Low-loss charge-coupled device
Abstract
Two closed-loop CCD structures, a 256-stage and a 1024-stage devices were designed, fabricated, and operated to demonstrate a low-loss mode of operation for a very long CCD delay line or a closed-loop CCD structure. The low-loss CCD concept consists of operating a CCD with each signal charge well followed by one or more trailing-bias-charge wells. Two orders of magnitude improvement in the effective transfer losses were demonstrated experimentally by periodically recombining at a signal-regeneration stage the (first-order) signal-charge transfer losses collected by the trailing bias charger with the corresponding signal-charge packets. An effective transfer loss of 2.4 x 10 to the -7th power per transfer was demonstrated. The maximum time delay has also been improved by two orders of magnitude over that of conventional CCDs by means of a new dark-current subtraction technique. The 1024 stage closed-loop low-loss CCD was also operated as a synchronous signal correlator producting an improvement in the signal-to-noise ratio of 17.5 dB as a result of 100 signal recirculations in the loop.
- Publication:
-
Final Technical Report
- Pub Date:
- June 1979
- Bibcode:
- 1979rca..rept.....K
- Keywords:
-
- Charge Coupled Devices;
- Charge Transfer;
- Delay Lines;
- Feedback Control;
- Chips (Electronics);
- Circuit Diagrams;
- Methodology;
- Signal To Noise Ratios;
- Tests;
- Electronics and Electrical Engineering