Zoom and focus control method and system
AssigneeHewlett-Packard Development Company, L.P.
InventorsMichelle Ogg, David K. Campbell, Gregory V. Hofer, Masahiro Ohno, Yoshihiro Yamazaki
Life of this patent
Estimating the term…
Abstract
A focus lens and a zoom lens group having a first zoom lens and a second zoom lens are controlled separately from one another in an internal-focus camera. The positions of the focus lens and the second zoom lens in the zoom lens group are tracked, and are controlled to approach no closer to one another than a minimum safe distance to avert collisions between the focus lens and the second zoom lens.
Claims19
A method for controlling a lens group having a focus lens and a zoom lens group along an optical axis, where the zoom lens group includes at least one zoom lens, comprising:
- receiving input to change the position of a selected one of the focus lens and the zoom lens group;
- and
- separately controlling the positions of the focus lens and the zoom lens group along the optical axis such that the focus lens and the second zoom lens approach substantially no closer to one another than a selected minimum safe distance.
A method for controlling a lens group having a focus lens and a zoom lens group along an optical axis, where the zoom lens group has a first zoom lens and a second zoom lens, comprising:
- receiving input to change the position of the focus lens;
- determining the initial position of the second zoom lens;
- determining a permissible working range by subtracting a minimum safe distance from said initial position of said second zoom lens;
- selecting a focus figure of merit;
- moving the focus lens in one direction along the optical axis;
- tracking the position of the focus lens along the optical axis;
- if the focus figure of merit increases, moving the focus lens again in said one direction to a final position, said moving performed no further than a boundary of said permissible working range;
- and
- if the focus figure of merit decreases, moving the focus lens again in a direction opposite said one direction to a final position, said moving performed no further than a boundary of said permissible working range.
A method for controlling a lens group having a focus lens and a zoom lens group along an optical axis, where the zoom lens group has a first zoom lens and a second zoom lens, comprising:
- receiving input to change the position of the zoom lens group;
- and
- determining the initial position of the focus lens and the focal distance associated with said initial position;
- determining the initial position of the second zoom lens;
- moving the second zoom lens a discrete amount along the optical axis to a new position in the direction associated with said received input;
- determining a permissible working range along the optical axis;
- moving the focus lens to the best focus position within said permissible working range, wherein the best focus position within said permissible working range achieves focus for said initial focus distance at said new position of said second zoom lens;
- and
- repeating said moving the second zoom lens, said determining a permissible working range and said moving the focus lens until the second zoom lens has reached a final position associated with said received input.
Dependencies are inferred from the claim text.