Camera module having geared lens barrel
View Patent ↗A camera having a housing, an imaging array positioned in said housing, and a lens assembly is disclosed. The lens assembly includes a fixed portion attached to the housing and a moveable portion connected to the fixed portion by a threaded coupling. The lens is positioned in the moveable portion to image a scene on the imaging array. The lens is separated from the imaging array by a distance that changes as the moveable portion is rotated relative to the fixed portion. The moveable portion includes a gear for applying a torque to the moveable portion such that the moveable portion moves relative to the fixed portion. The gear is preferably a spur gear. During the assembly of the camera, the gear is turned via a second gear such that the position of the lens is moved to a predetermined desired position.
1. A camera comprising:
a housing;
an imaging array positioned in said housing;
a lens assembly comprising a fixed portion attached to said housing and a moveable portion connected to said fixed portion by a threaded coupling and having a lens therein positioned to image a scene on said imaging array and separated from said imaging array by a distance that changes as said moveable portion is rotated relative to said fixed portion, said moveable portion including a gear, said moveable portion being permanently fixed to said fixed portion after said camera is assembled such that said moveable portion no longer moves relative to said fixed portion after said camera is assembled.
2. The camera of claim 1 wherein said gear is a spur gear.
3. The camera of claim 1 wherein said gear is a cycloid gear.
4. A method for setting the position of a lens relative to an imaging array in a camera to a desired position, said method comprising:
mounting said lens on a moveable barrel having a first near for rotating said barrel relative to a fixed housing containing said imaging array such that said position changes when said barrel is rotated;
imaging a test image on said imaging array with said lens and determining if said test image is in focus;
engaging said first gear with a second gear, external to said housing and said camera to cause said lens to move said lens;
imaging said test image on said imaging array after said movement to determine if said test image is now in focus; and
permanently immobilizing said barrel relative to said housing after said lens is moved to said desired position such that said barrel cannot move relative to said housing after said barrel is immobilized.
5. The method of claim 4 wherein said first and second gears are spur gears.
6. The method of claim 4 wherein said first and second gears are cycloid gears.