Spectrophotometry stray light

Stray-light errors are more likely to be observed near the wavelength limits of an instrument, where the radiation intensity of the source and the efficiency of the optical system are reduced, especially below 220 nm and at the crossover point between the ultraviolet and the visible lamps (about 320 to 400 nm). Errors may become serious where the solvent absorbs strongly or where a strongly-absorbing sample is measured by difference spectrophotometry. 

Ultraviolet spectrophotometers cont.), single-beam, 225 standardisation, 226 Ultraviolet spectrophotometry, 221-232 absorption cells, 226 colorimetry, 228 derivative, 230 difference method, 229 dual-wavelength, 229 identification by, 231 influence of pH, 224 influence of solvent, 224 laws of absorption, 222 quantitative applications, 227 stray-light effects, 224 Ultraviolet-visible detector, 202 multiwavelength, 211 Unicontin, 1011 Unidiarea, 474 Unidone, 356 Uniflu, 557, 893 Unilobin, 709 Unimycin, 846 Uniphyllin, 1011 Uniprofen, 677 Unisom, 576... 

Because all the rules that apply to absorbance detection apply equally well to CD, it is convenient to think of CD as a modified form of absorption spectrophotometry. Spectra are temperature- and pH-dependent non-linear correlations of signal versus concentration are commonplace and are produced for the same reasons, such as chemical equilibria, polychromatic radiation, stray light, etc. Fluorescence emission CD (FDCD) spectroscopy is observed whenever an analyte meets all... 

Analogously to spectrophotometry, stray radiation can alter the measured turbidance (Eq. 4.6), the limitation becoming more severe at lower transmitted power. The presence of suspended matter in the processed sample is inherent to turbidimetry and leads to an amplification of stray light due to scattering effects. This effect has not been systematically investigated in flow analysis. 

Slavin W (1963) Stray Light in Ultraviolet, Visible, and Near-infrared Spectrophotometry. Analytical Chemistry 35(4) 561-566. 

Gibson states that it can be a source of important error in spectrophotometry and lists some of the causes of stray light ... 

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