The detector is usually placed perpendicular to the path of the incident radiation in order to eliminate the possibility of monitoring the incident radiation.
Another category of spectral analysis in which the incident radiation changes direction is refractometry.
Polished metal surfaces, on the other hand, absorb only about 6 percent of the incident radiation, reflecting the rest.
Normally absorptiometry is subdivided into categories depending on the energy or wavelength region of the incident radiation.
Placing the detector out of the path of the incident radiation eliminates the possibility of measuring its intensity.
If the incident radiation is ultraviolet radiation, the method is termed ultraviolet photoelectron spectroscopy (UPS) or photoelectron spectroscopy (PES).
Sensitive to X rays, gamma rays, and charged particles, scintillation counters permit high-speed counting of particles and measurement of the energy of incident radiation.
The analyte is placed in the cell, and the wavelength of the incident radiation is scanned throughout a spectral region while the absorption is measured.
Raman and Rayleigh scattering occur when the dimensions of the scattering particles are less than 5 percent of the wavelength of the incident radiation.
The resulting plot of radiative intensity or absorption as a function of wavelength or energy of the incident radiation is a spectrum.
In both Tyndall scattering and Rayleigh scattering, the wavelength of the scattered radiation is identical to that of the incident radiation.
