Projection lens and projector with magnifying function

摘要

A projection lens includes a first lens group having negative refractive power, a second lens group having positive refractive power, a third lens group having negative refractive power, a fourth lens group having negative refractive power, a fifth lens group having positive refractive power, and a sixth lens group having positive refractive power, in sequence from an enlargement conjugate side, the projection lens performing magnification by changing the spacing between the lens groups, wherein at the time of magnification from the telephoto end to the wide-angle end, the second, third, fourth, and fifth lens groups are moved, and an aperture stop is arranged between the surface of the third lens group closest to a reduction conjugate side and the surface of the fifth lens group closest to the enlargement conjugate side.

主权项

1. A projection lens comprising a first lens group having negative refractive power, a second lens group having positive refractive power, a third lens group having negative refractive power, a fourth lens group having negative refractive power, a fifth lens group having positive refractive power, and a sixth lens group having positive refractive power, in sequence from an enlargement conjugate side, the projection lens performing magnification by changing the spacing between the lens groups, wherein
at the time of magnification from the telephoto end to the wide-angle end, the second, third, fourth, and fifth lens groups are moved, an aperture stop is arranged between the surface of the third lens group closest to a reduction conjugate side and the surface of the fifth lens group closest to the enlargement conjugate side, and the following conditional expressions (1) and (2) are satisfied:
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