Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
active pixel sensor (APS)
Post: #1

active pixel sensor (APS)

An active pixel sensor (APS) is an image sensor consisting of an integrated circuit containing an array of pixels, each containing a photodetector as well as three or more transistors. Since it can be produced by an ordinary CMOS process, APS is emerging as an inexpensive alternative to CCDs.

Pixel: The standard CMOS APS pixel consists of three transistors as well as a photodetector.
The photodetector is usually a photodiode, though photogate detectors are used in some devices and can offer lower noise through the use of correlated double sampling. Light causes an accumulation, or integration of charge on the 'parasitic' capacitance of the photodiode, creating a voltage change related to the incident light.
One transistor, Mrst, acts as a switch to reset the device. When this transistor is turned on, the photodiode is effectively connected to the power supply, VRST, clearing all integrated charge. Since the reset transistor is n-type, the pixel operates in soft reset.

The second transistor, Msf, acts as a buffer (specifically, a source follower), an amplifier which allows the pixel voltage to be observed without removing the accumulated charge. Its power supply, VDD, is typically tied to the power supply of the reset transistor.

The third transistor, Msel, is the row-select transistor. It is a switch that allows a single row of the pixel array to be read by the read-out electronics.

Array: A typical two-dimensional array of pixels is organized into rows and columns. Pixels in a given row share reset lines, so that a whole row is reset at a time. The row select lines of each pixel in a row are tied together as well. The outputs of each pixel in any given column are tied together. Since only one row is selected at a given time, no competition for the output line occurs. Further amplifier circuitry is typically on a column basis.

Important Note..!

If you are not satisfied with above reply ,..Please


So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page
Popular Searches: karmasangsthan bangali news paper aps downlod, lottery sambad pdf aps, aps transmission projects, result aps dagshai 2014, 5 acoustic parking system aps ppt, acoustic parking system aps ppt, active pixel sensor tutorial,

Quick Reply
Type your reply to this message here.

Image Verification
Image Verification
(case insensitive)
Please enter the text within the image on the left in to the text box below. This process is used to prevent automated posts.

Possibly Related Threads...
Thread: Author Replies: Views: Last Post
  wireless sensor networks full report project report tiger 18 14,127 15-07-2013 12:18 PM
Last Post: computer topic
  Low Power Wireless Sensor Network computer science crazy 4 4,530 30-04-2013 10:04 AM
Last Post: computer topic
Photo Smart Pixel Arrays Computer Science Clay 4 1,749 07-02-2013 10:19 AM
Last Post: seminar details
  Seminar on Active Microwave Radar computer girl 1 1,478 03-01-2013 02:38 PM
Last Post: seminar details
  Opportunistic Routing for Wireless Ad Hoc and Sensor Networks: Present and Future seminar presentation 3 2,241 22-11-2012 01:26 PM
Last Post: seminar details
  universal current sensor full report project report tiger 11 9,980 08-11-2012 02:28 PM
Last Post: seminar details
  Seminar on Wireless Sensor Networks is an Intelligent Electronic Devices computer girl 0 722 11-06-2012 04:03 PM
Last Post: computer girl
  Seminar on Wireless Ad hoc Sensor Networks computer girl 0 473 09-06-2012 01:09 PM
Last Post: computer girl
Last Post: computer girl
Music Smart Sensor (Download Full Report And Abstract) computer science crazy 10 6,853 06-03-2012 10:33 AM
Last Post: seminar paper