Gary R. Sims

Electro-Optical Characterization Of The Tektronix TK512M-011 Charge-Coupled Device

The electro-optical characterization of the first in a new series of Tektronix CCDs is described. This device, the TK512M-011, is a frontside-illuminated CCD with a 512 by 512 format and 27 by 27 um pixels. Electro-optical characteristics measured in this study include linearity, blooming, dark count rate, charge-transfer efficiency (CTE), and quantum efficiency. The results of a detailed study of the noise characteristics of the CCD output FET are reported. The TK512M-011 has excellent photometric lin-earity, high well capacity, and a low dark count rate. Very good low light level CTE is observed in the parallel shift direction; however, CTE problems are observed in the serial direction. The quantum efficiency of the front-side-illuminated CCD over the wavelength range of 400 to 1000 nm is lower than expected based on experience with similar devices. The noise of the output FET of the CCD is equivalent to 5 to 12 electrons, depending on the FET operating conditions and system bandwidth. A very small latent image effect is noted. The conclusion of this evaluation is that despite the problems observed, the frontside-illuminated Tektronix CCD is an excellent sensor for scientific imaging applications.

The Effect of Charge Traps on Raman Spectroscopy Using a Thomson-CSF Charge Coupled Device Detector

Charge coupled device (CCD) detectors have seen increasing use in analytical spectroscopy in recent years. These detectors are optical array detectors based on silicon-metal oxide semiconductor technology. The basis of operation, the characteristics, and the modes of operation in a variety of analytical spectroscopies have recently been discussed in several excellent reviews by Denton and co-workers.

Crossed interferometric dispersive spectroscopy

A novel design is described which combines dispersive and interferometric spectrometric instrumentation for ultraviolet visible spectroscopy, offering significant advantages in comparison to conventional spectroscopic configurations. The optical system incorporates the triangular common-path interferometer with an additional cross-dispersive element, allowing spectra to be obtained in a format compatible with rectangular CTD array detectors. The use of a cross-dispersive optical element reduces the distributive multiplex effects of interferometry in a rugged, compact, optically simple system.

Characterization Of A Charge-Injection-Device Camera System As A Multichannel Spectroscopic Detector

A solid-state camera system designed for use as a multichannel detection system for spectroscopic applications is evaluated. The camera is based on a charge-injection-device sensor that permits very high dynamic range operation by virtue of its unique nondestructive readout capability. Methods of determining gain and readout noise are discussed. Performance of the camera system is evaluated with respect to sensitivity, linearity, readout noise, and dynamic range. The use of nondestructive readout to reduce effective readout noise and increase dynamic range is described. Spectral responses in the visible and ultraviolet of coronene-coated and uncoated devices are reported. Various time-dependent anomalies caused by interface trapped charge are discussed.

Charge-coupled device signal processing models and comparisons

CCD signal processing schemes attempt to reduce the effect of (KTC), 1/f, and broadband noise on the output signal. A number of schemes have been reported over the years. These schemes employ time delay and subtraction to eliminate KTC noise and attenuate 1/f noise. They also include a low-pass function to reduce the effect of broadband noise. Signal processing schemes include dual-slope integration, correlated-double sampling, a variation of correlated-double sampling referred to as switchedexponential filtering, and transversal filters. Signal processing that does not use delay and subtraction to eliminate KTC noise is also discussed. A consistent technique is used to analyze the various processing schemes. Transfer functions for signal and noise are presented for each. Performance comparisons are given with emphasis on their applicability to relatively high speed CCD readout applications (readout rates of 1 Mpixel/s and faster).

Single-Element Charge-Injection Device As A Spectroscopic Detector

The need for a single-element charge-transfer device as a spectroscopic detector is discussed. Such a detector promises to offer superior performance compared to current photomultiplier tubes over a wide range of illumination levels. As a detector to address this need, the prototype CID75 manufactured by General Electric Co. is described and characterized. The CID75 is a single-element charge-injection-device sensor with a 1 mm by 1 mm photoactive area and a readout rate adjustable from 0 to 20 kHz. The electro-optical characteristics reported in this study include linearity, read noise, full-well capacity, dark count rate, and quantum efficiency. The sensors have good photometric linearity with a full-well capacity in excess of 1.2 x 108 e -. The read noise of the detector can be lowered to 80 e - when its nondestructive readout mode is employed. The quantum efficiency of the CID75 is reported for the wavelength range from 200 to 1000 nm. Combining a simple dynamic range of 106 with the ability to vary integration times over four orders of magnitude allows this detector to quantify photon fluxes varying over 10 orders of magnitude. The conclusions of this study are that the CID75 sensor is a useful detector for a variety of applications.