Title:
ILLUMINATION DEVICE AND PROJECTION DEVICE
Document Type and Number:
Japanese Patent JP3880227
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain an illumination device that an illumination optical system can be small-sized in an optical axis direction without making the size of one frame of a lens array small by providing it with a first optical element where plural positive lenses are arranged, a second optical element where plural negative lenses are arranged and a third optical element where the plural positive lenses are arranged.
SOLUTION: The firs lens array (first optical element) 2 is constituted by arranging the plural lenses 2a having positive refractive power on a plate. The second lens array (second optical element) 3 is constituted by arranging the plural lenses 3a having negative refractive power on the plate. The third lens array (third optical element) 4 is constituted by arranging the plural lenses 4a having the positive refractive power on the plate. By constituting the part of the lens arrays of three lens arrays 2-4 having the refractive power of the positive, the negative and the positive in turn from a light source 1 side in such a way, the part of the lens arrays can be small-sized in the optical axis direction.
Inventors:
Saburo Sugawara
Application Number:
JP32888398A
Publication Date:
February 14, 2007
Filing Date:
November 04, 1998
Export Citation:
Assignee:
Canon Inc
International Classes:
G02B5/30; G02B13/16; G02B27/00; G02B27/12; G02B27/18; G02F1/13; G02F1/1335; G02F1/13357; G02F1/1347; G03B21/14; G03B33/12; (IPC1-7): G02B13/16; G02B5/30; G02B27/18; G02F1/13; G02F1/1335; G02F1/1347; G03B21/14; G03B33/12
Domestic Patent References:
| JP64061716A | ||||
| JP62199714U | ||||
| JP10288757A |
Foreign References:
| US3296923 |
Attorney, Agent or Firm:
Yukio Takanashi