Charge-coupled device , image development

The main detectors used in AES today are photomultiplier tubes (PMTs), photodiode arrays (PDAs), charge-coupled devices (CCDs), and vidicons, image dissectors, and charge-injection detectors (CIDs). An innovative CCD detector for AES has been described [147]. New developments are the array detector AES. With modem multichannel echelle spectral analysers it is possible to analyse any luminous event (flash, spark, laser-induced plasma, discharge) instantly. Considering the complexity of emission spectra, the importance of spectral resolution cannot be overemphasised. Table 8.25 shows some typical spectral emission lines of some common elements. Atomic plasma emission sources can act as chromatographic detectors, e.g. GC-AED (see Chapter 4). 

P. G. LeComber and W. E. Spear, The Development of the a-Si H Field-Effect Transistor and Its Possible Applications D. G. Ast, a-Si H FET-Addressed LCD Panel S. Kaneko, Solid-State Image Sensor M. Matsumura, Charge-Coupled Devices M. A. Bosch, Optical Recording A. D Amico and G. Fortmato, Ambient Sensors H. Kukimoto, Amorphous Light-Emitting Devices R. J. Phelan, Jr., Fast Detectors and Modulators J. I. Pankove, Hybrid Structures... 

Recently, an automatic color video image analysis system was developed to quantify antigen expression (androgen receptor) (Kim et al.,T999a). This system provides a linear relationship between the antigen content and mean optical density of the immunoperoxidase-substrate reaction product. Titration of antibody, concentration, and reaction duration of the substrate can be optimized with this system. The imaging hardware consists of a Zeiss microscope, a three-chip charge-coupled-device camera, a camera control board, and a Pentium-based personal computer. 

The first detectors to be used in OMA systems were standard TV image tubes. These were silicon vidicons or the more sensitive Silicon Intensified Target (SIT) detectors, which both employed silicon targets to convert optical information into electronic form. More recently, the use of solid state detectors in the form of a diode array (Reticon) has been found to have some advantages over the vidicons and SIT tubes. Current developments in the field of charge coupled devices (CCD) will probably soon provide an even better multielement detector for use in OMA systems. 

The multiwire devices, though workhorses for about 10 years, were an intermediate in the development of the detectors we use today. They provided excellent data, but even faster, more reliable, more accurate devices became available in the late 1980s. The instruments that we use today fall into two categories those based on what are called image plates, and those based on charge coupled devices (CCD) detectors. While CCD detectors are now exclusively used at synchrotrons because of their almost instantaneous readout of data, necessary with high intensity sources with short exposure times, most university and private laboratories continue to use detectors based on image plates. 

We developed two kinds of multidimensional fluorescence spectroscopic systems the time-gated excitation-emission matrix spectroscopic system and the time- and spectrally resolved fluorescence microscopic system. The former acquires the fluorescence intensities as a function of excitation wavelength (Ex), emission wavelength (Em), and delay time (x) after impulsive photoexcitation, while the latter acquires the fluorescence intensities as a function of Em, x, and spatial localization (%-, y-positions). In both methods, efficient acquisition of a whole data set is achieved based on line illumination by the laser beam and detection of the fluorescence image by a 2D image sensor, that is, a charge-coupled device (CCD) camera. 

A wide variety of solid-state detectors consisting of multiple elements (multiple channels) have been developed over the past 20 years (140). Devices that fall into this category include silicon photodiode (SPD) arrays, charge injection devices (CID), charge coupled devices (CCD), microchannel plate (MCP) image inten-... 

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