Charge coupled detector

Diode Array and Charge-Coupled Detector Systems... 

Figure 1. Time-resolved X-ray diffraction experiment (schematic). The liquid sample is excited by a laser pulse, and its temporal evolution is monitored by a time-delayed X-ray pulse. The diffracted radiation is measured by a charge-coupled detector (CCD). In practice, the laser and X-ray beams are not perpendicular to each other, but nearly parallel.

The availability of solid-state detectors (such as the charge-coupled detector, CCD) makes it possible to acquire simultaneously significant portions of the spectra or even the entire rich spectra obtained by ICP-OES in the UV-Vis region, thus providing a large amount of data. The commercial availability of ICP-OES instruments with these multichannel detectors has significantly renewed interest in this technique. However, some limitations, such as the degradation of the spectral resolution compared with photomultiplier-based dispersive systems, still remain. 

S. Euan, H. Pang and R. S. Houk, Application of generalized standard additions method to inductively coupled plasma atomic emission spectroscopy with an echelle spectrometer and segmented-array charge-coupled detectors, Spectrochim. Acta, Part B, 50(8), 1995, 791-801. 

In certain applications (e.g., X-ray photoelectron spectrometry) an electron beam must be analyzed by its kinetic energy using a 180° hemispherical energy analyzer consisting of two concentric hemispheres coupled to a wide-area charge-coupled detector (see Fig. 10.29). 

If possible, make more accurate measurements of the wavelengths using a high-resolution grating spectrometer as indicated in Fig. 2. The instructor will advise on the most appropriate measurement procedure for the particular setup employed. The spectrometer should have 0.1-nm resolution, or better if possible, and should be equipped with a photomultiplier or charge-coupled detector (CCD). An instrument used for Raman or fluorescence measurements would be quite suitable. 

As with spectrophometric instruments, a number of devices are used as photodetectors in fluorometric instruments, including the photomultiplier tube (PMT) and charged-coupled detector (CCD). In addition, visual observation is used for some applications. 

Advances in design of ICP-AES instruments have led to systems that now incorporate an Echelle grating and a charged-couple detector as shown in Fig. 4.72 (110). A comparison of the major instrumental components for an ICP-AES for instruments manufactured in the 1980s versus those made in... 

During the last two decades, there has been an enormous increase in the use of photophysical methods in supra-molecular chemistry. Until recently, photophysical methods, such as transient spectrometry and time-resolved fluorescence spectrometry, were primarily research tools in the arenas of photokinetics of small molecules, materials physics, and biophysics. This situation changed dramatically with the introduction of commercial, user-friendly electro-optical components such as charge-coupled detector (ED)-based spectrometers, solid-state pulsed lasers, and other instrumentation necessary for time-resolved measurements. As a result, time-resolved spectrometry became more available to the community of supramolecular chemists, who now reached the level of sophistication that can benefit from the new horizons offered. 

Charge coupled detectors These devices are not yet commonly available in commercial instrumentation for analytical spectrophotometry although they are used in applications in inductively coupled plasma atomic emission spectrometry. However, they have found extensive application in imaging and astronomical applications. Essentially they are two-dimensional photodiode arrays which allow many spectra to be acquired in one readout. A typical array sensor is shown in Figure 9. 

CCD Chemical composition distribution (or charge-coupled detector)... 

The NanoPhotometer Pearl (from Implen, GmbH www.implen.com) is a compact dual-channel Czerny Turner grating spectrometer with a 1024 pixel charge-coupled detector (CCD) array detector and xenon flash lamp source (Figure 5.30). 

Conventional X-ray diffraction method cannot distinguish polymorphs which have relatively small crystallites because of the low resolution of diffractometers. Synchrotron sources have been employed to obtain high-resolution electron diffraction patterns which enable differentiation of such polymorphs (18). The development of very sensitive charge-coupled detectors (CCD) has allowed electron diffraction patterns to be recorded in a few seconds using very low electron currents. 

A CCD (charge coupled detector) type space filter, shown in Fig. 23, was used by Fiedler et al. (1997) to measure sand particle velocity in a CFB riser. The authors were able to measure the velocities between 0.12 and 40 m/s, at local solid volume concentration 0.1-4%. They reported that particles finer than 5/xm... 

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