Optical filter and optical device

Abstract

An optical filter that is provided at an optical path between a photoelectric conversion device which converts a subject image formed at a light-receiving surface thereof to an electrical signal and an optical system which forms the subject image with a light flux from the subject at the photoelectric conversion device, to filter the light flux, includes a stage formed at, at least, a portion of an external circumference of the optical filter.

1 . An optical filter that is provided at an optical path between a photoelectric conversion device which converts a subject image formed at a light-receiving surface thereof to an electrical signal and an optical system which forms the subject image with a light flux from the subject at said photoelectric conversion device, to filter the light flux, comprising: 
 a stage formed at, at least, a portion of an external circumference of the optical filter.    
   
   
       2 . An optical filter according to  claim 1 , wherein: 
 a plurality of filter layers are laminated along a direction of an optical axis of the light flux that passes through; and    said stage is formed by varying a size of a surface of at least one filter layer along a direction perpendicular to the optical axis of the passing light flux from a size of a surface of another filter layer along a direction perpendicular to the optical axis.    
   
   
       3 . An optical filter according to  claim 1 , wherein: 
 said stage is utilized to hold the optical filter.    
   
   
       4 . An optical filter according to  claim 2 , wherein: 
 said stage is utilized to hold said optical filter.    
   
   
       5 . An optical device comprising: 
 a photoelectric conversion device that converts a subject image formed at a light-receiving surface thereof to an electric signal;    an optical system that forms the subject image with a light flux from a subject at the light-receiving surface of said photoelectric conversion device;    an optical filter that is provided on an optical path between said photoelectric conversion device and said optical system to filter the light flux; and    a holding member that holds said optical filter, wherein:    said optical filter comprises a stage formed at, at least, a portion of an external circumference of the optical filter and said stage is utilized to hold said optical filter element with said holding member.    
   
   
       6 . An optical device according to  claim 5 , wherein: 
 said holding member has a spring property and holds said optical filter by pressing said optical filter either toward said photoelectric conversion device or toward said optical system.