Line rejection

Plot peak height vs. /xg/ml of metal added, plot the least-squares line, and plot on either side of the least squares fine two lines which represent two standard deviations from the least squares line. Reject any peak heights that lie outside the acceptable limits. 

The essence of acceptable assembly quality is to eliminate production line rejects and failures over the life of the manufactured product. Aerobic acrylic activator curing... 

An efficient mechanism for rejection of the scattered laser-line radiation has to be incorporated. The major new development in this area is the introduction of holographic filters. These devices have the sharp cut-off characteristics of the multilayer dielectrics, but do not exhibit a harmonic structure in the transmission curve. The transmission is high (80-90%) and featureless, as opposed to the dielectrics which have numerous features in the transmission curve because of interference among the multiple layers. Two filters are sufficient to give Rayleigh-line rejection, and spectral information down to 150 cm" can be obtained. Another filter type is the Chevron unit [41] which has been shown by Nicolet, and possibly Bruker, to give Raman data down to 60 cm. Additionally, data can be obtained on both the Stokes and anti-Stokes bands [42]. 

Single element laser line rejection filters reject more of the low-frequency Raman spectrum, but... 

A Raman monochromator can be a diffraction grating instrument, two or three diffraction grating instruments in series (double or triple monochromator), or a single element bandpass filter. A triple monochromator is an extremely flexible instrument, but it is very complex and it uses Raman photons very inefficiently. All Raman photons outside the monochromator pass-band are lost. The first two monochromators serve as an excellent laser line rejection filter, though. 

MM Carrabba, KM Spencer, C Rich, D Rauh. The utilization of a holographic bragg diffraction filter for Rayleigh line rejection in Raman spectroscopy. Appl Spectrosc 44 1558-1561, 1990. 

A Schulte. Near-infrared Raman spectroscopy using CCD detection and a semi-conductor bandgap filter for Rayleigh line rejection. Appl Spectrosc 46 891-893, 1992. 

MJ Pelletier. Potassium vapor near-IR laser line rejection filter for Raman spectroscopy. Appl Spectrosc 47 69-74, 1993. 

GJ Puppels, CG deGrauw, MBJ tePlate, J Greve. Chevron-type dielectric filter set for efficient narrow-band laser line rejection in Raman microspectrometers. Appl Spectrosc 48 1399-1402, 1994. 

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