Patent application number | Description | Published |
20080217545 | Compact CMOS-Based X-Ray Detector Adapted for Dental Applications - An image sensor having a two-dimensional array of pixel sensors, a layer of scintillation material, and a controller is disclosed. The layer of scintillation material is adjacent to the two-dimensional array, the scintillation material emits light in response to x-rays impinging thereon. The pixel sensors detect this light. The controller reads out data stored in the two-dimensional array of pixel sensors and forms an image therefrom. The controller corrects the data for errors resulting from x-rays that generate electrons that are stored in the pixel sensors in the process of forming the image. In one aspect of the invention, the controller forms the image by causing the two-dimensional array to form a plurality of frames, each frame includes a measurement of a charge stored on each photodiode during a preceding time period. The controller selectively combines data from the frames to form the image. | 09-11-2008 |
20090108207 | CMOS Sensor Adapted for Dental X-Ray Imaging - An image sensor and a method for using the same to capture an x-ray image are disclosed. The image sensor includes an output bus, a two dimensional array of pixel sensors that receives light from a layer of scintillation material and a controller. Each pixel sensor includes a capacitor, a plurality of light sensors, a charge converter and a transfer gate. Each of the light sensors includes a photodiode and a photodiode transfer gate that connects the photodiode to the capacitor. During readout, the charge on selected ones of the photodiodes is transferred to the capacitor. The charge on the capacitor is converted to a signal that is coupled to the output bus through the transfer gate by the controller. The number of photodiodes that are connected to the capacitor during the readout can be controlled to assure that the charge converter does not saturate. | 04-30-2009 |
20090108311 | CMOS Detector with Reduced Sensitivity to X-Rays - An imaging array and method for operating the same is disclosed. The imaging array includes a semiconductor substrate having an epitaxial layer of semiconductor material deposited on a first surface thereof. A plurality of photodiodes is formed in a top surface of the epitaxial layer. The imaging array also includes a depletion layer underlying the photodiodes and disposed between the epitaxial layer and the semiconductor substrate. The depletion layer is connected to a power rail for removing electrons collected in the depletion layer. The depletion layer collects electrons generated by x-ray interactions in the substrate. The depletion layer can also be biased such that the depletion layer collects electrons collected by the photodiodes to provide a reset operation for the imaging array. The current flowing through the depletion layer can be used to generate a trigger signal indicating the start of an x-ray exposure. | 04-30-2009 |
20090109313 | Self-Triggering CMOS Image Sensor - An image sensor and method for using the image sensor to capture an image are disclosed. The image sensor includes an imaging array, a first block amplifier and a controller. A first plurality of pixels in the imaging array includes pixels having a photodiode connected to a first node by a gate transistor, a reset transistor connected between the first node and a reset node, a pixel amplifier having an input connected to the first node and an output, and an output gate for connecting the pixel amplifier output to an output bus. The sensor has a monitoring mode and an image capture mode. In the monitoring mode the reset node is connected to the first block amplifier whose output is monitored and used to trigger the image capture mode when the output exceeds a predetermined threshold. | 04-30-2009 |
20090230436 | CMOS Image Sensor with Improved Fill-Factor and Reduced Dark Current - A photosensor and an imaging array utilizing the same are disclosed. The photosensor includes a light conversion region that has separate charge storage regions. The light conversion region includes a plurality of separate charge storage regions within a doped region, each charge collection region being doped such that the mobile charges generated by light striking that charge storage region are prevented from moving to an adjacent charge storage region. The photosensor also includes a plurality of transfer gates, having a gate region adjacent to a corresponding one of the charge storage regions and disposed between that charge storage region and a drain region. The charge collection regions and the drain regions are doped such that the mobile charges collected in the charge storage region will flow to the drain region when a first electric field is applied to the gate region. | 09-17-2009 |
20100002115 | Method for Fabricating Large Photo-Diode Arrays - A photodetector array and method for making the same are disclosed. The photodetector array includes a two-dimensional array of pixels and a controller. Each pixel includes a photodetector and a readout circuit, the readout circuit coupling that pixel to a corresponding bit line when a readout signal is received on a corresponding row line. The controller generates the row selection commands and processes signals on the bit lines. The photodetector array is divided into a plurality of sub-chips fabricated on a semiconductor substrate and having a plurality of metal conductors overlying the substrate. The sub-chips include a plurality of slave sub-chips, each slave sub-chip includes a row decode circuit, and a plurality of the rows of pixels, the row decode circuit in one of the slave-sub-chips providing the readout signals on row lines in that sub-chip in response to one of the row selection commands. | 01-07-2010 |
20100141817 | Imaging Array with Built-in Exposure Control - An imaging array and method for using the same to capture an image are disclosed. The imaging array includes an array of pixel sensors and a controller. Each pixel sensor includes a dual-ported photodiode characterized by ports having first and second gates, and a charge conversion circuit. The charge conversion circuit generates a signal that is a function of a charge on the dual-ported photodiode when the first gate in the dual-ported photodiode is activated to transfer a charge on the dual-ported photodiode to the charge conversion circuit. The controller applies a potential to the second gates and measures a current flowing out of the second gates, each second port passing charge stored in the photodiode connected to the second port when a potential in the photodiode exceeds the applied potential. The controller determines an average light intensity incident on the array of pixel sensors. | 06-10-2010 |
20100141819 | Imaging Array with Non-Linear Light Response - An imaging array and method for capturing an image utilizing the same are disclosed. The imaging array includes an array of pixel sensors in which each pixel includes a dual-ported photodiode or photogate and a charge conversion circuit. The charge conversion circuit generates a voltage signal that is a function of a charge on the dual-ported photodiode. The controller applies a potential that varies over the exposure to the second gates in the dual-ported photodiodes, each second port passing charge stored in the photodiode connected to the second port when a potential in the photodiode exceeds the applied potential. The potential is chosen such that charge flows through the second gates of pixel sensors that are exposed to light intensities greater than a first threshold intensity during the exposure. | 06-10-2010 |
20120075514 | Hybrid Camera Sensor for Night Vision and Day Color Vision - A hybrid imaging array and method for using the same is disclosed. The image array includes a low-light imaging array and a color imaging array. The two imaging arrays can be utilized separately or in conjunction with one another. The low-light imaging array is optimized for night vision or situations in which the light levels are too low to allow a conventional color image to be formed by the color imaging array. The color imaging array is optimized for daylight or color photography. The low-light imaging array can be utilized in conjunction with the color imaging array to provide a color image with reduced noise. | 03-29-2012 |
20130258153 | Hybrid CCD-CMOS Camera Adapted for Forming Images of Moving Scenes - A camera adapted for taking pictures of a moving scene is disclosed. The camera includes an imaging array, a plurality of charge-coupled device (CCD) shift registers, and a controller. The imaging array includes a plurality of CMOS pixel sensors organized as a plurality of columns and rows. The image moves in the column direction. One CCD shift register corresponds to each of the columns. Each CMOS pixel sensor includes a first transfer gate that transfers charge accumulated in the pixel sensor to a corresponding cell in the CCD shift register. The controller controls the CCD shift registers such that charge stored in a first cell in a CCD shift register is moved to a second cell in the CCD shift register where the charge is combined with charge accumulated by the pixel sensor that is connected to the second cell, the combined charge being generated from the same image pixel. | 10-03-2013 |
20130299674 | Digital Pixel Sensor with Reduced Noise - An apparatus and method for forming a digital image are disclosed. The apparatus includes a plurality of pixel sensors and a controller. Each sensor includes a photodiode, a floating diffusion node that can be selectively connected to said photodiode or a reset voltage, and an analog-to-digital converter (ADC) connected to the floating diffusion node, the ADC converting a voltage on the floating diffusion node to a digital value. Each pixel sensor also includes an output circuit that connects the ADC to a bus. The apparatus also includes a controller that causes the ADCs to operate in parallel to convert the voltages on the floating diffusion nodes to the digital values in a time that is less than the time needed for the floating diffusion node to acquire ten electron equivalents of noise. The optional apparatus includes circuitry that allows correlated double sampling to be performed in each sensor. | 11-14-2013 |
20140333808 | Customizable Image Acquisition Sensor and Processing System - An image sensor that includes a first imaging array and a FPGA processor that processes images captured by the imaging array to provide information about the scene projected on the first imaging array is disclosed. The FPGA processor is connected to the first imaging array and includes an interface for receiving images from the first imaging array and an interface to an image storage memory that stores a plurality of images. The FPGA implements a plurality of image processing functions in the gates of the FPGA. The image processing functions processing one of the images stored in the image storage memory to extract a quantity related to the one of the images. The FPGA also includes an I/O interface used by the FPGA to output the quantity to a device external to the image sensor. | 11-13-2014 |
20150076321 | Amplifier Adapted for CMOS Imaging Sensors - A column readout amplifier and imaging an | 03-19-2015 |