Zoom lens device, optical device comprising the same, and projector
AssigneeSeiko Epson Corporation
InventorsShuji Narimatsu, Akitaka Yajima
Life of this patent
Estimating the term…
Abstract
A zoom lens device 10 includes lenses 11, 12, 13, 14, and 15. The third lens group 13 (compensator lens group) is disposed between two lens groups (the second and fourth lens groups 12 and 14) forming a variator lens group. The two lens groups (the second and fourth lens groups 12 and 14) forming the variator lens group are retained by a common variator-lens frame 22 and are moved together. Accordingly, a zoom lens device, an optical apparatus, and a projector can be provided in which, even when a plurality of lens groups are assembled, degradation of optical characteristics due to decentering between the lens groups can be prevented.
Claims9
A zoom lens device comprising:
- a variator lens group which includes two lens groups, which move along the optical axis during a zooming operation;
- and
- a compensator lens group which is disposed between the two lens groups and which moves in association with the variator lens group along the optical axis,
- wherein the two lens groups are retained by a common variator-lens frame and are constructed such that the two lens groups move together.
Dependencies are inferred from the claim text.