Abstract: Imaging systems may be provided with stacked-chip image sensors and adjustable lens systems. A stacked-chip image sensor may include a vertical chip stack that includes an array of image pixels and processing circuitry. The adjustable lens system may pass light from a scene onto the image pixels at a number of focus positions. The image pixels may capture a focus bracket of image frames at a capture frame rate for light passed by the adjustable lens system at two or more of the focus positions. The processing circuitry may combine a set of image frames in the focus bracket to generate a focused image. The focused image may have one or more portions of the captured scene in focus. The processing circuitry may output the focused image to off-chip image processing circuitry at an output frame rate that is less than the capture frame rate.

Abstract: Imaging systems may be provided with stacked-chip image sensors. A stacked-chip image sensor may include a vertical chip stack that includes an array of image pixels, analog control circuitry and storage and processing circuitry. The control circuitry or the processing circuitry may include metadata generation circuitry and image data output control circuitry that control the processing of blocks of image data from blocks of image pixels in the image pixel array. The metadata generation circuitry may generate metadata for a current image block and provide the generated metadata to the image data output control circuitry. The image data output control circuitry may output image blocks that have been flagged for readout, flagged for enhanced image processing, or otherwise flagged for transmission in the generated metadata.

Abstract: An electronic device may have one or more analog-to-digital converters (ADCs). The ADCs may be used in digitizing signals from an image sensor. In order to ensure that input signals received by an ADC are not clipped, the input signals may be positively or negatively offset by a desired amount. Offsetting the input signals may ensure that the offset input signals wall within the acceptable input range of the ADCs. Offset injection may be accomplished using capacitors that are also used for analog-to-digital conversion. As an example, the ADC may be a successive approximation-type ADC that uses capacitors in a binary search for the digital value most accurately representing an input analog value. The capacitors of the ADC may be used for the successive approximation process and for offset injection. The offset injection may be digitally canceled out following digitization of the input analog signal.

Abstract: Electronic devices may include camera modules. A camera module may include an anamorphic lens and an image sensor having an array of asymmetrical image pixels. The array may be a square array arranged in pixel columns and pixel rows. The square image pixel array may include more pixel columns than pixel rows and may be located completely within the image circle of the anamorphic lens. The asymmetrical image pixels may each have a width that is smaller the height of that image pixel. The asymmetrical image pixels may be rectangular image pixels or diamond-shaped image pixels. The anamorphic lens may project a distorted image onto the array of asymmetrical image pixels. The width of each asymmetrical image pixel may be smaller than the height of that image pixel by an amount that corresponds to the distortion of the image by the anamorphic lens.

Abstract: An imager may include depth sensing pixels that receive and convert incident light into image signals. The imager may have an associated imaging lens that focuses the incident light onto the imager. Each of the depth sensing pixels may include a microlens that focuses incident light received from the imaging lens through a color filter onto first and second photosensitive regions of a substrate. The first and second photosensitive regions may provide different and asymmetrical angular responses to incident light. Depth information for each depth sensing pixel may be determined based on the difference between output signals of the first and second photosensitive regions of that depth sensing pixel. Color information for each depth sensing pixel may be determined from a summation of output signals of the first and second photosensitive regions.

Abstract: Electronic devices may be provided with image sensors and light sources. The image sensors may include image pixels each having a photosensitive element, first and second storage nodes, and first and second transfer transistors coupled between the photosensitive element and the first and second storage nodes. The first and second transfer transistors may be synchronized with the light source so that charges generated by the photosensitive element of each image pixel when the light source is on are transferred to the first storage node of that pixel and charges generated by the photosensitive element of each image pixel when the light source is off are transferred to the second storage node of that pixel. The light source may be an oscillating light source that is configured to turn on and off multiple times during an image exposure. The generated charges may be used in flash-matting operations.

Abstract: An imaging device capable of simultaneously capturing visible and infrared images may be provided with an array of photosensitive elements, an array of filter elements arranged over the array of photosensitive elements, and a dual bandpass filter arranged over the array of filter elements. The dual bandpass filter may have a first passband in the visible spectral range and a second passband in the infrared spectral range. The array of filter elements may include color filter elements and infrared filter elements. During color image capturing operations, each color pixel receives visible and near infrared light through the dual bandpass filter and an associated color filter element. The infrared portion of the pixel signal from the color pixels may be removed using signals from the near infrared pixels. During infrared image capturing operations, each near infrared pixel receives infrared light through the dual bandpass filter and an associated infrared filter element.

Abstract: An image sensor such as a backside illumination image sensor may be provided with analog circuitry, digital circuitry, and an image pixel array on a semiconductor substrate. Trench isolation structures may separate the analog circuitry from the digital circuitry on the substrate. The trench isolation structures may be formed from dielectric-filled trenches in the substrate that isolate the portion of the substrate having the analog circuitry from the portion of the substrate having the digital circuitry. The trench isolation structures may prevent digital circuit operations such as switching operations from negatively affecting the performance of the analog circuitry. Additional trench isolation structures may be interposed between portions of the substrate on which bond pads are formed and other portions of the substrate to prevent capacitive coupling between the bond pad structures and the substrate, thereby enhancing the high frequency operations of the image sensor.

Abstract: Electronic devices may have camera modules that include an image sensor and processing circuitry. The image sensor may capture an image from a scene. The processing circuitry may extract image statistics and exposure levels from the image. The processing circuitry may use the image statistics and the exposure levels to generate a first exposure time, a second exposure time, and gain settings for the image sensor. The image sensor may capture additional images from the scene having long-exposure image pixel values that are captured using the first exposure time and short-exposure image pixel values that are captured using the second exposure time. The processing circuitry may generate a long-exposure image and a short-exposure image from the second image. The processing circuitry may generate auto-exposed high-dynamic-range images of the scene using the long-exposure image and the short-exposure image.

Abstract: An electronic device may have a camera module. The camera module may capture images having an initial depth of field. The electronic device may receive user input selecting a focal plane and an effective f-stop for use in producing a modified image with a reduced depth of field. The electronic device may include image processing circuitry that selectively blurs various regions of a captured image, with each region being blurred to an amount that varies with distance to the user selected focal plane and in response to the user selected effective f-stop (e.g., a user selected level of depth of field).

Abstract: An image sensor may be provided having a pixel array that includes optical cavity image pixels. An optical cavity image pixel may include a photosensitive element in a substrate and a reflective cavity formed from a frontside reflector that is embedded in an intermetal dielectric stack, a backside reflector formed in a dielectric layer above the photosensor that partially covers the photosensor, and sidewall reflectors formed in the substrate between adjacent photosensors using deep trench isolation techniques. Each optical cavity image pixel may also include a light-guide trench above the photosensor that guides light into the reflective cavity for that pixel. Each optical cavity pixel may also include color filter material in the trench. Light that is guided into the reflective cavity by the light-guide trench may experience multiple reflections from the reflectors of the reflective cavity before being absorbed and detected by the photosensor.

Abstract: An electronic device may have a camera module. The camera module may capture images. The electronic device may include image processing circuitry that color corrects the images. The image processing circuitry may desaturate the images globally and/or spatially based on global and/or spatial noise levels of the image. The image processing circuitry may desaturate the images substantially without changing the hue of the images. The image processing circuitry may generate a color correction matrix with constant hue in real time and may color correct images in real time as the images are captured by the camera module.

Abstract: Electronic devices may include image sensors. Image sensors may be used to capture images having rows of long-exposure image pixel values that are interleaved with rows of short-exposure image pixel values. The long-exposure and short-exposure values in each interleaved image frame may be interpolated to form interpolated values. A combined long-exposure image and a combined short-exposure image may be generated using the long-exposure and the short-exposure values from the interleaved image frames and the interpolated values from a selected one of the interleaved image frames. The combined long-exposure and short-exposure images may each include image pixel values from either of the interleaved image frames in a non-motion edge region and image pixel values based only on the image pixel values or the interpolated values from the selected one of the interleaved images in a motion or non-edge region. High-dynamic-range images may be generated using the combined long-exposure and short-exposure images.