JP2018180209A5

JP2018180209A5 -

Info

Publication number: JP2018180209A5
Application number: JP2017078053A
Authority: JP
Filing date: 2017-04-11
Publication date: 2020-05-14
Anticipated expiration: 2037-04-11

Description

本発明の光学系は、開口絞りを有する主レンズ系と、該開口絞りよりも像側の光路に対して挿抜可能に配置されたコンバータとを有する光学系であって、前記光学系の焦点距離は、前記コンバータが前記光路に挿抜されることで変化し、前記コンバータは、該コンバータの最も物体側に配置された負の屈折力のレンズ素子を含む複数のレンズ素子を備え、前記主レンズ系の焦点距離をｆｎ、前記主レンズ系のレンズ全長をＴＤｎ、前記コンバータが前記光路に挿入されたときの前記光学系のレンズ全長をＴＤｉとするとき、
０．５＜ＴＤｎ／ｆｎ＜１．２
０．９５＜ＴＤｎ／ＴＤｉ＜１．０５
なる条件式を満足することを特徴としている。 The optical system of the present invention is an optical system having a main lens system having an aperture stop, and than the opening stop is removably positioned with respect to the optical path of the image-side converter, the focus of the optical system distance varies by the converter is inserted into and removed from the optical path, said converter comprises a plurality of lens elements including a lens element of negative refractive power disposed closest to the object side of the converter, said main lens When the focal length of the system is fn, the total lens length of the main lens system is TDn, and the total lens length of the optical system when the converter is inserted in the optical path is TDi,
0.5 <TDn / fn <1.2
0.95 <TDn / TDi <1.05
It is characterized by satisfying the following conditional expression.

Claims

A main lens system having an aperture stop, an optical system having a removably arranged a converter with respect to the optical path of the image side of the aperture stop,
The focal length of the optical system changes when the converter is inserted into or removed from the optical path ,
The converter comprises a plurality of lens elements including a negative refractive power lens element disposed closest to the object side of the converter ,
When the focal length of the main lens system is fn, the total lens length of the main lens system is TDn, and the total lens length of the optical system when the converter is inserted in the optical path is TDi,
0.5 <TDn / fn <1.2
0.95 <TDn / TDi <1.05
An optical system characterized by satisfying the following conditional expression.

It said converter is inserted in the optical path between the front KiHiraki port aperture and said aperture stop lens elements arranged on the image side of the,
When the minimum effective diameter of the effective surface of the lens element arranged on the image side of the aperture stop is EAn and the effective diameter of the lens surface of the converter closest to the image side is EAi,
0.8 <EAn / EAi <1.5
The optical system according to claim 1, wherein the following conditional expression is satisfied.

Let EAi be the effective diameter of the lens surface of the converter closest to the image side, and let EAc be the diameter of the circle that is inscribed in the member that determines the effective diameter of the light beam that is arranged on the image side of the converter and that has the optical axis as the center. When
0.9 <EAc / EAi <5.0
The optical system according to claim 1 or 2, wherein the following conditional expression is satisfied.

When the focal length of the optical system when the converter is inserted in the optical path is fi,
1.2 <fn / fi <1.8
The optical system according to any one of claims 1 to 3, wherein the following conditional expression is satisfied.

Dexi the distance from the lens surface on the most image side of the converter to the image plane when said converter is inserted into the optical path, the distance from the aperture stop to the image plane when said converter is inserted into the optical path When using St,
0.3 <Dexi / St <0.8
The optical system according to any one of claims 1 to 4, wherein the following conditional expression is satisfied.

When fexn the focal length of the lens element refractive power of the front Kimake, the focal length of the optical system when the converter is inserted into the optical path and fi,
0.15 <-fexn / fi <0.50
The optical system according to any one of claims 1 to 5, wherein the following conditional expression is satisfied.

The converter was placed in order from the object side to the image side, the lens element of the negative refractive power, and having a lens element of positive refractive power according to any one of claims 1 to 6 Optical system.

The converter includes the negative refractive power lens element, the positive refractive power lens element, the negative refractive power lens element, and the positive refractive power lens element, which are arranged in order from the object side to the image side. The optical system according to any one of claims 1 to 6, wherein:

An optical system of any one of claims 1 to 8, the image pickup apparatus characterized by having an imaging element for receiving an image formed by the optical system.