Apple Inc.

Michael Chin

Ralph T Brunner

Yingjun Bai

Touraj Tajbakhsh

Abhishek Dhanda

Gregory Guyomarc'h

Mark N Gamadia

Ling Xiao Wang

Various embodiments include synchronization of camera focus movement control with frame capture. In some embodiments, such synchronization may comprise synchronized focus movement control that is based at least in part on integration timing and/or region of interest (ROI) timing. According to some examples, an actuator of a camera module may be controlled such that a lens group and/or an image sensor of the camera module move towards a focus position during one or more time periods (e.g., a non-integration time period in which the image sensor is not being exposed, a non-ROI time period in which a ROI of the image sensor is not being exposed for image capture, and/or a blanking interval, etc.). Additionally, or alternatively, the actuator may be controlled such that the lens group and the image sensor do not move relative to each other in a focus direction during one or more other time periods (e.g., an integration time period in which the image sensor is being exposed, a ROI time period in which the ROI of the image sensor is being exposed, etc.).

Synchronization of camera focus movement control with frame capture

This disclosure pertains to systems, methods, and computer readable media for performing lens shading correction (LSC) operations that modulate gains based on scene lux level and lens focus distance. These gains compensate for both color lens shading (i.e., the deviation between R, G, and B channels) and vignetting (i.e., the drop off in pixel intensity around the edges of an image). As scene illuminance increases, the sensor captures more signal from the actual scene, and the lens shading effects begin to appear. To deal with the situation, the lens shading gains are configured to adaptively 'scale down' when scene lux approaches zero and 'scale up' when scene lux changes from near zero to become larger. The lens shading gain may also be modulated based on the focus distance. For optical systems without zoom, the inventors have discovered that the amount of lens shading fall off changes as focus distance changes.

Lens shading modulation

Systems, methods, and computer readable media to provide improved autofocus operations are described. In general, techniques are disclosed that show how to improve contrast-based autofocus operations by applying a novel threshold-and-select action to window-specific focus scores. More particularly, techniques disclosed herein may evaluate a multi-window autofocus area over a burst collected group of images. For each captured image, focus scores for each window within an autofocus area may be collected, aggregated and then consolidated to identify a single focus metric and its associated lens position for each window. The window-specific focus scores may be reviewed and selection of a 'best' autofocus lens position made using a selection criteria. The specified criteria may be used to bias the selection to either a front-of-plane (macro) or back-of-plane (infinity) focus position.

Autofocus

An apparatus, method, and computer readable medium related to autofocusing a camera lens system. An initial image is captured at a first lens position and focus information is extracted with respect to a first plurality of focus windows. A second image is captured at a second lens position and focus information is extracted for a second plurality of focus windows that correspond to the first plurality of focus windows in the initial image. The focus information for corresponding windows is compared to determine whether the focus status in each window is improving or degrading; this determination reveals whether the lens is positioned in a desirable position with respect to the data revealed by the data extracted from the focus windows.

Growing community of inventors

Belmont, CA, United States of America

Michael Chin