Charge transfer through CCD shift registers occurs after integration to relocate accumulated charge information to the sense amplifier, which is physically separated from the parallel pixel array. This tutorial explores several clocking schemes that are utilized to transfer charge from the collection gates to the output node.

The applet initializes with a deactivated four-phase clocking scheme loaded into the window. Start the applet by selecting the Auto button, which will run the charge transfer automatically. Electrons comprising the integrated charge are represented by a green pool that is transferred through energy minima from one gate to the next. To step through the sequence manually, either click the Manual button to halt automatic transfer, or click on the Next >> button. Each click on the button will advance the tutorial a single step. Use the radio buttons to toggle between two-, three- and four-phase CCD clocking schemes.

The charge transfer process is termed readout, and is controlled by a series of clocks that operate on all gates in the array, including the transfer gate between serial and parallel registers and the photodiode reset gates. This cascade of clocking schemes is used to operate the CCD in a controlled and efficient manner.

---

BACK TO DIGITAL IMAGING IN OPTICAL MICROSCOPY

Questions or comments? Send us an email.

© 1998-2022 by Michael W. Davidson and The Florida State University. All Rights Reserved. No images, graphics, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.

This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.

Last modification: Thursday, Feb 11, 2016 at 09:49 AM

Access Count Since July 1, 2000: 48883

Visit the websites of our partners in digital imaging education: