CMOS active pixel with memory for imaging sensors
April 8, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesCMOS image sensor with pixel level A/D conversion Active pixel sensor with intra-pixel charge transfer Solid-state image taking apparatus including photodiode and circuit for converting output signal of the photodiode into signal which varies with time at variation rate depending on intensity of light applied to the photodiode Solid-state image sensor with focal-plane digital photon-counting pixel array Capacitively coupled successive approximation ultra low power analog-to-digital converter On-focal-plane analog-to-digital conversion for current-mode imaging devices Low noise amplifier for passive pixel CMOS imager Active pixel sensor array with multiresolution readout Active pixel image cell with embedded memory and pixel level signal processing capability Linearizing offset cancelling white balancing and gamma correcting analog to digital converter for active pixel sensor imagers with self calibrating and self adjusting properties InventorApplicationNo. 057429 filed on 04/08/1998US Classes:348/308, Including switching transistor and photocell at each pixel site (e.g., "MOS-type" image sensor)348/243Dark currentExaminersPrimary: Moe, AungForeign Patent References
International ClassesH04N 003/14H04N 005/335 AbstractAn imaging apparatus and a method of capturing and storing an image in digital form within a photosensitive area of the apparatus include integrating an array of memory cells within each pixel of the photosensitive area. Preferably, the memory cells are dual port memory cells, such that write operations can be performed in a parallel manner while reading operations are performed in a serial manner. In the preferred embodiment, each array contains a sufficient number of memory cells to store two digital words representing a photo signal and a reference signal. A comparator within each pixel operating in unison with a counter and a ramp generator captures the photo signal and the reference signal in digital form. The design of the imaging apparatus allows each pixel in the photosensitive area to capture and store the signals in a parallel manner. The parallel function of the apparatus increases the electronic shutter speed, while the integrated memory array eliminates the need for an external frame buffer memory.Field of SearchIncluding switching transistor and photocell at each pixel site (e.g., "MOS-type" image sensor)X - Y architecture Accumulation or integration time responsive to light or signal intensity Solid-state image sensor Including noise or undesired signal reduction Dark current CAMERA, SYSTEM AND DETAIL Plural photosensitive image detecting element arrays Photodiodes accessed by FETs Imaging array Including capacitor component Analog to digital conversion Using charge transfer devices (e.g., charge coupled devices, charge transfer by switched capacitances) Digital to analog conversion | |
