Auto-focus in low-profile folded optics multi-camera system

摘要

An image capturing system and a method of autofocusing are disclosed such that, for example, when a folded optics configuration is used, a field corrector lens can be placed on the image sensor of the system and a plurality of lenses can be placed perpendicular to the image sensor. The plurality of lenses can be movable relative to the image sensor such that acceptable MTF curve performances can be obtained when the image capturing system is focused at reference distances.

主权项

1. An image capture system comprising:
a plurality of cameras configured to capture a corresponding plurality of portions of a target image scene, a camera of the plurality of cameras comprising:
an image sensor;a primary light folding surface configured to redirect light representing one portion of the corresponding plurality of portions of the target image scene in a first direction toward the image sensor;an optical element having an input surface configured to receive the light from the primary light folding surface, a secondary light folding surface configured to redirect the light in a second direction toward the image sensor, and an output surface through which light redirected by the secondary light folding surface propagates in the second direction toward the image sensor;a lens assembly comprising:
a stationary portion having a first surface connected to the output surface of the optical element and a second surface connected to the image sensor, wherein the stationary portion of the lens assembly comprises a field corrector lens, anda movable portion positioned between the primary light folding surface and the optical element;an actuator configured to move the movable portion of the lens assembly along the first direction;at least one guide rail coupled to the actuator and the movable portion of the lens assembly, the at least one guide rail positioned to slidably engage another surface within the camera to constrain motion of the movable portion of the lens assembly away from an optical axis or rotating around the optical axis, the optical axis substantially parallel to the first direction; anda processor configured to generate a final image of the target image scene based at least partly on the corresponding plurality of portions.