Viewing apparatus having a photographic function
AssigneePENTAX Corporation
InventorTetsuya Abe
Life of this patent
Estimating the term…
Abstract
A viewing apparatus with a photographing function, includes a viewing optical system by which an image of an object, formed by a positive objective optical system, is viewed though a positive eyepiece optical system, and a photographing optical system which is provided independently from the viewing optical system. The photographing optical system covers substantially the same field of view as that of the viewing optical system. The viewing apparatus satisfies the following condition: 0.1<ft/fo<0.7 (1) wherein ft designates the focal length of the photographing optical system, and fo designates the focal length of the objective optical system of the viewing optical system.
Claims9
A viewing apparatus with a photographing function the viewing apparatus comprising:
- a viewing optical system comprising a positive objective optical system and an eyepiece optical system, in this order from an object;
- and
- a photographing optical system comprising a positive first lens group comprising a positive lens element and a negative lens element, and a positive second lens group comprising a positive lens element and a negative lens element;
- wherein an image of an object, formed by said positive objective optical system, is viewed though said eyepiece optical system;
- wherein said photographing optical system is provided independently from said viewing optical system, and said photographing optical system covers substantially the same field of view as that of said viewing optical system;
- wherein said viewing apparatus satisfies the following condition:
- 0.1<ft/fo<0.7
- and
- wherein said photographing optical system satisfies the following condition:
- 0.15<DI-II/f<0.6
- wherein
- ft designates the focal length of said photographing optical system of said viewing apparatus,
- fo designates the focal length of said objective optical system of said viewing optical system,
- DI-II designates the distance between said positive first lens group and said positive second lens group, and
- f designates the focal length of said entire photographing optical system.
Dependencies are inferred from the claim text.