Title:
WIDE-ANGLE LENS
Document Type and Number:
Japanese Patent JP3500473
Kind Code:
B2
Abstract:
PURPOSE: To obtain a wide-angle lens which consists of a small number of elements and has long back focus.
CONSTITUTION: This wide-angle lens consists of the 1st lens group G11 which has negative refracting power on the whole and a 2nd lens group G12 which has positive refracting power on the whole in order from the object side, and at least one surface in the 1st lens group G11 is made aspherical, and, the power arrangement is optimized, a proper glass material is selected, and a proper lens shape is set, thereby obtaining an inverse telephoto type wide-angle lens which has the long back focus and is compact and excellently compensated in aberrations although the lens consists of a small number of elements and a small number of groups.
Inventors:
Tai Ogino
Application Number:
JP7640694A
Publication Date:
February 23, 2004
Filing Date:
March 24, 1994
Export Citation:
Assignee:
NIKON CORPORATION
International Classes:
G02B13/04; G02B13/18; (IPC1-7): G02B13/04; G02B13/18
Domestic Patent References:
| JP5249373A | ||||
| JP2256011A | ||||
| JP411209A | ||||
| JP585707A | ||||
| JP49101020A | ||||
| JP63136013A |