Camera system, interchangeable lens and method of manufacturing interchangeable lens

Abstract

A camera system having a predetermined image circle, comprises: an interchangeable lens having a lens mount portion; and a camera body having an image sensor that is disposed within that image circle, and a body mount portion, wherein, when a radius of circular portion at a maximum internal diameter part of an opening portion of the lens mount portion is termed rM, a flange back that is a distance from the lens mount portion to a light reception surface of an image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the diameter of the image circle is termed D, the following equations are satisfied: 14.0 mm≦2 rM ≦40.0 mm  Conditional Expression #1 16.0 mm≦ da ≦20.0 mm  Conditional Expression #2 14.0 mm≦ D ≦20.0 mm  Conditional Expression #3.

1 . A camera system having a predetermined image circle, comprising:
 an interchangeable lens having a lens mount portion for attachment to a camera body and that is capable of forming an image within that image circle; and   a camera body having an image sensor that is disposed within that image circle, and a body mount portion for attaching an interchangeable lens so that it is disposed at a position separated by a predetermined distance from a light reception surface of the image sensor,   wherein, when a radius of circular portion at a maximum internal diameter part of an opening portion of the lens mount portion is termed rM, a flange back that is a distance from the lens mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and a diameter of the image circle is termed D, the following equations are satisfied:
   14.0 mm≦2 rM≦ 40.0 mm  Conditional Expression #1
 
   16.0 mm≦ da≦ 20.0 mm  Conditional Expression #2
 
   14.0 mm≦ D≦ 20.0 mm  Conditional Expression #3.
 
   
     
     
         2 . The camera system according to  claim 1 , wherein, when a distance upon the optical axis from the lens mount portion to the lens surface closest to the image is termed L (in case the lens mount portion is taken as a reference, the direction towards the image being considered positive and the direction towards the object to be photographed being considered negative), the following equations are satisfied:
     L≦ 11.0 mm  Conditional Expression #4.
   
     
     
         3 . The camera system according to  claim 1 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the following equation is satisfied:
   18.0 mm≦2 rM≦ 34.0 mm  Conditional Expression #1A.
   
     
     
         4 . The camera system according to  claim 1 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equation is satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5.
   
     
     
         5 . The camera system according to  claim 1 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equations are satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
     2 rM/da≧ 0.7  Conditional Expression #6.
   
     
     
         6 . The camera system according to  claim 1 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equations are satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
     2 rM/da≧ 0.8  Conditional Expression #6A.
   
     
     
         7 . The camera system according to  claim 1 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical of the interchangeable lens to the camera body is termed F-number, the following equations are satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
     2 rM/da≧ 1.0  Conditional Expression #6B.
   
     
     
         8 . An interchangeable lens comprising:
 a lens mount portion for attachment to a camera body; and   an optical system for focusing an object image on a light reception plane of an image sensor;   wherein, the interchangeable lens is capable to be attached to the camera body that has a camera body mount portion and the image sensor whose whole pixels generate imaging signals can fit inside of a circle having a diameter in a range from 14.0 mm to 20.0 mm, and,   when a maximum internal diameter part of an opening portion of the lens mount portion is termed rM and a flange back that is a distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, the following equations are satisfied:
   14.0 mm≦2 rM≦ 40.0 mm  Conditional Expression #1
 
   16.0 mm≦ da≦ 20.0 mm  Conditional Expression #2.
 
   
     
     
         9 . The interchangeable lens according to  claim 8 , wherein, when a distance upon the optical axis from the lens mount portion to the lens surface closest to the image is termed L (in case the lens mount portion is taken as a reference, the direction towards the image being considered positive and the direction towards the object to be photographed being considered negative), the following equation is satisfied:
     L≦ 11.0 mm  Conditional Expression #4.
   
     
     
         10 . The interchangeable lens according to  claim 8 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the following equation is satisfied:
   18.0 mm≦2 rM≦ 34.0 mm  Conditional Expression #1A.
   
     
     
         11 . The interchangeable lens according to  claim 8 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equation is satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5.
   
     
     
         12 . The interchangeable lens according to  claim 8 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equations are satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
     2 rM/da≧ 0.7  Conditional Expression #6.
   
     
     
         13 . The interchangeable lens according to  claim 8 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equations are satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
     2 rM/da≧ 0.8  Conditional Expression #6A.
   
     
     
         14 . The interchangeable lens according to  claim 8 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical of the interchangeable lens to the camera body is termed F-number, the following equations are satisfied:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
     2 rM/da≧ 1.0  Conditional Expression #6B.
   
     
     
         15 . An interchangeable lens comprising:
 a lens mount portion for attachment to a camera body; and   an optical system for focusing an object image on a light reception plane of an image sensor;   wherein, the interchangeable lens is capable to be attached to the camera body that has a camera body mount portion and an image sensor whose whole pixels generate imaging signals can fit inside of a circle having a diameter in a range from 14.0 mm to 20.0 mm, and,   when a maximum internal diameter part of an opening portion of the lens mount portion is termed rM and a distance from the lens mount portion to an image surface of the optical system is termed dB, the following equations are satisfied:
   14.0 mm≦2 rM≦ 40.0 mm  Conditional Expression #1
 
   14.8 mm≦ dB≦ 18.8 mm  Conditional Expression #2-2.
 
   
     
     
         16 . The interchangeable lens according to  claim 15 , wherein, when a distance upon the optical axis from the lens mount portion to the lens surface closest to the image is termed L (in case the lens mount portion is taken as a reference, the direction towards the image being considered positive and the direction towards the object to be photographed being considered negative), the following equation is satisfied:
     L≦ 11.0 mm  Conditional Expression #4.
   
     
     
         17 . The interchangeable lens according to  claim 15 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the following equation is satisfied:
   18.0 mm≦2 rM≦ 34.0 mm  Conditional Expression #1A.
   
     
     
         18 . The interchangeable lens according to  claim 15 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equation is satisfied:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2.
   
     
     
         19 . The interchangeable lens according to  claim 15 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equations are satisfied:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2
     2 rM/dB≧ 0.7  Conditional Expression #6-2.
   
     
     
         20 . The interchangeable lens according to  claim 15 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical system of the interchangeable lens is termed F-number, the following equations are satisfied:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2
     2 rM/dB≧ 0.8  Conditional Expression #6-2A.
   
     
     
         21 . The interchangeable lens according to  claim 15 , wherein, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical of the interchangeable lens to the camera body is termed F-number, the following equations are satisfied:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2
     2 rM/dB≧ 1.0  Conditional Expression #6-2B.
   
     
     
         22 . A method of manufacturing an interchangeable lens that is capable to be attached to the camera body that has a camera body mount portion and the image sensor whose whole pixels generate imaging signals can fit inside of a circle having a diameter in a range from 14.0 mm to 20.0 mm, comprising:
 when a maximum internal diameter part of an opening portion of the lens mount portion is termed rM and a flange back that is a distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, forming a lens mount so as to be satisfied the following equations:
   14.0 mm≦2 rM≦ 40.0 mm  Conditional Expression #1
 
   16.0 mm≦ da≦ 20.0 mm  Conditional Expression #2, and
 
   assembling the interchangeable lens by combining the lens mount with an optical system.   
     
     
         23 . A method of manufacturing an interchangeable lens according to  claim 22 , further comprising, when a distance upon the optical axis from the lens mount portion to the lens surface closest to the image is termed L (in case the lens mount portion is taken as a reference, the direction towards the image being considered positive and the direction towards the object to be photographed being considered negative),
 forming a lens mount so as to be satisfied the following equation:
     L≦ 11.0 mm  Conditional Expression #4.
 
   
     
     
         24 . A method of manufacturing an interchangeable lens according to  claim 22 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM,
 forming a lens mount so as to be satisfied the following equation:
   18.0 mm≦2 rM≦ 34.0 mm  Conditional Expression #1A.
 
   
     
     
         25 . A method of manufacturing an interchangeable lens according to  claim 22 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number,
 forming a lens mount so as to be satisfied the following equation:
   2 rM/da≧ 1 /F -number  Conditional Expression #5.
 
   
     
     
         26 . A method of manufacturing an interchangeable lens according to  claim 22 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number,
 forming a lens mount so as to be satisfied the following equations:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
 
   2 rM/da≧ 0.7  Conditional Expression #6.
 
   
     
     
         27 . A method of manufacturing an interchangeable lens according to  claim 22 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical system of the interchangeable lens is termed F-number,
 forming a lens mount so as to be satisfied the following equations:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
 
   2 rM/da≧ 0.8  Conditional Expression #6A.
 
   
     
     
         28 . A method of manufacturing an interchangeable lens according to  claim 22 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the flange back that is the distance upon the optical axis from the body mount portion to the light reception surface of the image sensor in a state that the interchangeable lens and the camera body are mutually engaged is termed da, and the aperture ratio of the optical of the interchangeable lens to the camera body is termed F-number,
 forming a lens mount so as to be satisfied the following equations:
   2 rM/da≧ 1 /F -number  Conditional Expression #5
 
   2 rM/da≧ 1.0  Conditional Expression #6B.
 
   
     
     
         29 . A method of manufacturing an interchangeable lens that is capable to be attached to the camera body that has a camera body mount portion and the image sensor whose whole pixels generate imaging signals can fit inside of a circle having a diameter in a range from 14.0 mm to 20.0 mm, comprising:
 when a maximum internal diameter part of an opening portion of the lens mount portion is termed rM and a distance from the lens mount portion to an image surface of the optical system is termed dB,   forming a lens mount so as to be satisfied the following equations:
   14.0 mm≦2 rM≦ 40.0 mm  Conditional Expression #1
 
   14.8 mm≦ dB≦ 18.8 mm  Conditional Expression #2-2, and
 
   assembling the interchangeable lens by combining the lens mount with an optical system.   
     
     
         30 . A method of manufacturing an interchangeable lens according to  claim 29 , further comprising, when a distance upon the optical axis from the lens mount portion to the lens surface closest to the image is termed L (in case the lens mount portion is taken as a reference, the direction towards the image being considered positive and the direction towards the object to be photographed being considered negative),
 forming a lens mount so as to be satisfied the following equation:
     L≦ 11.0 mm  Conditional Expression #4.
 
   
     
     
         31 . A method of manufacturing an interchangeable lens according to  claim 29 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM,
 forming a lens mount so as to be satisfied the following equation:
   18.0 mm≦2 rM≦ 34.0 mm  Conditional Expression #1A.
 
   
     
     
         32 . A method of manufacturing an interchangeable lens according to  claim 29 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical system of the interchangeable lens is termed F-number,
 forming a lens mount so as to be satisfied the following equation:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2.
 
   
     
     
         33 . A method of manufacturing an interchangeable lens according to  claim 29 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical system of the interchangeable lens is termed F-number,
 forming a lens mount so as to be satisfied the following equations:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2
 
   2 rM/dB≧ 0.7  Conditional Expression #6-2.
 
   
     
     
         34 . A method of manufacturing an interchangeable lens according to  claim 29 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical system of the interchangeable lens is termed F-number,
 forming a lens mount so as to be satisfied the following equations:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2
 
   2 rM/dB≧ 0.8  Conditional Expression #6-2A.
 
   
     
     
         35 . A method of manufacturing an interchangeable lens according to  claim 29 , further comprising, when the maximum internal diameter part of the opening portion of the lens mount portion is termed rM, the distance from the lens mount portion to the image surface of the optical system is termed dB, and the aperture ratio of the optical of the interchangeable lens to the camera body is termed F-number,
 forming a lens mount so as to be satisfied the following equations:
   2 rM/dB≧ 1 /F -number  Conditional Expression #5-2
 
   2 rM/dB≧ 1.0  Conditional Expression #6-2B.