Linear photodiode arrays

The classical silicon photodiode linear array manufactured by Reticon was the first detector marketed successfully. Similar solid state linear array detectors based on charge coupled devices, or charge.injection devices may also be of interest. Typical of the families of detectors, the Reticon detectors are built in a number of elements/array sizes. Commercially available units have anywhere from 128 to 1024 elements/array. Each individual element in the array is 1 x 1 mil to 1 x 100 mil in area, and are spaced on approximately 1 mil centers. The spectrometer system discussed in this article was built using Reticon-type devices. 

Photodiode array A linear array of photodiodes that can detect multiple wavelengths simultaneously see diode array detector. Photoelectric colorimeter A photometer that responds to visible radiation. 

Fig. 6.14. Schematic representation of the array of linearly coupled lasers. PDl and PD2 are the photodiodes, which detect the output from the outer lasers.

Antcliff, R. R., Hillard, M. E., and Jarrett, O. "Intensified Silicon Photodiode Array Detector Linearity Application to Coherent Anti-Stokes Raman Spectroscopy." Applied Optics 14 (1984) 2369. 

Photodiode arrays Basically, these arrays are made up of silicon photodiodes linearly set up within an integrated circuit. The numbers in each array are typically 512 or 1024. The photocurrent from each diode causes a capacitance build-up proportional to the incident light flux, which is read by sequentially discharging the array elements via an analog-to-digital converter for data processing. These arrays have a spectral response similar to that of the silicon photodiode, i.e., 180-1100 nm. A typical sensitivity plot is shown in Figure 8. 

FIGURE 16. SERS spectrum of pyridine in the 950- to 1050-cm region as a function of potential in three pH regions. Recorded with a Spex Triplemate spectrometer, an intensified photodiode linear array detector, and a Tracor Northern optical multichannel analyzer (OMA). 

A linear array of photodiodes providing the ability to detect simultaneously radiation at several wavelengths. 

Sihcon charge coupled devices (CCDs), commonly used in soHd-state video cameras and in research appHcations, are being appHed to low light level spectroscopy appHcations. The main advantage of area array CCDs over linear photodiode detectors is the two-dimensional format, which provides simultaneous measurements of spatial and spectral data. 

Active matrix addressing can also be used in printer heads [628] and linear sensor arrays [629]. a-Si H TFTs are used to address a linear array of output or input transducers, respectively. In the linear sensor array, u-Si H photodiodes are used. 

Gong, Y. and Yeung, E.S., An absorption detection approach for multiplexed capillary electrophoresis using a linear photodiode array, Anal. Chem. 71,4989, 1999. 

Linear phosphonitrilic chlorides (LPNCs), silicone fluids and, 22 573 Linear photodiode arrays, 19 153 Linear polyesters, 14 116 Linear polyethylene fibers, 20 398 Linear polyimides, synthesis of, 20 273 Linear polymers, 20 391 25 455 high molecular weight, 23 733 zero-shear viscosity of, 19 839 Linear poly(thioarylene)s, 23 705 Linear PPS, 23 704. See also... 

Micellar electrokinetic capillary chromatography with photodiode array detection was used for the determination of polyaromatic hydrocarbons in soil [65]. A detection limit of lOpg and linear calibration over five orders were observed. Compared to a standard gas chromatographic analysis method, the miscellar electrokinetic chromatographic method is faster, has a higher mass sensitivity and requires smaller sample sizes. 

A diode array is a series of several hundred photodiodes arranged in a linear array. Single-beam spectrophotometers have been invented that utilize a diode array as the detector. In this case, the cuvette is positioned between the source and the dispersing element. Then, following the dispersion of the fight, there is no exit slit. The spray of wavelengths created by the grating fall instead across the diode array,... 

The use of a linear detector array in the image plane of a polychromator in place of the fluorescence monochromator in Figure 12.1 enables the parallel data accumulation of complete fluorescence spectra. Silicon photodiode arrays, operated in a CCD mode(34) are the most widely used detector elements. The spectral response of the diodes enables fluorescence to be detected from the near-UV up to ca. 1100 nm with a peak response in the near-IR. Up to 8192 elements are now available commercially in a single linear array at low cost. However, the small length of each element (ca. 10 [im) presently limits sensitivity and hence cylindrical lens demagnification is often necessary. 

Detectors are used to convert X-ray flux into an electrical signal, which can then be digitized and stored. For imaging cabinet X-ray systems, the detectors usually consist of a folded linear array of scintillators optically coupled to photodiodes. Typically, 500-1000 such detector elements are present for single-energy imaging... 

A PMT mounted at right angles to the incident laser beam permits continuous recording of the light scattered at that angle. In addition, a 512-element linear photodiode array (not shown) is mounted on the ring electrode... 

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