Photographic optical system
First Claim
1. A photographic optical system comprising in order from the object side:
- a front lens unit which comprises at least a negative lens element and has negative refractive power as a whole; and
a rear lens unit which comprises at least two positive lens elements and at least a negative lens element, and has positive refractive power as a whole, wherein a reflecting member to fold an optical path and an aperture stop are disposed in order from the object side between said front lens unit and said rear lens unit, and wherein said photographic optical system satisfies the following conditions (1) and (2);
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Accused Products
Abstract
A photographic optical system comprising a front lens unit which comprises at least a negative lens element and has negative refractive power as a whole, a rear lens unit which comprises at least two positive lens elements and at least a negative lens element and has positive refractive power as a whole as well as a reflecting member to fold an optical path and an aperture stop which are disposed between the front lens unit and the rear lens unit, and has an adequately defined focal length of the front lens nit and an adequately defined distance along an optical axis between the front lens unit to the aperture stop. This photographic optical system is composed of a small number of lens elements, has a large field angle and exhibits favorable optical performance.
63 Citations
25 Claims
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1. A photographic optical system comprising in order from the object side:
- a front lens unit which comprises at least a negative lens element and has negative refractive power as a whole; and
a rear lens unit which comprises at least two positive lens elements and at least a negative lens element, and has positive refractive power as a whole, wherein a reflecting member to fold an optical path and an aperture stop are disposed in order from the object side between said front lens unit and said rear lens unit, and wherein said photographic optical system satisfies the following conditions (1) and (2);
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 17, 18, 19, 20, 21, 22, 23, 24, 25)
- a front lens unit which comprises at least a negative lens element and has negative refractive power as a whole; and
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10. A photographic optical system comprising in order from the object side;
- a front lens unit which comprises at least a negative lens element and has negative refractive power as a whole; and
a rear lens unit which comprises at least a positive lens element and has positive refractive power as a whole, wherein said optical system has an image pickup surface formed by said photographic optical system, wherein said optical system has a reflecting member to fold an optical path which is disposed between said front lens unit and said rear lens unit, and wherein said photographic optical system is focused by changing a distance along the optical axis between said front lens unit and said image pickup surface. - View Dependent Claims (15, 16)
- a front lens unit which comprises at least a negative lens element and has negative refractive power as a whole; and
Specification