Patent
1989-10-06
1991-03-05
Sugarman, Scott J.
G02B 1514
Patent
active
049972650
ABSTRACT:
A zoom lens for a variable power copying apparatus comprises six lenses disposed in order from an object surface to an image surface. A first lens is composed of a negative lens having an object side oriented concave surface. A second lens is composed of a positive lens. A third lens is composed of a negative lens having an object side oriented concave surface. An aperture stop is disposed between the third lens and a fourth lens. The fourth lens is composed of the same lens as the third lens and having an image side oriented concave surface. A fifth lens is composed of the same lens as the second lens. And a sixth lens is composed of the same lens as the first lens and having an image side oriented concave surface. For a natural size image of an object, the first to sixth lenses are arranged symmetrically with respect to the aperture stop. For a reduced or magnified size image of an object, the lens groups and the aperture stop are arranged in such a way that the first and sixth lenses are fixed, that the second and fifth lenses are moved nonsymmetrically and that the whole lens system is moved along the optical axis so that the image size is continuously varied keeping the conjugate length between the object and the image constant regardless of the scale.
REFERENCES:
patent: 4813773 (1989-03-01), Minefuji
Ricoh & Company, Ltd.
Sugarman Scott J.
LandOfFree
Zoom lens for variable power copying apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Zoom lens for variable power copying apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Zoom lens for variable power copying apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-492845