Abstract: Methods and apparatuses for calibration of phase detection auto focus (PDAF) camera systems are disclosed. In one aspect, the method involves capturing a first image of a scene at an initial lens position, the first image including a first left image and a first right image captured using left and right photodiodes. The method may also involve calculating an initial phase difference between the first left image and first right image and estimating an in-focus lens position based on the initial phase difference. The method may further involve moving the lens to a final lens position at which a final phase difference between a second left image and a second right image of a second image captured at the final lens position is substantially zero and calibrating the estimation of the in-focus lens position based on the initial lens position, the final lens position, and the initial phase difference.

Abstract: Provided are techniques for simulating a aperture in a digital imaging device, the aperture simulation generated by a multi-diode pixel image sensor. In one aspect, a method includes detecting light incident on a first light sensitive region on a first photodiode of a pixel, and detecting light incident on a second light sensitive region on a second photodiode of the pixel. The method further includes combining, for each pixel, signals from the first and second light sensitive regions, and generating, for a first aperture setting, a first image based at least in part on the light received from the first light sensitive region, and generating, for a second aperture setting, a second image based at least in part on the light received from the second light sensitive region.

Abstract: Devices and methods are disclosed for phase detection autofocus. In one aspect, an image capture device includes an image sensor, diodes, filter array, single-diode microlenses, multi-pixel-microlens, and an image signal processor. Each filter of the array positioned within proximity of one of the diodes and configured to pass light to the diode. Each single-diode microlens positioned within proximity of one of the filters. Each multi-pixel-microlens positioned within proximity of three adjacent filters. Two of the three filters may be configured to pass the same wavelengths of light to first and second diodes. One of the three filters may be disposed between the two filters and configured to pass different wavelengths of light to a third diode. The first and second diodes collect light incident in a first and second direction, respectively. The image signal processor performs phase detection autofocus based on values received from the first and second diodes.

Abstract: Systems, methods, and devices for optimizing phase detection autofocus (PDAF) processing are provided. One aspect provides an apparatus comprising: an image sensor configured to capture image data of a scene; a buffer; and a processor. The processor may be configured to store the image data in the buffer as a current frame and divide the current frame into a plurality of windows each corresponding to a different spatial region of the scene. The processor may be further configured to identify a central portion of the current frame comprising a subset of the plurality of windows. The processor may be further configured to determine a depth value of the central portion based on performing PDAF on the subset of the plurality of windows and determine a confidence value for the central portion based on the depth value and image data corresponding to the subset of the plurality of windows.

Abstract: An example image capture device includes an image sensor having diodes for sensing light from a target scene, a color filter array disposed above the diodes and including color filters each positioned over one of the diodes, single-diode microlenses positioned above some color filters arranged in a Bayer pattern, and multi-diode microlenses each positioned above at least two adjacent color filters that pass the same wavelengths of light to corresponding adjacent diodes below the color filters, each multi-diode microlens formed such that light incident in a first direction is collected one of the adjacent diodes and light incident in a second direction is collected in another of adjacent diodes. An image signal processor of the image capture device can perform phase detection autofocus using signals received from the adjacent diodes and can interpolate color values for the adjacent diodes.

Abstract: Systems, methods, and devices for optimizing phase detection autofocus (PDAF) processing are provided. One aspect provides an apparatus comprising: an image sensor configured to capture image data of a scene; a buffer; and a processor. The processor may be configured to store the image data in the buffer as a current frame and divide the current frame into a plurality of windows each corresponding to a different spatial region of the scene. The processor may be further configured to identify a central portion of the current frame comprising a subset of the plurality of windows. The processor may be further configured to determine a depth value of the central portion based on performing PDAF on the subset of the plurality of windows and determine a confidence value for the central portion based on the depth value and image data corresponding to the subset of the plurality of windows.

Abstract: Provided are techniques for simulating a aperture in a digital imaging device, the aperture simulation generated by a multi-diode pixel image sensor. In one aspect, a method includes detecting light incident on a first light sensitive region on a first photodiode of a pixel, and detecting light incident on a second light sensitive region on a second photodiode of the pixel. The method further includes combining, for each pixel, signals from the first and second light sensitive regions, and generating, for a first aperture setting, a first image based at least in part on the light received from the first light sensitive region, and generating, for a second aperture setting, a second image based at least in part on the light received from the second light sensitive region.

Abstract: Certain aspects relate to systems and techniques for using imaging pixels (that is, non-phase detection pixels) in addition to phase detection pixels for calculating autofocus information. Imaging pixel values can be used to interpolate a value at a phase detection pixel location. The interpolated value and a value received from the phase difference detection pixel can be used to obtain a virtual phase detection pixel value. The interpolated value, value received from the phase difference detection pixel, and the virtual phase detection pixel value can be used to obtain a phase difference detection signal indicating a shift direction (defocus direction) and a shift amount (defocus amount) of image focus.

Abstract: Methods and apparatuses for calibration of hybrid auto focus (AF) imaging systems are disclosed. In one aspect, a method is operable by an imaging device including a hybrid auto focus (AF) system comprising a lens. The method may include capturing an image of a scene, determining that the image of the scene is out of focus, and estimating, via a first AF process of the hybrid AF system, an initial lens position at which the image is in focus in response to determining that the image is out of focus; moving the lens to the initial lens position. The method may also include determining, via a second AF process of the hybrid AF system, a final lens position in response to the movement of the lens to the initial lens position and calibrating the first AF processes based on the determined final lens position.

Abstract: Certain aspects relate to systems and techniques for using imaging pixels (that is, non-phase detection pixels) for performing noise reduction on phase detection autofocus. Advantageously, this can provide for more accurate phase detection autofocus and also to optimized processor usage for performing phase detection. The phase difference detection pixels are provided to obtain a phase difference detection signal indicating a shift direction (defocus direction) and a shift amount (defocus amount) of image focus, and analysis of imaging pixel values can be used to estimate a level of focus of an in-focus region of interest and to limit the identified phase difference accordingly.

Abstract: Certain aspects relate to systems and techniques for using imaging pixels (that is, non-phase detection pixels) in addition to phase detection pixels for calculating autofocus information. Imaging pixel values can be used to interpolate a value at a phase detection pixel location. The interpolated value and a value received from the phase difference detection pixel can be used to obtain a virtual phase detection pixel value. The interpolated value, value received from the phase difference detection pixel, and the virtual phase detection pixel value can be used to obtain a phase difference detection signal indicating a shift direction (defocus direction) and a shift amount (defocus amount) of image focus.

Abstract: An example image capture device includes an image sensor having diodes for sensing light from a target scene, a color filter array disposed above the diodes and including color filters each positioned over one of the diodes, single-diode microlenses positioned above some color filters arranged in a Bayer pattern, and multi-diode microlenses each positioned above at least two adjacent color filters that pass the same wavelengths of light to corresponding adjacent diodes below the color filters, each multi-diode microlens formed such that light incident in a first direction is collected one of the adjacent diodes and light incident in a second direction is collected in another of adjacent diodes. An image signal processor of the image capture device can perform phase detection autofocus using signals received from the adjacent diodes and can interpolate color values for the adjacent diodes.

Abstract: Certain aspects relate to systems and techniques for using imaging pixels (that is, non-phase detection pixels) for performing noise reduction on phase detection autofocus. Advantageously, this can provide for more accurate phase detection autofocus and also to optimized processor usage for performing phase detection. The phase difference detection pixels are provided to obtain a phase difference detection signal indicating a shift direction (defocus direction) and a shift amount (defocus amount) of image focus, and analysis of imaging pixel values can be used to estimate a level of focus of an in-focus region of interest and to limit the identified phase difference accordingly.

Abstract: Certain aspects relate to systems and techniques for using imaging pixels (that is, non-phase detection pixels) for performing noise reduction on phase detection autofocus. Advantageously, this can provide for more accurate phase detection autofocus and also to optimized processor usage for performing phase detection. The phase difference detection pixels are provided to obtain a phase difference detection signal indicating a shift direction (defocus direction) and a shift amount (defocus amount) of image focus, and analysis of imaging pixel values can be used to estimate a level of focus of an in-focus region of interest and to limit the identified phase difference accordingly.