Patent ID: 11921343
Assignee: ZF FRIEDRICHSHAFEN AG
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. An optical system, comprising:
a substrate;
an image sensor on the substrate, the image sensor having an image plane;
a lens barrel defining a mechanical axis that intersects the image sensor and image plane, the lens barrel having first and second barrel portions that are integrally formed together so that the first and second barrel portions are constructed as a single piece, the first barrel portion including a flange from which the second barrel portion extends toward the substrate, the second barrel portion having a first coefficient of thermal expansion (CTE), the first barrel portion having a different CTE than the first CTE;
a lens mount integrally formed with the lens barrel so that the lens barrel and mount are constructed as a single piece, the lens mount engaging the flange and being connected to the substrate, the lens mount having a mount opening into which the second barrel portion extends, the lens mount having a second CTE; and
at least one lens element in the lens barrel on the mechanical axis and defining an optical axis that intersects the image sensor and image plane, a last powered optical surface of the at least one lens element being spaced along the optical axis from the image plane by a back focal length;
at least one of the second barrel portion having the first CTE and the lens mount having the second CTE limiting a change in the back focal length as a result of a change in temperature of the optical system to prevent defocusing and degradation of an image received by the image sensor.