Himax Imaging, Inc.

Chi-Shao Lin

Amit Mittra

Fang-Ming Huang

Yu-Ping Hu

Ping-Hung Yin

Yang Wu

Chung-Wei Chang

Chih-Min Liu

Nguyen Dong

Chang-Wei Chang

Black level calibration methods and systems are generally disclosed. According to one embodiment of the present invention, a method of calibrating a black level signal in a frame includes performing an iteration of averaging a first set of digital values corresponding to a first set of adjusted black level signals associated with a first set of black pixels of the frame, determining whether an average value based on the first set of digital values has reached a target black level, determining a calibration offset based on a difference between the average value and the target black level and an accumulator step, converting the calibration offset to an analog signal, generating a calibration signal based on the analog signal for a second set of black pixels of the frame, and repeating the iteration for the frame until a predetermined condition is determined to have been met.

Black level calibration method and system

A method for forming an image sensing device is disclosed. An epitaxy layer having the first conductivity type is formed on a substrate, wherein the epitaxy layer comprises 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. A first deep well is formed in a lower portion of the epitaxy layer for reducing pixel-to-pixel talk of the image sensing device. A second deep well is formed in a lower portion of the epitaxy layer.

Method for forming an image sensing device

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.

Image sensing device and fabrication thereof

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.

Signal chain of an imaging system

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.

Back side illumination image sensor and a process thereof

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.

Low noise pixel readout circuit with high conversion gain

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.

Growing community of inventors

Tainan, Taiwan

Chi-Shao Lin