Abstract: A differential subrange analog-to-digital converter (ADC) converts differential analog image signals received from sample and hold circuits to a digital signal through an ADC comparator. The comparator of the differential subrange ADC is shared by a successive approximation register (SAR) ADC coupled to provide both M upper output bits (UOB) and a ramp ADC coupled to provide N lower output bits (LOB). Digital-to-analog converters (DACs) of the differential subrange SAR ADC comprises 2M buffered bit capacitor fingers connected to the comparator. Each buffered bit capacitor finger comprises a bit capacitor, a bit buffer, and a bit switch controlled by the UOB. Both DACs are initialized to preset values and finalized based on the values of the least significant bit of the UOB. The subsequent ramp ADC operation will be ensured to have its first ramp signal ramps in a monotonic direction and its second ramp signal ramp in an opposite direction.

Abstract: A device includes a photodiode, a floating diffusion region, a transfer gate, and a channel region. The photodiode is disposed in a semiconductor material. The photodiode is coupled to generate charges in response to incident light. The photodiode has a substantially uniform doping profile throughout a depth of the photodiode in the semiconductor material. The floating diffusion region is disposed in the semiconductor material. The transfer gate is disposed between the photodiode and the floating diffusion region, wherein the transfer gate includes a plurality of fin structures. The channel region associated with the transfer gate is in the semiconductor material proximate to the transfer gate. The transfer gate is coupled to transfer the charge from the photodiode to the floating diffusion region through the channel region in response to a transfer signal coupled to be received by the transfer gate.

Abstract: A device includes a photodiode, a floating diffusion region, a transfer gate, and a channel region. The photodiode is disposed in a semiconductor material. The photodiode is coupled to generate charge in response to incident light. The floating diffusion region is disposed in the semiconductor material. The transfer gate is disposed between the photodiode and the floating diffusion region. The channel region associated with the transfer gate is in the semiconductor material proximate to the transfer gate. The transfer gate is coupled to transfer the charge from the photodiode to the floating diffusion region through the channel region in response to a transfer signal coupled to be received by the transfer gate. The transfer gate includes a plurality of fin structures that extend into the semiconductor material and the photodiode.

Abstract: A pixel array includes pixel cells, each including photodiodes. A source follower is coupled to generate an image signal in response image charge generated by the photodiodes. A first row select transistor is coupled to the source follower to output the image signal of the pixel cell. Pixel cells are organized into columns including a first column and a second column. The first row select transistors of the pixel cells of the first and second columns of pixel cells are coupled to first and second column bitlines, respectively. The pixel cells of the second column of pixel cells further include a second row select transistor coupled to the source follower to output the respective image signal to the first column bitline.

Abstract: The present application discloses an imaging system for detecting human-object interaction and a method for detecting human-object interaction thereof. The imaging system includes an event sensor, an image sensor, and a controller. The event sensor is configured obtain an event data set of the targeted scene according to variations of light intensity sensed by pixels of the event sensor when an event occurs in the targeted scene. The image sensor is configured capture a visual image of the targeted scene. The controller is configured to detect human according to the event data set, trigger the image sensor to capture the visual image when the human is detected, and detect the human-object interaction in the targeted scene according to the visual image and a series of event data sets obtained by the event sensor during the event.

Abstract: A pixel array includes pixel cells disposed in semiconductor material. Each of the pixel cells includes photodiodes, and a floating diffusion to receive image charge from the photodiodes. A source follower is coupled to the floating diffusion to generate an image signal in response image charge from the photodiodes. Drain regions of first and second row select transistors are coupled to a source of the source follower. A common junction is disposed in the semiconductor material between gates of the first and second row select transistors such that the drains of the first and second row select transistors are shared and coupled together through the semiconductor material of the common junction. The pixel cells are organized into a rows and columns with bitlines.

Abstract: An optical system comprises an imaging lens for imaging an object to an image and a sensing pixel array for detecting lights from the object toward the image. The sensing pixel array comprises a first sensing pixel and a second sensing pixel, each sensing pixel comprising a microlens covering a one-dimensional series of photodiodes having n photodiodes. A photodiode at an end of the one-dimensional series of photodiodes of the first sensing pixel detects a first light from the object toward the image, and a photodiode at an opposite end of the one-dimensional series of photodiodes of the second sensing pixel detects a second light from the object toward the image, where the first light and the second light pass opposite parts of the imaging lens.

Abstract: A pixel array for a high definition (HD) image sensor is disclosed. The pixel array includes a number of split pixel cells each including a first photodiode and a second photodiode that is more sensitive to incident light than the first photodiode. The first photodiode can be used to sense bright or high intensity light conditions, while the second photodiode can be used to sense low to medium intensity light conditions. In the disclosed pixel array, the sensitivity of one or more photodiodes is reduced by application of a light attenuation layer over the first photodiode of each split pixel cell. In accordance with methods of the disclosure, the light attenuation layer can be formed prior to the formation of a metal, optical isolation grid structure. This can lead to better control of the thickness and uniformity of light attenuation layer.

Abstract: An image sensor configured to resolve intensity and polarization has multiple pixels each having a single microlens adapted to focus light on a central photodiode surrounded by at least a first, a second, a third, and a fourth peripheral photodiodes, where a first polarizer at a first angle is disposed upon the first peripheral photodiode, a third polarizer at a third angle is disposed upon the third peripheral photodiode, a second polarizer at a second angle is disposed upon the second peripheral photodiode, and a fourth polarizer at a fourth angle is disposed upon the fourth peripheral photodiode, the first, second, third, and fourth angles being different. In embodiments, 4 or 8 peripheral photodiodes are provided, and in an embodiment the polarizers are parts of an octagonal polarizer.

Abstract: A pixel circuit includes a trench etched into a front side surface of a semiconductor substrate. The trench includes a bottom surface etched along a <100> crystalline plane and a tilted side surface etched along a <111> crystalline plane that extends between the bottom surface and the front side surface. A floating diffusion is disposed in the semiconductor substrate beneath the bottom surface of the trench. A photodiode is disposed in the semiconductor substrate beneath the tilted side surface of the trench and is separated from the floating diffusion. The photodiode is configured to photogenerate image charge in response to incident light. A tilted transfer gate is disposed over at least a portion of the bottom surface and at least a portion of the tilted side surface of the trench. The tilted transfer gate is configured to transfer the image charge from the photodiode to the floating diffusion.

Abstract: An arithmetic logic unit (ALU) includes a front end latch stage coupled to latch Gray code (GC) outputs of a GC generator in response to a comparator output. A signal latch stage is coupled to latch outputs of the front end latch stage. A GC to binary stage is coupled to generate a binary representation of the GC outputs latched in the signal latch stage. First inputs of an adder stage are coupled to receive outputs of the GC to binary stage. Outputs of the adder stage are generated in response to the first inputs and second inputs of the adder stage. A pre-latch stage is coupled to latch outputs of the adder stage. A feedback latch stage is coupled to latch outputs of the pre-latch stage. The second inputs of the adder stage are coupled to receive outputs of the feedback latch stage.

Abstract: A low power SRAM (static RAM) for an image sensor includes a voltage generation circuit for providing a positive supply voltage VP and a negative supply VN, wherein VDD>Vp>Vn>Vgnd; a plurality of memory cells coupled to a respective plurality of column sense lines in a pixel array, the plurality of memory cells receiving differential inputs dp and dn; and a Gray counter coupled to switchably couple VP and VN to the differential inputs dp and dn of the plurality of memory cells. A method of operating an image sensor with a low power SRAM includes acquiring an image by the image sensor; generating VP and VN such that VDD>VP>VN>Vgnd; receiving an output g of a column of pixels at a clock input of a memory cell; and switchably coupling VP and VN to the differential inputs dp and dn of a plurality of memory cells in the SRAM according to a codeword from a Gray counter.

Abstract: A ramp generator includes a plurality of switched current sources coupled in parallel between a resistor and ground. A digital ramp control signal generator includes a counter to generate a ramp control signal in response to a clock signal. Each bit of the ramp control signal is coupled to control switching of a respective one of the plurality of switched current sources to generate a ramp signal at an output of the ramp generator. The digital ramp control signal generator is coupled to receive a reset signal to zero the ramp control signal. The digital ramp control signal generator is further coupled to receive a set bits signal to initialize the ramp signal to a preset value after every reset of the ramp control signal to add a DC offset compensation current determined by the preset value to the ramp signal.

Abstract: A method of image sensor package fabrication includes forming a recess in a transparent substrate, depositing conductive traces in the recess, inserting an image sensor in the recess so that the image sensor is positioned in the recess to receive light through the transparent substrate, and inserting a circuit board in the recess so that the image sensor is positioned between the transparent substrate and the circuit board.

Abstract: Image sensors include a photodiode disposed in a semiconductor substrate and a transistor operatively coupled to the photodiode. At least three substrate trench structures are formed in the semiconductor substrate, defining two nonplanar structures, each having a plurality of sidewall portions. An isolation layer includes at least three isolation layer trench structures, each being disposed in a respective one of the three substrate trench structures. A gate includes three fingers, each being disposed in a respective one of the three isolation layer trench structures. An electron channel of the transistor extends along the plurality of sidewall portions of the two nonplanar structures in a channel width plane.

Abstract: Transistors include a pyramid-shaped gate trench defined by a triangular shape or a trapezoidal shape in a channel width plane and a trapezoidal shape in a channel length plane. Side wall portions of the pyramid-shaped gate trench form a channel having a triangular shape or a trapezoidal shape in the channel width plane. Advantageously, such transistors increase transconductance without increasing pixel width. Devices, image sensors, and pixels incorporating such transistors are also provided, in addition to methods of manufacturing the same.

Abstract: A method for detecting spoof fingerprints with an under-display fingerprint sensor includes illuminating, with incident light emitted from a display, a target region of a fingerprint sample disposed on a top surface of the display; detecting a first scattered signal from the fingerprint sample with a first image sensor region of an image sensor located beneath the display, the first image sensor region not directly beneath the target region, the first scattered signal including a first portion of the incident light scattered by the target region; determining a scattered light distribution based at least in part on the first scattered signal; and identifying spoof fingerprints based at least in part on the scattered light distribution.

Abstract: An imaging system includes a pixel array configured to generate image charge voltage signals in response to incident light received from an external scene. An infrared illumination source is deactivated during the capture of a first image of the external scene and activated during the capture of a second image of the external scene. An array of sample and hold circuits is coupled to the pixel array. Each sample and hold circuit is coupled to a respective pixel of the pixel array and includes first and second capacitors to store first and second image charge voltage signals of the captured first and second images, respectively. A column voltage domain differential amplifier is coupled to the first and second capacitors to determine a difference between the first and second image charge voltage signals to identify an object in a foreground of the external scene.

Abstract: Image sensors include a photodiode disposed in a semiconductor substrate and a transistor operatively coupled to the photodiode. The transistor includes a nonplanar structure disposed in the semiconductor substrate, which is bounded by two outer trench structures formed in the semiconductor substrate. Isolation deposits are disposed within the two outer trench structures formed in the semiconductor substrate. A gate includes a planar gate and two fingers extending into one of two inner trench structures formed in the semiconductor substrate between the nonplanar structure and a respective one of the two outer trench structures. This structure creates an electron channel extending along a plurality of sidewall portions of the nonplanar structure in a channel width plane.

Abstract: An image sensor module comprises an image sensor having a light sensing area, a cover glass for covering the light sensing area, a dam between the image sensor and the cover glass, which surrounds the light sensing area, and has an outer wall and an inner wall, where a cross-section of the inner wall parallel to the surface of the light sensing area of the image sensor forms a sawtooth pattern and/or, where a cross-section of the inner wall orthogonal to the surface of the light sensing area of the image sensor forms an inclined surface.