Method and system for operating an image data collection device
View Patent ↗In accordance with an exemplary embodiment of the present invention, a method is provided to form an image using an active pixel sensor imager ( 108 ). The method includes placing an active pixel sensor ( 202 ) in electrical contact with a column readout line ( 204 ), lacing a sample-and-hold capacitor into electrical contact with the column readout line, and placing the sample-and-hold capacitor ( 314 or 320 ) in electrical contact with an input capacitor ( 324 or 334 ) on an amplifier ( 222 ). All of the input capacitor ( 324 or 334 ), the sample-and-hold capacitor ( 314 or 320 ), and the active pixel sensor ( 202 ) are in electrical contact for an overlapping period of time. A differential output ( 228 ) from the amplifier ( 222 ) is digitized, and used to form an image.
1. A method of forming an image using an active pixel sensor imager, comprising:
placing an active pixel sensor in electrical contact with a column readout line;
placing a sample-and-hold capacitor into electrical contact with the column readout line;
placing the sample-and-hold capacitor in electrical contact with an input capacitor coupled between the sample-and-hold capacitor and an amplifier, wherein the input capacitor, the sample-and- hold capacitor, and the active pixel sensor are all in electrical contact for an overlapping period of time, and wherein the active pixel sensor charges the sample-and-hold capacitor and the input capacitor during the overlapping period of time;
disconnecting the sample-and-hold capacitor from the amplifier;
digitizing a differential output from the amplifier; and
forming an image from the digitized output.
2. The method of claim 1 , wherein the overlapping period of time is greater than 500 ns.
3. The method of claim 1 , wherein placing the active pixel sensor in electrical contact with the column readout line comprises activating a CMOS FET that is operatively coupled between the active pixel sensor and the column readout line, allowing current to flow between the active pixel sensor and the column readout line.
4. The method of claim 1 , further comprising displaying the image on a display incorporated into an image collection device.
5. The method of claim 1 , further comprising transferring the image to an external device through a network interface controller.
6. An image collection system, comprising:
an optical system configured to focus an image on a detector;
the detector configured to convert the image into image data;
a memory configured to store the image data for processing;
a processor configured to perform calculations on the stored image data;
a second memory comprising machine readable instructions configured to direct the processor to:
place an active pixel sensor in electrical contact with a column readout line;
place a sample-and-hold capacitor into electrical contact with the column readout line;
place the sample-and-hold capacitor in electrical contact with an input capacitor coupled between the sample-and-hold capacitor and an amplifier, wherein the input capacitor, the sample-and-hold capacitor, and the active pixel sensor are in electrical contact for an overlapping period of time, and wherein the active pixel sensor charges the sample-and-hold capacitor and the input capacitor during the overlapping period of time;
disconnect the sample-and-hold capacitor from the amplifier;
digitize a differential output from the amplifier; and
form an image from the digitized output.
7. The image collection system according to claim 6 , wherein the detector comprises an active pixel sensor imager.
8. The image collection system according to claim 6 , comprising a network interface controller configured to transfer images to an external device.
9. The image collection system according to claim 6 , comprising a digital image storage device.
10. The image collection system according to claim 9 , wherein the digital image storage device comprises a disk drive, a recordable optical disk, a digital tape, or any combinations thereof.