Title:
ILLUMINATION OPTICAL SYSTEM, AND PROJECTION TYPE IMAGE DISPLAY DEVICE USING THE SAME
Document Type and Number:
Japanese Patent JP2002296538
Kind Code:
A
Abstract:
To provide an illumination optical system varying the size of an illumination range with a simple constitution.
The illumination optical system illuminating an image display element with a luminous flux from a light source is provided with a negative meniscus lens convex to the light source side and a biconvex positive lens on a light source side. By changing the interval of the two lenses, the size of an illumination area in the image display element is changed.
Inventors:
SUGAWARA SABURO
Application Number:
JP2001096018A
Publication Date:
October 09, 2002
Filing Date:
March 29, 2001
Export Citation:
Assignee:
CANON KK
International Classes:
G02B19/00; G02B15/14; G02B27/18; G03B21/00; G03B21/14; (IPC1-7): G02B27/18; G02B15/14; G02B19/00; G03B21/00; G03B21/14
Domestic Patent References:
| JPH05323190A | 1993-12-07 | |||
| JPH09184979A | 1997-07-15 |
Foreign References:
| US5860721A | 1999-01-19 |
Attorney, Agent or Firm:
Keizo Nishiyama (1 person outside)