Abstract: A system and method of generating a color correction matrix (CCM) for an image sensor are disclosed. Quantum efficiency (QE) spectra of pixels of the image sensor illuminated by a physical light source are measured. Subsequently, color values of the image sensor and color values in a predetermined color space are determined according to the QE spectra and predetermined reference data essential for deriving the color values. Finally, the CCM for the image sensor is generated by applying a fitting algorithm on the color values of the image sensor and the color values in the predetermined color space.

Abstract: The present invention provides an image sensor and a fabricating method thereof capable of approaching higher quantum efficiency and reducing cost. The method comprises: providing a substrate; forming a pixel region on a top surface of the substrate; forming an interlayer insulating layer and at least a metal line on the pixel region; forming an isolation carrier layer having a hole array therein on the interlayer insulating layer; grinding a lower surface of the substrate to reduce the thickness of the substrate; placing a plurality of conductors into the hole array to form a plurality of bumps on the isolation carrier layer.

Abstract: A process and structure of a backside illumination (BSI) image sensor are disclosed. An n-type doped region is formed in a substrate, and a transfer gate is formed on top of the semiconductor substrate. A p-type doped region is formed in the n-type doped region either using the transfer gate as a mask or is non-self aligned formed.

Abstract: The present invention provides an image sensor. The image sensor comprises a plurality of pixels. Each pixel comprises an optical element and at least a dummy metal segment disposed above the optical element, wherein the dummy metal segment is not directly above the optical element. The image sensor includes a dummy metal segment with a size different from a size of another dummy metal segment included in the image sensor.

Abstract: The present invention provides an image sensor. The image sensor comprises: a substrate, a plurality of optical elements, a first insulation layer, an anti-reflective coating (ARC) layer, a second insulation layer, and a color filter array. The optical elements are disposed in the substrate. The first insulation layer is disposed on the substrate and the optical elements. The ARC layer is disposed on the first insulation layer. The second insulation layer is disposed on the ARC layer. The color filter array is disposed on the second insulation layer, and the color filter array comprises a plurality of color filters corresponding to a plurality of different colors of light, respectively. The ARC layer comprises a plurality of sections directly below the color filters in a vertical direction, respectively, and the sections have different inherent reflection characteristics. The image sensor of the present invention can increase sensitivity and reduce crosstalk.

Abstract: A method for pixel color correction includes the steps of determining a gray degree of a designated pixel; generating an adjusted color correction matrix according to the gray degree of the designated pixel; and applying the adjusted color correction matrix to the designated pixel to correct color errors of the designated pixel. The gray degree is generated according to a ratio of the chrominance information to the luminance information. A weighted sum of a reference color correction matrix and a unity matrix is calculated to generate the adjusted color correction matrix, and weighting factors of the reference color correction matrix and the unity matrix are determined by the gray degree, wherein the unity matrix is a fundamental matrix without color correction.

Abstract: A signal chain of an imaging system is disclosed. The system includes three circuit stages. The first circuit stage includes a programmable gain amplifier (PGA) and a black level compensation (BLC) circuit that form a BLC loop. The second circuit stage includes an analog-to-digital converter (ADC), where a dark signal offset is added at an input of the ADC. The third circuit stage includes a digital gain circuit and a digital loop that makes a final output of the imaging system settle on a target level in the BLC mode.

Abstract: A process and structure of a back side illumination (BSI) image sensor are disclosed. An n-type doped region is formed in a substrate, and a transfer gate is formed on top of the semiconductor substrate. A p-type doped region is formed in the n-type doped region either using the transfer gate as a mask or is non-self aligned formed.

Abstract: A sensing pixel array is provided and includes a plurality of pixels disposed in an array. Each pixel operates during an exposure period and a readout period and generates a readout signal. Each pixel includes a sensing unit and a sampling unit. The sensing unit senses light to generate a sensing signal during the exposure period. The sampling unit samples the sensing signal to generate a sensing output signal which serves as the readout signal during the readout period. During the exposure period, the sampling unit acts as a memory unit for storing an input signal and outputting an accessed output signal which serves as the readout signal.

Abstract: A pipelined recycling analog-to-digital converter (ADC), which converts a first analog input signal into a first digital output signal, including a first conversion stage and a second conversion stage is disclosed. The first conversion stage includes a first processing unit and a second processing unit. The first and the second processing units execute a number of conversion operations. For each conversion operation, an analog value and a digital code are generated by the first or the second processing unit. The first and the second processing units share an operational amplifier, and for each conversion operation. The second conversion stage includes a comparing unit which determines a specific analog value among the analog values generated by the first and the second processing units. When the specific analog value is not located within a predetermined range, the comparing unit generates a reset pulse to reset the operational amplifier.

Abstract: Multi-phase black level calibration (BLC) methods and systems are generally disclosed. According to one embodiment of the present invention, an image sensor comprises a pixel sensor array, a timing generator, and a front-end processing block. The front-end processing block also includes a first summing junction, a first BLC block, and a second BLC block. According to a first timing signal from the timing generator, the first BLC block is configured to iteratively generate a first calibration signal in a first phase based on a first set of adjusted black level signals associated with a first set of black pixels, a changing accumulator step, and a predetermined condition associated with a first target black level. According to a second timing signal from the timing generator, the second BLC block is configured to generate a second calibration signal for a second summing junction to apply to an image signal associated with one or more active pixels in the frame in a second phase.

Abstract: A pixel circuit of a CMOS image sensor is disclosed. At least two transfer transistors are configured to transfer integrated light signals of corresponding photodetectors to a first node. A reset transistor is configured to reset the first node to a predetermined reset voltage of a second node, and a source follower is configured to buffer the integrated light signals. In one embodiment, a capacitor is further connected between the first node and the second node to minimize influence of the effective capacitance including capacitance of a floating diffusion region and parasitic capacitance due to the photodetector and the transfer transistor.

Abstract: A readout circuit for an image sensor is disclosed. At least one column amplifier (CA) generates a CA reset signal when the column amplifier is reset. A capacitor and a switch are configured to receive a column of the image sensor. A multiplexer is coupled between (a) the capacitor and the switch and (b) an input of the column amplifier. A correlated double sampling (CDS) circuit is used for controllably receiving an output of the column amplifier.

Abstract: Apparatus and method for pattern interpolation are disclosed. Horizontally interpolated green, red and blue pixel values, and vertically interpolated green, red and blue pixel values are generated according to the pixels received from a pattern color filter. Subsequently, a direction is selected for the green value interpolation according to the horizontally and vertically interpolated pixel values.

Abstract: Apparatus and method for gamma correction are disclosed. An adjustable blending unit is utilized for adjustably blending a linear gamma function with a nonlinear gamma function, thereby resulting in an adjustable gamma curve. The nonlinear gamma function is adjustable by a blending parameter such that distance of the gamma curve to linear gamma curve may be changed.

Abstract: An image sensing device is disclosed, including an epitaxy layer having the a conductivity type, including a first pixel area corresponding to a first incident light, a second pixel area corresponding to a second incident light, and a third pixel area corresponding to a third incident light, wherein the wavelength of the first incident light is longer than that of the second incident light and the wavelength of the second incident light is longer than that of the third incident light. A photodiode is disposed in an upper portion of the epitaxy layer, and a first deep well for reducing pixel-to-pixel talk of the image sensing device is disposed in a lower portion of the epitaxy layer in the second pixel area and the third pixel area, wherein at least a portion of the epitaxy layer in first pixel area does not include the first deep well.

Abstract: A readout system with enhanced dynamic range for an image sensor is constructed with a pixel circuit and a readout circuit. The pixel circuit includes at least a first amplifier with a first gain and a second amplifier with a second gain for amplifying signals from the image sensor. The readout circuit includes at least a first readout sub-circuit and a second readout sub-circuit for corresponding reading output of the first amplifier and output of the second amplifier respectively.

Abstract: A binning circuit and method for an image sensor is disclosed. A column amplifier (CA) is first reset, and thus generates a CA reset signal. A capacitor and a switch network are coupled between an output of the image sensor and an input of the column amplifier. A correlated double sampling (CDS) circuit controllably receives the output of the column amplifier. The switch network is controlled in a way such that an image signal of a first group of the image sensor is transmitted and stored in the CDS circuit, and an image signal of a second group is then added to the stored image signal of the first group.

Abstract: A scheme is provided that enhances the dynamic range performance of images via multiple readouts during one exposure. The readout process circuit structure includes at least an analog-to-digital converter (ADC). The analog-to-digital converter converts analog data generated from an image sensor into digital data, allowing sub-frame readouts for improving a dynamic range of the image sensor. Additionally, methods of partial digitization (not a full number of bits) and image array are provided.

Abstract: A black level compensation (BLC) circuit is disclosed. The BLC circuit includes a switched-capacitor (SC) integrator configured to compensate a readout amplifier of an image sensor. An output of the readout amplifier is clamped to a reference voltage at which a black level of the image sensor is defined. According to one aspect, a bad pixel detector is used to detect a bad pixel or pixels and disconnect the BLC loop when the bad pixel or pixels are detected.