the first-order achromatizing effect is also small, it is difficult to correct the chromatic aberration.
条件式（８）は、開口絞りＳＰに隣接して物体側に配置された接合レンズＬＦに含まれる正レンズＬＦＰの材料に関し、主に軸上色収差を良好に補正するためのものである。条件式（８）の下限値を下回ると、２次の色消し効果が小さくなり、軸上色収差を良好に補正するのが困難となる。 The conditional expression (8) mainly relates to good correction of axial chromatic aberration with respect to the material of the positive lens LFP included in the cemented lens LF disposed on the object side adjacent to the aperture stop SP. When the lower limit value of the conditional expression (8) is not reached, the secondary achromatic effect becomes small, and it becomes difficult to correct the axial chromatic aberration well.
条件式（９）は、開口絞りＳＰに隣接して物体側に配置された接合レンズＬＦに含まれる正レンズＬＦＰの材料と負レンズＬＦＮの材料の屈折率差に関し、主に球面収差、コマ収差を良好に補正するためのものである。条件式（９）の下限値を下回ると、ペッツバール和を補正するのが容易となるが、球面収差と、コマ収差を良好に補正するのが困難となる。 The conditional expression (9) relates mainly to spherical aberration and coma regarding the difference in refractive index between the material of the positive lens LFP and the material of the negative lens LFN included in the cemented lens LF disposed on the object side adjacent to the aperture stop SP. To make a good correction. If the lower limit value of the conditional expression (9) is not reached, it becomes easy to correct the Petzval sum, but it becomes difficult to correct the spherical aberration and the coma properly.
尚、各実施例において、収差補正上更に好ましくは、条件式（３）乃至（９）の数値範囲を次の如く設定するのが良い。
−０．３０＜ＮｄｎＲ−ＮｄｐＲ＜−０．０５ ・・・（３ａ）
−２５．０＜νｄｎＲ−νｄｐＲ＜−５．０ ・・・（４ａ）
−０．９３＜ｆＲ／ｆ＜−０．７２ ・・・（５ａ）
１．９０＜ＮｄＦＰ＜２．５０ ・・・（６ａ）
−０．０２＜θｇＦｎＦ−（−０．００２４０νｄｎＦ＋０．６６９４）＜０．００
・・・（７ａ）
０．００＜θｇＦｐＦ−（−０．０００８３νｄｐＦ＋０．５９８１）＜０．０２
・・・（８ａ）
０．０５＜ＮｄｎＦ−ＮｄｐＦ＜０．３０ ・・・（９ａ）
In each embodiment, it is more preferable to set the numerical ranges of the conditional expressions (3) to (9) as follows in view of aberration correction.
-0.30 <NdnR-NdpR <-0.05 (3a)
−25.0 <νdnR−νdpR <−5.0 (4a)
−0.93 <fR / f <−0.72 (5a)
1.90 <NdFP <2.50 (6a)
−0.02 <θgFnF − (− 0.00240νdnF + 0.6694) <0.00
... (7a)
0.00 <θgFpF − (− 0.00083νdpF + 0.5981) <0.02
... (8a)
0.05 <NdnF−Nd pF <0.30 (9a)
より更に好ましくは、条件式（３ａ）乃至（９ａ）の数値範囲を次の如く設定するのが良い。
−０．２０＜ＮｄｎＲ−ＮｄｐＲ＜−０．０５ ・・・（３ｂ）
−２０．０＜νｄｎＲ−νｄｐＲ＜−７．０ ・・・（４ｂ）
−０．９０＜ｆＲ／ｆ＜−０．７５ ・・・（５ｂ）
１．９０＜ＮｄＦＰ＜２．３０ ・・・（６ｂ）
−０．０１＜θｇＦｎＦ−（−０．００２４０νｄｎＦ＋０．６６９４）＜０．００
・・・（７ｂ）
０．００＜θｇＦｐＦ−（−０．０００８３νｄｐＦ＋０．５９８１）＜０．０１
・・・（８ｂ）
０．０５＜ＮｄｎＦ−ＮｄｐＦ＜０．２０ ・・・（９ｂ）
Still more preferably, the numerical ranges of the conditional expressions (3a) to (9a) may be set as follows.
−0.20 <NdnR−NdpR <−0.05 (3b)
−20.0 <νdnR−νdpR <−7.0 (4b)
−0.90 <fR / f <−0.75 (5b)
1.90 <NdFP <2.30 (6b)
−0.01 <θgFnF − (− 0.00240νdnF + 0.6694) <0.00
... (7b)
0.00 <θgFpF − (− 0.00083νdpF + 0.5981) <0.01
... (8b)
0.05 <NdnF−Nd pF <0.20 (9 b)
各実施例では以上のように各レンズ群を構成することによって、Ｆナンバー１．４程度の大口径でありながら色収差を低減し高画質かつ小型でボケ味のきれいな撮像光学系を得ている。 In each embodiment, by configuring each lens group as described above, the chromatic aberration is reduced while having a large aperture of about F number 1.4, and an image pickup optical system which is high in image quality and small in size and has a beautiful blur is obtained.
次に実施例１、３、４、６の各レンズ群のレンズ構成について説明する。第１レンズ群Ｌ１は物体側のレンズ面が凹形状の負レンズ、正レンズと負レンズを接合した接合レンズ、正レンズ、正レンズＬＦＰと負レンズＬＦＮを接合した接合レンズＬＦを有する。更に開口絞りＳＰ、正レンズＬＲＰと負レンズＬＲＮを接合した接合レンズＬＲ、正レンズと負レンズを接合した接合レンズ、負レンズと正レンズを接合した接合レンズより構成している。ここで負レンズＬＦＮは正レンズＬＦＰの像側に隣接して配置されている。 Next, the lens configuration of each lens unit of Embodiments 1, 3, 4, and 6 will be described. The first lens unit L1 has a negative lens with a concave lens surface on the object side, a cemented lens in which a positive lens and a negative lens are cemented, a cemented lens LF in which a positive lens and a positive lens LFP and a negative lens LFN are cemented. Furthermore, it comprises an aperture stop SP, a cemented lens LR in which a positive lens LRP and a negative lens LRN are cemented, a cemented lens in which a positive lens and a negative lens are cemented, and a cemented lens in which a negative lens and a positive lens are cemented. Here, the negative lens LFN is disposed adjacent to the image side of the positive lens LFP.
各実施例の撮像光学系では全系を小型とするために第１レンズ群Ｌ１の屈折力を適切な範囲で強めている。このとき、第１レンズ群Ｌ１内で諸収差、特にサジタルフレア、像面湾曲が多く発生してくる。 In the imaging optical system of each embodiment, the refractive power of the first lens unit L1 is increased in an appropriate range in order to make the entire system compact. At this time, various aberrations, in particular, sagittal flare and curvature of field occur in the first lens unit L1.
そこで最も物体側に凹面を向けた負レンズを配置することで、第１レンズ群Ｌ１で発生するサジタルフレアを抑制している。また、正レンズに高屈折率の硝材を使用する事で像面湾曲の発生、接合レンズを複数配置する事で軸上色収差、倍率色収差の発生を軽減している。特に開口絞りＳＰ付近に配置した接合レンズには高部分分散材と低部分分散材を効果的に配置し、色収差を軽減している。 Therefore, the sagittal flare generated in the first lens unit L1 is suppressed by arranging a negative lens having a concave surface facing the most object side. Further, the use of a glass material with a high refractive index for the positive lens reduces the occurrence of curvature of field and the arrangement of a plurality of cemented lenses reduces the occurrence of axial chromatic aberration and lateral chromatic aberration. In particular, the high partial dispersion material and the low partial dispersion material are effectively disposed on the cemented lens disposed in the vicinity of the aperture stop SP to reduce the chromatic aberration.
収差補正上、更に好ましくは、開口絞りＳＰ付近の接合レンズの材料のアッベ数は負レンズの材料のアッベ数νｄｎが、
３４．０＜νｄｎ＜５０．０
正レンズの材料のアッベ数νｄｐが、
４２．０＜νｄｐ＜７０．０
の如く設定するのが良い。第２レンズ群Ｌ２は両凸形状の正レンズと物体側が凹でメニスカス形状の負レンズを接合した接合レンズで構成している。
In aberration correction, more preferably, the Abbe number of the material of the cemented lens near the aperture stop SP is the Abbe number dndn of the material of the negative lens,
34.0 <νdn <50.0
The Abbe number dpdp of the material of the positive lens is
42.0 <νdp <70.0
It is good to set like. The second lens unit L2 is composed of a double convex positive lens and a cemented lens in which an object side is concave and a meniscus negative lens is cemented.
各実施例の撮像光学系ではフォーカシングによる光学性能の変化を抑制、撮像素子への光線入射角を抑制するために第２レンズ群Ｌ２の屈折力を適切な範囲で強めている。各実施例では、接合レンズとすることによりフォーカス全域で色収差を軽減している。また、高屈折率の硝材を使用する事でペッツバール和の抑制、フォーカシングによるコマ収差の変動を軽減している。 In the imaging optical system of each embodiment, the refractive power of the second lens unit L2 is strengthened in an appropriate range in order to suppress the change in optical performance due to focusing and to suppress the light incident angle to the imaging device. In each of the embodiments, the cemented lens reduces chromatic aberration over the entire focus range. In addition, the use of a glass material with a high refractive index suppresses the Petzval sum and reduces the fluctuation of coma due to focusing.
尚、収差補正上、必要に応じて接合レンズは空気レンズを介した２枚のレンズ構成としても良い。フォーカシングは第１レンズ群Ｌ１によって行っている。 Incidentally, in order to correct aberration, the cemented lens may be configured as a two-lens structure via an air lens as necessary. Focusing is performed by the first lens unit L1.
次に実施例２の各レンズ群のレンズ構成について説明する。第１レンズ群Ｌ１は物体側のレンズ面が凹形状の負レンズ、正レンズと負レンズを接合した接合レンズ、正レンズ、正レンズＬＦＰと負レンズＬＦＮを接合した接合レンズＬＦを有する。更に開口絞りＳＰ、負レンズＬＲＮと正レンズＬＲＰを接合した接合レンズＬＲ、正レンズと負レンズを接合した接合レンズ、負レンズ、正レンズより構成している。ここで負レンズＬＦＮは正レンズＬＦＰの像側に隣接して配置されている。 Next, the lens configuration of each lens unit of Embodiment 2 will be described. The first lens unit L1 has a negative lens with a concave lens surface on the object side, a cemented lens in which a positive lens and a negative lens are cemented, a cemented lens LF in which a positive lens and a positive lens LFP and a negative lens LFN are cemented. Furthermore, it comprises an aperture stop SP, a cemented lens LR in which a negative lens LRN and a positive lens LRP are cemented, a cemented lens in which a positive lens and a negative lens are cemented, a negative lens and a positive lens. Here, the negative lens LFN is disposed adjacent to the image side of the positive lens LFP.
実施例２の撮像光学系では全系を小型とするために第１レンズ群Ｌ１の屈折力を適切な範囲で強めている。このとき、第１レンズ群Ｌ１内で諸収差、特にサジタルフレア、像面湾曲が多く発生してくる。 In the imaging optical system of Embodiment 2, the refractive power of the first lens unit L1 is increased in an appropriate range in order to make the entire system compact. At this time, various aberrations, in particular, sagittal flare and curvature of field occur in the first lens unit L1.
そこで最も物体側に凹面を向けた負レンズを配置することで、第１レンズ群Ｌ１で発生するサジタルフレアを抑制している。また、正レンズに高屈折率の硝材を使用する事で像面湾曲の発生、接合レンズを複数配置する事で軸上色収差、倍率色収差の発生を軽減している。特に開口絞りＳＰ付近に配置した接合レンズには高部分分散材と低部分分散材を効果的に配置し、色収差を軽減している。 Therefore, the sagittal flare generated in the first lens unit L1 is suppressed by arranging a negative lens having a concave surface facing the most object side. Further, the use of a glass material with a high refractive index for the positive lens reduces the occurrence of curvature of field and the arrangement of a plurality of cemented lenses reduces the occurrence of axial chromatic aberration and lateral chromatic aberration. In particular, the high partial dispersion material and the low partial dispersion material are effectively disposed on the cemented lens disposed in the vicinity of the aperture stop SP to reduce the chromatic aberration.
収差補正上、更に好ましくは、開口絞りＳＰ付近の接合レンズの材料のアッベ数は負レンズの材料のアッベ数νｄｎが、
３４．０＜νｄｎ＜５０．０
正レンズの材料のアッベ数νｄｐが、
４２．０＜νｄｐ＜７０．０
の如く設定するのが良い。
In aberration correction, more preferably, the Abbe number of the material of the cemented lens near the aperture stop SP is the Abbe number dndn of the material of the negative lens,
34.0 <νdn <50.0
The Abbe number dpdp of the material of the positive lens is
42.0 <νdp <70.0
It is good to set like.
第２レンズ群Ｌ２は両凸形状の正レンズと物体側が凹でメニスカス形状の負レンズを接合した接合レンズで構成している。実施例２の撮像光学系ではフォーカシングによる光学性能の変化を抑制、撮像素子への光線入射角を抑制するために第２レンズ群Ｌ２の屈折力を適切な範囲で強めている。実施例２では、接合レンズとすることによりフォーカス全域で色収差を軽減している。また、高屈折率の硝材を使用する事でペッツバール和の抑制、フォーカシングによるコマ収差の変動を軽減している。 The second lens unit L2 is composed of a double convex positive lens and a cemented lens in which an object side is concave and a meniscus negative lens is cemented. In the imaging optical system of Example 2, the refractive power of the second lens unit L2 is strengthened in an appropriate range in order to suppress a change in optical performance due to focusing and to suppress an incident angle of light to the imaging device. In the second embodiment, chromatic aberration is reduced over the entire focus range by using a cemented lens. In addition, the use of a glass material with a high refractive index suppresses the Petzval sum and reduces the fluctuation of coma due to focusing.
尚、収差補正上、必要に応じて接合レンズは空気レンズを介した２枚のレンズ構成としても良い。フォーカシングは第１レンズ群Ｌ１によって行っている。 Incidentally, in order to correct aberration, the cemented lens may be configured as a two-lens structure via an air lens as necessary. Focusing is performed by the first lens unit L1.
次に実施例５の各レンズ群のレンズ構成について説明する。第１レンズ群Ｌ１は物体側のレンズ面が凹形状の負レンズ、正レンズと負レンズを接合した接合レンズ、正レンズ、正レンズＬＦＰと負レンズＬＦＮを接合した接合レンズＬＦ、開口絞りＳＰを有する。更に正レンズＬＲＰと負レンズＬＲＮを接合した接合レンズＬＲ、正レンズと負レンズを接合した接合レンズ、負レンズと正レンズを接合した接合レンズ、両凸形状の正レンズと物体側が凹でメニスカス形状の負レンズを接合した接合レンズより構成している。ここで負レンズＬＦＮは正レンズＬＦＰの像側に隣接して配置されている。 Next, the lens configuration of each lens unit of the fifth embodiment will be described. The first lens unit L1 includes a negative lens with a concave lens surface on the object side, a cemented lens in which a positive lens and a negative lens are cemented, a positive lens, a cemented lens LF in which a positive lens LFP and a negative lens LFN are cemented, and an aperture stop SP. Have. Further, a cemented lens LR in which a positive lens LRP and a negative lens LRN are cemented, a cemented lens in which a positive lens and a negative lens are cemented, a cemented lens in which a negative lens and a positive lens are cemented, and a biconvex positive lens and an object side concave with a meniscus shape It is comprised from the cemented lens which cemented the negative lens of. Here, the negative lens LFN is disposed adjacent to the image side of the positive lens LFP.
実施例５の撮像光学系では全系を小型とするために第１レンズ群Ｌ１の屈折力を適切な範囲で強めている。このとき、第１レンズ群Ｌ１内で諸収差、特にサジタルフレア、像面湾曲が多く発生してくる。 In the imaging optical system of Embodiment 5, the refractive power of the first lens unit L1 is increased in an appropriate range in order to make the entire system compact. At this time, various aberrations, in particular, sagittal flare and curvature of field occur in the first lens unit L1.
そこで最も物体側に凹面を向けた負レンズを配置することで、第１レンズ群Ｌ１で発生するサジタルフレアを抑制している。また、正レンズに高屈折率の硝材を使用する事で像面湾曲の発生、接合レンズを複数配置する事で軸上色収差、倍率色収差の発生を軽減している。特に開口絞りＳＰ付近に配置した接合レンズには高部分分散材と低部分分散材を効果的に配置し、色収差を軽減している。 Therefore, the sagittal flare generated in the first lens unit L1 is suppressed by arranging a negative lens having a concave surface facing the most object side. Further, the use of a glass material with a high refractive index for the positive lens reduces the occurrence of curvature of field and the arrangement of a plurality of cemented lenses reduces the occurrence of axial chromatic aberration and lateral chromatic aberration. In particular, the high partial dispersion material and the low partial dispersion material are effectively disposed on the cemented lens disposed in the vicinity of the aperture stop SP to reduce the chromatic aberration.
収差補正上、更に好ましくは、開口絞りＳＰ付近の接合レンズの材料のアッベ数は負レンズの材料のアッベ数νｄｎが、
３４．０＜νｄｎ＜５０．０
正レンズの材料のアッベ数νｄｐが、
４２．０＜νｄｐ＜７０．０
の如く設定するのが良い。
In aberration correction, more preferably, the Abbe number of the material of the cemented lens near the aperture stop SP is the Abbe number dndn of the material of the negative lens,
34.0 <νdn <50.0
The Abbe number dpdp of the material of the positive lens is
42.0 <νdp <70.0
It is good to set like.
実施例５では、接合レンズとすることによりフォーカス全域で色収差を軽減している。また、高屈折率の硝材を使用する事でペッツバール和の抑制、フォーカシングによるコマ収差の変動を軽減している。尚、収差補正上、必要に応じて接合レンズは空気レンズを介した２枚のレンズ構成としても良い。フォーカシングは第１レンズ群Ｌ１によって行っている。 In the fifth embodiment, chromatic aberration is reduced over the entire focus range by using a cemented lens. In addition, the use of a glass material with a high refractive index suppresses the Petzval sum and reduces the fluctuation of coma due to focusing. Incidentally, in order to correct aberration, the cemented lens may be configured as a two-lens structure via an air lens as necessary. Focusing is performed by the first lens unit L1.
実施例１乃至４、６では、無限遠から至近距離へのフォーカシングに際して矢印のように、第１レンズ群Ｌ１を物体側に移動することによって行う。フォーカシングに際して第２レンズ群Ｌ２は不動だが、収差補正上移動させても良い。実施例５では、無限遠から至近距離へのフォーカスに際して矢印のように、第１レンズ群Ｌ１（レンズ全体）を物体側に移動することによって行う。 In the first to fourth and sixth embodiments, focusing from infinity to a close distance is performed by moving the first lens unit L1 to the object side as indicated by an arrow. During focusing, the second lens unit L2 does not move but may be moved for aberration correction. In the fifth embodiment, when focusing from infinity to a close distance, the first lens unit L1 (entire lens) is moved to the object side as indicated by an arrow.
次に本発明の撮像光学系を用いた撮像装置（デジタルカメラ）の実施例を図１３を用いて説明する。図１３において、３０はカメラ本体、３１は実施例１乃至６で説明したいずれかの撮像光学系である。撮像光学系３１によって形成された被写体像を受光するＣＣＤセンサやＣＭＯＳセンサ等の固体撮像素子（光電変換素子）はカメラ本体３０内に内蔵されている。 Next, an embodiment of an imaging apparatus (digital camera) using the imaging optical system of the present invention will be described with reference to FIG. In FIG. 13, reference numeral 30 denotes a camera body, and reference numeral 31 denotes any one of the imaging optical systems described in the first to sixth embodiments. A solid-state imaging device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor that receives an object image formed by the imaging optical system 31 is incorporated in the camera body 30.
以下、実施例１乃至６の具体的な数値データを示す。各数値データにおいてｉは物体側から数えた順序を示している。ｒｉは物体側からｉ番目の面の曲率半径、ｄｉは物体側からｉ番目の面とｉ＋１番目の面との間の面間隔、ｎｉは第ｉ番目のレンズのｄ線における屈折率、νｉは第ｉ番目のレンズのｄ線におけるアッベ数を示すものとする。非球面形状はｋを円錐定数、Ａ４、Ａ６、Ａ８、Ａ１０、Ａ１２を４次、６次、８次、１０次、１２次の非球面係数とし、光軸からの高さｈの位置での光軸方向の変位を面頂点を基準にしてｘとする。 Specific numerical data of Examples 1 to 6 will be shown below. In each numerical data, i indicates the order counted from the object side. ri is the radius of curvature of the ith surface from the object side, di is the surface distance between the ith surface and the (i + 1) th surface from the object side, ni is the refractive index at the d-line of the ith lens, νi is The Abbe number at the d-line of the i-th lens is shown. The aspheric surface shape is such that k is a conical constant, and A4, A6, A8, A10, and A12 are aspheric coefficients of fourth, sixth, eighth, tenth, and twelfth orders, at a height h from the optical axis. Let the displacement in the optical axis direction be x based on the surface vertex.
このとき、非球面形状は、
ｘ＝(ｈ2／Ｒ)／[１＋[１−(１＋Ｋ)(ｈ／Ｒ)2]1/2] ＋A4ｈ4＋A6ｈ6＋A8ｈ8＋A10ｈ10＋A12ｈ12
で表示される。但し、Ｒは近軸曲率半径である。「ｅ−Ｘ」は「×１０-X」を意味している。尚、非球面は各表中の面番号の右側に＊印を付している。また前述の各条件式と数値データとの関係を表１に示す。
At this time, the aspheric shape is
x = (h 2 / R) / [1+ [1- (1 + K) (h / R) 2] 1/2] + A4h 4 + A6h 6 + A8h 8 + A10h 10 + A12h 12
Is displayed. Where R is a paraxial radius of curvature. “E−X” means “× 10 −x ”. The aspheric surface is indicated by * on the right side of the surface number in each table. Also, the relationship between the above-mentioned conditional expressions and numerical data is shown in Table 1.
数値データ１
単位 mm
面データ
面番号 r d nd νd θgF
1 -34.245 1.10 1.61340 44.3
2 51.752 1.16
3 136.382 6.98 1.91082 35.3
4 -22.773 1.00 1.85478 24.8
5 -69.705 0.30
6 28.667 5.32 1.91082 35.3
7 -255.377 0.30
8 33.178 6.27 1.59282 68.6 0.5441
9 -48.343 1.00 1.73800 32.3 0.5899
10 20.267 4.11
11(絞り) ∞ 4.08
12 -19.197 2.30 1.76385 48.5 0.5589
13 -12.710 0.72 1.67542 34.8 0.5825
14 177.418 0.30
15 32.469 7.65 1.88300 40.8
16 -15.160 0.78 1.67270 32.1
17 -42.629 1.52
18 -20.007 0.82 1.51742 52.4
19 40.687 3.81 1.85135 40.1
20* -122.383 (可変)
21 99.228 5.55 1.88300 40.8
22 -27.877 0.92 2.00069 25.5
23 -138.637 8.52
24 ∞ 1.75 1.54400 60.0
25 ∞ 1.55
像面 ∞
Numerical data 1
Unit mm
Surface data surface number rd nd d d θgF
1 -34.245 1.10 1.61340 44.3
2 51.752 1.16
3 136.382 6.98 1.91082 35.3
4-22.773 1.00 1.85478 24.8
5-69. 705 0.30
6 28.667 5.32 1.91082 35.3
7-255.377 0.30
8 33.178 6.27 1.59282 68.6 0.5441
9 -48.343 1.00 1.73800 32.3 0.5899
10 20.267 4.11
11 (Aperture) 4.0 4.08
12 -19.197 2.30 1.76385 48.5 0.5589
13 -12.710 0.72 1.67542 34.8 0.5825
14 177.418 0.30
15 32.469 7.65 1.88300 40.8
16-15.160 0.78 1.67270 32.1
17-42.629 1.52
18-20.007 0.82 1.51742 52.4
19 40.687 3.81 1.85135 40.1
20 * -122.383 (variable)
21 99.228 5.55 1.88300 40.8
22-27.877 0.92 2.00069 25.5
23 -138.637 8.52
24 1. 1.75 1.54400 60.0
25 ∞ 1.55
Image plane ∞
非球面データ
第20面
K = 0.00000e+000 A 4= 2.81172e-005 A 6=-5.36397e-008 A 8= 1.08573e-009 A10=-7.33305e-012 A12= 1.98301e-014
各種データ
焦点距離 32.34
Fナンバー 1.45
半画角（度） 22.90
レンズ全長 68.28
BF 11.20
INF 至近
d20 1.10 9.71
レンズ群データ
群 始面 焦点距離 レンズ構成長
1 1 38.53 49.52
2 21 84.74 6.47
近距離撮像倍率：-0.188
Aspheric surface data plane 20
K = 0.00000e + 000A 4 = 2.81172e-005 A 6 = -5.36397e-008 A 8 = 1.08573e-009 A10 = -7.33305e-012 A12 = 1.98301e-014
Various data focal length 32.34
F number 1.45
Half angle of view (degrees) 22.90
Lens total length 68.28
BF 11.20
INF Close
d20 1.10 9.71
Lens group data group Start surface Focal length Lens configuration length
1 1 38.53 49.52
2 21 84.74 6.47
Near-field imaging magnification: -0.188
数値データ２
単位 mm
面データ
面番号 r d nd νd θgF
1 -36.349 1.05 1.61340 44.3
2 37.459 2.11
3 156.843 4.60 1.91082 35.3
4 -37.401 1.00 1.85478 24.8
5 -111.264 0.15
6 40.893 5.82 1.76385 48.5
7 -56.897 0.15
8 18.350 6.97 1.69700 48.5 0.5589
9 562.934 0.90 1.74951 35.3 0.5818
10 14.199 5.74
11(絞り) ∞ 3.18
12 -26.246 0.60 1.67300 38.2 0.5754
13 13.144 3.25 1.76385 48.5 0.5589
14 47.624 0.15
15 25.764 6.25 1.88300 40.8
16 -17.437 0.70 1.58144 40.8
17 258.711 3.12
18 -17.043 0.75 1.71736 29.5
19 -46.972 0.30
20 83.904 2.97 1.85135 40.1
21* -57.697 (可変)
22 74.180 3.92 1.80400 46.6
23 -46.887 0.90 2.00069 25.5
24 -184.643 8.52
25 ∞ 1.75 1.54400 60.0
26 ∞ 1.55
像面 ∞
Numerical data 2
Unit mm
Surface data surface number rd nd d d θgF
1 -36.349 1.05 1.61340 44.3
2 37.459 2.11
3 156.843 4.60 1.91082 35.3
4-37.401 1.00 1.85478 24.8
5-111.264 0.15
6 40.893 5.82 1.76385 48.5
7-56. 897 0.15
8 18.350 6.97 1.69700 48.5 0.5589
9 562.934 0.90 1.74951 35.3 0.5818
10 14.199 5.74
11 (aperture) ∞ 3.18
12 -26.246 0.60 1.67300 38.2 0.5754
13 13.144 3.25 1.76385 48.5 0.5589
14 47.624 0.15
15 25.764 6.25 1.88300 40.8
16-17.437 0.70 1.58184 40.8
17 258.711 3.12
18-17.043 0.75 1.71736 29.5
19-46. 972 0.30
20 83.904 2.97 1.85135 40.1
21 *-57. 697 (variable)
22 74.180 3.92 1.80400 46.6
23-46.887 0.90 2.00069 25.5
24 -184.643 8.52
25 1. 1.75 1.54400 60.0
26 1.5 1.55
Image plane ∞
非球面データ
第21面
K = 0.00000e+000 A 4= 3.46800e-005 A 6=-4.45749e-008 A 8= 9.40073e-010 A10=-3.72875e-012 A12= 8.03246e-015
各種データ
広角
焦点距離 32.00
Fナンバー 1.45
半画角（度） 23.12
レンズ全長 66.94
BF 11.20
INF 至近
d21 1.16 9.00
レンズ群データ
群 始面 焦点距離 レンズ構成長
1 1 38.15 49.77
2 22 83.21 4.82
近距離撮像倍率：-0.173
Aspheric surface data plane 21
K = 0.00000e + 000A 4 = 3.46800e-005 A 6 = -4.45749e-008 A 8 = 9.40073e-010 A10 = -3.72875e-012 A12 = 8.03246e-015
Various data
Wide angle
Focal length 32.00
F number 1.45
Half angle of view (degrees) 23.12
Lens total length 66.94
BF 11.20
INF Close
d21 1.16 9.00
Lens group data group Start surface Focal length Lens configuration length
1 1 38.15 49.77
2 22 83.21 4.82
Near-field imaging magnification: -0.173
数値データ３
単位 mm
面データ
面番号 r d nd νd θgF
1 -34.217 1.10 1.61340 44.3
2 51.992 1.16
3 137.147 6.98 1.91082 35.3
4 -22.754 1.00 1.85478 24.8
5 -69.791 0.30
6 28.676 5.32 1.91082 35.3
7 -257.267 0.30
8 33.160 6.27 1.59522 67.7 0.5442
9 -48.342 1.00 1.73800 32.3 0.5899
10 20.242 4.10
11(絞り) ∞ 4.08
12 -19.159 2.30 1.76385 48.5 0.5589
13 -12.686 0.72 1.67542 34.8 0.5825
14 179.943 0.30
15 32.368 7.65 1.88300 40.8
16 -15.173 0.78 1.67270 32.1
17 -43.332 1.53
18 -20.058 0.82 1.51742 52.4
19 40.757 3.81 1.85135 40.1
20* -120.561 (可変)
21 99.378 5.55 1.88300 40.8
22 -27.864 0.92 2.00069 25.5
23 -137.906 8.52
24 ∞ 1.75 1.54400 60.0
25 ∞ 1.55
像面 ∞
Numerical data 3
Unit mm
Surface data surface number rd nd d d θgF
1 -34.217 1.10 1.61340 44.3
2 51.992 1.16
3 137.147 6.98 1.91082 35.3
4-22.754 1.00 1.85478 24.8
5 -69.791 0.30
6 28.676 5.32 1.91082 35.3
7-257. 267 0.30
8 33.160 6.27 1.59522 67.7 0.5442
9 -48.342 1.00 1.73800 32.3 0.5899
10 20.242 4.10
11 (Aperture) 4.0 4.08
12 -19.159 2.30 1.76385 48.5 0.5589
13 -12.686 0.72 1.67542 34.8 0.5825
14 179.943 0.30
15 32.368 7.65 1.88300 40.8
16-15.173 0.78 1.67270 32.1
17-43.332 1.53
18-20.058 0.82 1.51742 52.4
19 40.753 3.81 1.85135 40.1
20 *-120.561 (variable)
21 993.78 5.55 1.88300 40.8
22-27.864 0.92 2.00069 25.5
23 -137.906 8.52
24 1. 1.75 1.54400 60.0
25 ∞ 1.55
Image plane ∞
非球面データ
第20面
K = 0.00000e+000 A 4= 2.83327e-005 A 6=-5.45082e-008 A 8= 1.10996e-009 A10=-7.56124e-012 A12= 2.06296e-014
各種データ
INF
焦点距離 32.34
Fナンバー 1.45
半画角（度） 22.90
レンズ全長 68.27
BF 11.20
INF 至近
d20 1.09 9.71
レンズ群データ
群 始面 焦点距離 レンズ構成長
1 1 38.54 49.51
2 21 84.58 6.47
近距離撮像倍率：-0.188
Aspheric surface data plane 20
K = 0.00000e + 000A 4 = 2.83327e-005 A 6 = -5.45082e-008 A 8 = 1.10996e-009 A10 = -7.56124e-012 A12 = 2.06296e-014
Various data
INF
Focal length 32.34
F number 1.45
Half angle of view (degrees) 22.90
Lens total length 68.27
BF 11.20
INF Close
d20 1.09 9.71
Lens group data group Start surface Focal length Lens configuration length
1 1 38.54 49.51
2 21 84.58 6.47
Near-field imaging magnification: -0.188
数値データ４
単位 mm
面データ
面番号 r d nd νd θgF
1 -34.023 1.10 1.61340 44.3
2 50.577 1.19
3 132.441 6.98 1.91082 35.3
4 -22.595 1.00 1.85478 24.8
5 -70.125 0.30
6 28.705 5.32 1.91082 35.3
7 -241.320 0.30
8 32.296 6.27 1.59282 68.6 0.5441
9 -47.599 1.00 1.73800 32.3 0.5899
10 19.941 4.16
11(絞り) ∞ 4.03
12 -19.667 2.30 1.74400 44.8 0.5655
13 -12.814 0.72 1.67542 34.8 0.5825
14 163.437 0.30
15 32.304 7.65 1.88300 40.8
16 -15.165 0.78 1.67270 32.1
17 -44.500 1.56
18 -20.105 0.82 1.51742 52.4
19 40.810 3.81 1.85135 40.1
20* -117.580 (可変)
21 97.529 5.55 1.88300 40.8
22 -26.508 0.92 2.00069 25.5
23 -134.491 8.52
24 ∞ 1.75 1.54400 60.0
25 ∞ 1.56
像面 ∞
Numerical data 4
Unit mm
Surface data surface number rd nd d d θgF
1-34.023 1.10 1.61340 44.3
2 50.577 1.19
3 132.441 6.98 1.91082 35.3
4-22.595 1.00 1.85478 24.8
5 -70.125 0.30
6 28.705 5.32 1.91082 35.3
7-241.320 0.30
8 32.296 6.27 1.59282 68.6 0.5441
9-47.599 1.00 1.73800 32.3 0.5899
10 19.941 4.16
11 (F-stop) 4.0 4.03
12 -19.667 2.30 1.74400 44.8 0.5655
13-12.814 0.72 1. 67542 34.8 0.5825
14 163.437 0.30
15 32.304 7.65 1.88300 40.8
16-15.165 0.78 1.67270 32.1
17 -44.500 1.56
18 -20.105 0.82 1.51742 52.4
19 40.810 3.81 1.85135 40.1
20 * -117.580 (variable)
21 97.529 5.55 1.88300 40.8
22 -26.508 0.92 2.00069 25.5
23 -134.491 8.52
24 1. 1.75 1.54400 60.0
25 1. 1.56
Image plane ∞
非球面データ
第20面
K = 0.00000e+000 A 4= 2.82111e-005 A 6=-6.19904e-008 A 8= 1.24472e-009 A10=-8.90674e-012 A12= 2.57258e-014
各種データ
焦点距離 32.40
Fナンバー 1.45
半画角（度） 22.86
レンズ全長 68.26
BF 11.20
INF 至近
d20 1.00 9.71
レンズ群データ
群 始面 焦点距離 レンズ構成長
1 1 38.70 49.59
2 21 83.62 6.47
近距離撮像倍率：-0.188
Aspheric surface data plane 20
K = 0.00000e + 000A 4 = 2.82111e-005 A 6 =-6. 19904e-008 A 8 = 1. 24472e-009 A10 =-8. 90674e-012 A12 = 2.57258e-014
Various data focal length 32.40
F number 1.45
Half angle of view (degrees) 22.86
Lens total length 68.26
BF 11.20
INF Close
d20 1.00 9.71
Lens group data group Start surface Focal length Lens configuration length
1 1 38.70 49.59
2 21 83.62 6.47
Near-field imaging magnification: -0.188
数値データ５
単位 mm
面データ
面番号 r d nd νd θgF
1 -34.023 1.10 1.61340 44.3
2 52.627 1.11
3 131.949 6.98 1.91082 35.3
4 -22.855 1.00 1.85478 24.8
5 -69.772 0.30
6 28.622 5.32 1.91082 35.3
7 -268.400 0.30
8 33.304 6.27 1.59522 67.7 0.5442
9 -47.947 1.00 1.73800 32.3 0.5899
10 20.085 4.23
11(絞り) ∞ 3.97
12 -19.016 2.30 1.76385 48.5 0.5589
13 -12.535 0.72 1.67542 34.8 0.5825
14 218.291 0.30
15 32.261 7.65 1.88300 40.8
16 -15.189 0.78 1.67270 32.1
17 -42.579 1.53
18 -19.870 0.82 1.51742 52.4
19 40.110 3.81 1.85135 40.1
20* -167.450 1.18
21 97.367 5.55 1.88300 40.8
22 -27.249 0.92 2.00069 25.5
23 -115.681 (可変)
24 ∞ 1.75 1.54400 60.0
25 ∞ 1.55
像面 ∞
Numerical data 5
Unit mm
Surface data surface number rd nd d d θgF
1-34.023 1.10 1.61340 44.3
2 52.627 1.11
3 131.949 6.98 1.91082 35.3
4 -22.855 1.00 1.85478 24.8
5 -69.772 0.30
6 28.622 5.32 1.91082 35.3
7 -268.400 0.30
8 33.304 6.27 1.59522 67.7 0.5442
9-47.947 1.00 1.73800 32.3 0.5899
10 20.085 4.23
11 (aperture) ∞ 3.97
12-19.016 2.30 1.76385 48.5 0.5589
13 -12.535 0.72 1.67542 34.8 0.5825
14 218.291 0.30
15 32.261 7.65 1.88300 40.8
16-15.189 0.78 1.67270 32.1
17-42.579 1.53
18 -19.870 0.82 1.51742 52.4
19 40.110 3.81 1.85135 40.1
20 * -167.450 1.18
21 97.367 5.55 1.88300 40.8
22-27.249 0.92 2.00069 25.5
23 -115.681 (variable)
24 1. 1.75 1.54400 60.0
25 ∞ 1.55
Image plane ∞
非球面データ
第20面
K = 0.00000e+000 A 4= 2.84400e-005 A 6=-5.05232e-008 A 8= 9.88419e-010 A10=-6.60991e-012 A12= 1.76998e-014
各種データ
INF
焦点距離 32.58
Fナンバー 1.45
半画角（度） 22.75
レンズ全長 68.33
BF 11.20
INF 至近
d23 8.52 11.81
レンズ群データ
群 始面 焦点距離 レンズ構成長
1 1 32.58 57.13
近距離撮像倍率：-0.101
Aspheric surface data plane 20
K = 0.00000e + 000A 4 = 2.84400e-005 A 6 =-5.05232-008 A 8 = 9.88419e-010 A10 = -6.60991e-012 A12 = 1.76998e-014
Various data
INF
Focal length 32.58
F number 1.45
Half angle of view (degrees) 22.75
Lens total length 68.33
BF 11.20
INF Close
d23 8.52 11.81
Lens group data group Start surface Focal length Lens configuration length
1 1 32.58 57.13
Near-field imaging magnification: -0.101
数値データ６
単位 mm
面データ
面番号 r d nd νd θgF
1 -33.557 1.10 1.61340 44.3
2 53.990 1.16
3 151.452 6.98 1.91082 35.3
4 -22.261 1.00 1.85478 24.8
5 -68.759 0.30
6 29.114 5.32 1.91082 35.3
7 -228.185 0.30
8 32.758 6.27 1.59282 68.6 0.5441
9 -46.226 1.00 1.73800 32.3 0.5899
10 20.399 4.08
11(絞り) ∞ 4.10
12 -18.889 2.30 1.76385 48.5 0.5589
13 -12.578 0.72 1.65412 39.7 0.5737
14 184.803 0.30
15 31.870 7.65 1.88300 40.8
16 -15.220 0.78 1.67270 32.1
17 -49.250 1.56
18 -20.733 0.82 1.54814 45.8
19 42.768 3.81 1.85135 40.1
20* -97.634 (可変)
21 84.211 5.55 1.88300 40.8
22 -27.365 0.92 2.00069 25.5
23 -167.024 8.52
24 ∞ 1.75 1.54400 60.0
25 ∞ 1.55
像面 ∞
Numerical data 6
Unit mm
Surface data surface number rd nd d d θgF
1-33.557 1.10 1.61340 44.3
2 53.990 1.16
3 151.452 6.98 1.91082 35.3
4 -22.261 1.00 1.85478 24.8
5-68.759 0.30
6 29.114 5.32 1.91082 35.3
7-228.185 0.30
8 32.758 6.27 1.59282 68.6 0.5441
9 -46.226 1.00 1.73800 32.3 0.5899
10 20. 399 4.08
11 (aperture) ∞ 4.10
12-18.88 2.30 1. 76385 48.5 0.5589
13-12.578 0.72 1.65412 39.7 0.5737
14 184.803 0.30
15 31.870 7.65 1.88300 40.8
16-15.220 0.78 1.67270 32.1
17 -49.250 1.56
18 -20.733 0.82 1.54814 45.8
19 42.768 3.81 1.85135 40.1
20 * -97.634 (variable)
21 84.211 5.55 1.88300 40.8
22-27.365 0.92 2.00069 25.5
23 -167.024 8.52
24 1. 1.75 1.54400 60.0
25 ∞ 1.55
Image plane ∞
非球面データ
第20面
K = 0.00000e+000 A 4= 2.85526e-005 A 6=-5.30617e-008 A 8= 1.07497e-009 A10=-7.29660e-012 A12= 1.99428e-014
各種データ
焦点距離 32.15
Fナンバー 1.45
半画角（度） 23.02
レンズ全長 68.22
BF 11.20
INF 至近
d20 1.00 9.72
レンズ群データ
群 始面 焦点距離 レンズ構成長
1 1 38.71 49.55
2 21 82.60 6.47
近距離撮像倍率：-0.187
Aspheric surface data plane 20
K = 0.00000e + 000A 4 = 2.85526e-005 A 6 =-5. 30617e-008 A 8 = 1.07497e-009 A10 = -7.29660e-012 A12 = 1.99428e-014
Various data focal length 32.15
F number 1.45
Half angle of view (degrees) 23.02
Lens total length 68.22
BF 11.20
INF Close
d20 1.00 9.72
Lens group data group Start surface Focal length Lens configuration length
1 1 38.71 49.55
2 21 82.60 6.47
Near field imaging magnification: -0.187
ＬＦ 接合レンズ ＬＲ 接合レンズ ＬＦＰ 正レンズ
ＬＦＮ 負レンズ ＬＲＰ 正レンズ ＬＲＮ 負レンズ
Ｌ１ 第１レンズ群 Ｌ２ 第２レンズ群
ＳＰ 開口絞り
LF cemented lens LR cemented lens LFP positive lens LFN negative lens LRP positive lens LRN negative lens L1 first lens group L2 second lens group SP aperture stop
Claims (11)
前記前群に含まれ前記開口絞りに隣接して配置されたレンズは、像側のレンズ面が凹形状であり、前記後群の最も物体側には接合レンズＬＲが配置され、
前記接合レンズＬＲは物体側のレンズ面が凹形状であり、負レンズＬＲＮと正レンズＬＲＰが接合されて構成されており、
前記負レンズＬＲＮと前記正レンズＬＲＰの材料のアッベ数を各々νｄｎＲ、νｄｐＲ、前記負レンズＬＲＮと前記正レンズＬＲＰの材料の部分分散比を各々θｇＦｎＲ、θｇＦｐＲとするとき、
θｇＦｎＲ−（−０．００２４０νｄｎＲ＋０．６６９４）＜０．０
３０．０＜νｄｎＲ
０．０＜θｇＦｐＲ−（−０．０００８３νｄｐＲ＋０．５９８１）
４２．０＜νｄｐＲ＜８０．０
なる条件式を満足することを特徴とする撮像光学系。 In an imaging optical system including a front group, an aperture stop, and a rear group disposed in order from an object side to an image side,
The lens included in the front group and disposed adjacent to the aperture stop has a concave lens surface on the image side, and the cemented lens LR is disposed on the most object side of the rear group.
The cemented lens LR has a concave lens surface on the object side, and is constructed by cementing a negative lens LRN and a positive lens LRP.
Assuming that the Abbe numbers of materials of the negative lens LRN and the positive lens LRP are dndnR, dpdpR, and partial dispersion ratios of the materials of the negative lens LRN and the positive lens LRP are θgFnR, θgFpR, respectively.
θ g F n R − (−0.00 240 dn d n R + 0.6 694) <0.0
30.0 <νdnR
0.0 <θgFpR − (− 0.00083νdpR + 0.5981)
42.0 <νdpR <80.0
An imaging optical system satisfying the following conditional expression.
ＮｄｎＲ−ＮｄｐＲ＜−０．０５
なる条件式を満足することを特徴とする請求項１に記載の撮像光学系。 When the refractive index of the material of the negative lens LRN is NdnR and the refractive index of the material of the positive lens LRP is NdpR,
NdnR-NdpR <-0.05
The imaging optical system according to claim 1, which satisfies the following conditional expression.
−３０．０＜νｄｎＲ−νｄｐＲ＜−５．０
なる条件式を満足することを特徴とする撮像光学系。 In the imaging optical system according to claim 1 or 2,
-30.0 <νdnR-νdpR <-5.0
An imaging optical system satisfying the following conditional expression.
−０．９５＜ｆＲ／ｆ＜−０．７０
なる条件式を満足することを特徴とする請求項１乃至３のいずれか１項に記載の撮像光学系。 When the focal length of the cemented lens LR is fR and the focal length of the whole system is f,
−0.95 <fR / f <−0.70
The imaging optical system according to any one of claims 1 to 3, wherein the following conditional expression is satisfied.
１．９０＜ＮｄＦＰ
なる条件式を満足する材料から構成される正レンズを有することを特徴とする請求項１乃至４のいずれか１項に記載の撮像光学系。 When the refractive index of the material of the positive lens included in the front group is NdFP, the front group is
1.90 <NdFP
The imaging optical system according to any one of claims 1 to 4, further comprising a positive lens made of a material that satisfies the following conditional expression.
前記負レンズＬＦＮと前記正レンズＬＦＰの材料のアッベ数を各々νｄｎＦ、νｄｐＦ、前記負レンズＬＦＮと前記正レンズＬＦＰの材料の部分分散比を各々θｇＦｎＦ、θｇＦｐＦとするとき、
θｇＦｎＦ−（−０．００２４０νｄｎＦ＋０．６６９４）＜０．０
３０．０＜νｄｎＦ
０．０＜θｇＦｐＦ−（−０．０００８３νｄｐＦ＋０．５９８１）
４２．０＜νｄｐＦ＜８０．０
なる条件式を満足することを特徴とする請求項１乃至５のいずれか１項に記載の撮像光学系。 The front group includes a cemented lens LF disposed adjacent to the aperture stop, and the cemented lens LF is configured by cementing a negative lens LFN and a positive lens LFP,
When the Abbe numbers of the materials of the negative lens LFN and the positive lens LFP are dndnF and dpdpF, and the partial dispersion ratios of the materials of the negative lens LFN and the positive lens LFP are θgFnF and θgFpF, respectively
θgFnF-(-0.00240 vdnF + 0.6694) <0.0
30.0 <νdnF
0.0 <θgFpF − (− 0.00083νdpF + 0.5981)
42.0 <νdpF <80.0
The imaging optical system according to any one of claims 1 to 5, wherein the following conditional expression is satisfied.
０．０５＜ＮｄｎＦ−ＮｄｐＦ
なる条件式を満足することを特徴とする請求項６または７に記載の撮像光学系。 When the refractive index of the material of the negative lens LFN is NdnF and the refractive index of the material of the positive lens LFP is NdpF,
0.05 <NdnF-NdpF
The imaging optical system according to claim 6 or 7, wherein the following conditional expression is satisfied.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2017081260A JP6991732B2 (en) | 2017-04-17 | 2017-04-17 | Imaging optical system and imaging equipment using it |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2017081260A JP6991732B2 (en) | 2017-04-17 | 2017-04-17 | Imaging optical system and imaging equipment using it |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2018180366A true JP2018180366A (en) | 2018-11-15 |
| JP6991732B2 JP6991732B2 (en) | 2022-02-03 |
Family
ID=64276591
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2017081260A Active JP6991732B2 (en) | 2017-04-17 | 2017-04-17 | Imaging optical system and imaging equipment using it |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6991732B2 (en) |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005351973A (en) * | 2004-06-08 | 2005-12-22 | Konica Minolta Business Technologies Inc | Reading lens |
| JP2008026593A (en) * | 2006-07-21 | 2008-02-07 | Fujinon Corp | Image reading lens, image reading optical system and image reader |
| JP2010266577A (en) * | 2009-05-13 | 2010-11-25 | Canon Inc | Optical system and optical apparatus having the same |
| JP2011013469A (en) * | 2009-07-02 | 2011-01-20 | Canon Inc | Optical system and optical apparatus including the same |
| JP2011053663A (en) * | 2009-08-04 | 2011-03-17 | Konica Minolta Opto Inc | Optical system, image projection apparatus including the same and image pickup device |
| JP2011253050A (en) * | 2010-06-02 | 2011-12-15 | Canon Inc | Optical system and optical equipment having the same |
| JP2013041205A (en) * | 2011-08-19 | 2013-02-28 | Fujifilm Corp | Image reading lens and image reading apparatus |
| JP2014081457A (en) * | 2012-10-16 | 2014-05-08 | Ricoh Imaging Co Ltd | Large diameter telephoto lens system |
| JP2015034892A (en) * | 2013-08-09 | 2015-02-19 | キヤノン株式会社 | Zoom lens |
| US20150241670A1 (en) * | 2012-11-19 | 2015-08-27 | Fujifilm Corporation | Projection zoom lens and projection type display device |
| DE102015112993B3 (en) * | 2015-08-06 | 2017-01-19 | Jos. Schneider Optische Werke Gmbh | Photographic lens |
| JP2017032809A (en) * | 2015-08-03 | 2017-02-09 | 株式会社シグマ | Imaging optics |
| JP2018005099A (en) * | 2016-07-07 | 2018-01-11 | 株式会社シグマ | Large-aperture lens |
-
2017
- 2017-04-17 JP JP2017081260A patent/JP6991732B2/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005351973A (en) * | 2004-06-08 | 2005-12-22 | Konica Minolta Business Technologies Inc | Reading lens |
| JP2008026593A (en) * | 2006-07-21 | 2008-02-07 | Fujinon Corp | Image reading lens, image reading optical system and image reader |
| JP2010266577A (en) * | 2009-05-13 | 2010-11-25 | Canon Inc | Optical system and optical apparatus having the same |
| JP2011013469A (en) * | 2009-07-02 | 2011-01-20 | Canon Inc | Optical system and optical apparatus including the same |
| JP2011053663A (en) * | 2009-08-04 | 2011-03-17 | Konica Minolta Opto Inc | Optical system, image projection apparatus including the same and image pickup device |
| JP2011253050A (en) * | 2010-06-02 | 2011-12-15 | Canon Inc | Optical system and optical equipment having the same |
| JP2013041205A (en) * | 2011-08-19 | 2013-02-28 | Fujifilm Corp | Image reading lens and image reading apparatus |
| JP2014081457A (en) * | 2012-10-16 | 2014-05-08 | Ricoh Imaging Co Ltd | Large diameter telephoto lens system |
| US20150241670A1 (en) * | 2012-11-19 | 2015-08-27 | Fujifilm Corporation | Projection zoom lens and projection type display device |
| JP2015034892A (en) * | 2013-08-09 | 2015-02-19 | キヤノン株式会社 | Zoom lens |
| JP2017032809A (en) * | 2015-08-03 | 2017-02-09 | 株式会社シグマ | Imaging optics |
| DE102015112993B3 (en) * | 2015-08-06 | 2017-01-19 | Jos. Schneider Optische Werke Gmbh | Photographic lens |
| JP2018005099A (en) * | 2016-07-07 | 2018-01-11 | 株式会社シグマ | Large-aperture lens |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6991732B2 (en) | 2022-02-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102401984B (en) | Telephoto lens system | |
| JP5932415B2 (en) | Optical system and imaging apparatus having the same | |
| US20090257125A1 (en) | Imaging lens, optical apparatus and method for forming image using this imaging lens | |
| US10670834B2 (en) | Zoom lens and image pickup apparatus | |
| JP2014041245A (en) | Zoom lens and imaging apparatus having the same | |
| JP7263122B2 (en) | Zoom lens and imaging device | |
| JP4289958B2 (en) | Zoom lens and imaging apparatus having the same | |
| JP2005215385A (en) | Zoom lens and imaging apparatus having the same | |
| JP2009276733A (en) | Zoom lens and imaging apparatus using the same | |
| JP7547083B2 (en) | Optical system and imaging device | |
| JP5127352B2 (en) | Zoom lens and imaging apparatus having the same | |
| US8248703B2 (en) | Zoom lens and optical apparatus having the zoom lens | |
| JP6546076B2 (en) | Wide-angle lens and imaging device | |
| JP4817551B2 (en) | Zoom lens | |
| JP2008158320A (en) | Zoom lens | |
| JP2010014897A (en) | Lens system and optical device | |
| JP5172247B2 (en) | Zoom lens | |
| CN111983792B (en) | Zoom lens and imaging apparatus including the same | |
| JP6549477B2 (en) | Wide-angle lens and imaging device | |
| JP5006637B2 (en) | Zoom lens and image projection apparatus having the same | |
| JP4537114B2 (en) | Zoom lens | |
| JP4902179B2 (en) | Zoom lens and imaging apparatus having the same | |
| JP2017161568A (en) | Zoom lens and imaging apparatus having the same | |
| JP2016191753A (en) | Zoom lens | |
| JP6995492B2 (en) | Imaging optical system and imaging equipment using it |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| RD01 | Notification of change of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7421 Effective date: 20191203 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20200401 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20210330 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20210406 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20210602 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20211109 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20211208 |
|
| R151 | Written notification of patent or utility model registration |
Ref document number: 6991732 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R151 |