| 摘要 |
PROBLEM TO BE SOLVED: To provide a projection optical system having a high optical performance by satisfactorily correcting the aberration fluctuation at focusing on an object at all-around distance from an object at infinity to an object at a close distance while maintaining the merit of a rearfocus retrofocus type, and to provide a projection type image display device using the projection optical system. SOLUTION: As for the projection optical system for magnifying and projecting an image, the system is constituted of a 1st lens group having a negative refractive power and a 2nd lens group having a positive refractive power in this order from the magnification side, focusing is performed by moving the 2nd lens group in an optical axis direction, and also, provided that the distance from a conjugate surface on the reduction side to a pupil is expressed by (t1) and the focal distance of the whole system is expressed by (f), the relation 0≤|f/t1|<0.2 is satisfied. COPYRIGHT: (C)2003,JPO
|
