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UV/Visible Microspectrophotometry

المؤلف:  Max M. Houck، Jay A. Siegel

المصدر:  Fundamentals of Forensic Science

الجزء والصفحة:  103

2026-06-29

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UV/Visible Microspectrophotometry

There are many types of evidentiary materials that are too small to be accommodated by an ultraviolet spectrophotometer. For example, one may wish to determine the exact color of a tiny paint chip and compare it to paint taken from a car suspected of being involved in a hit and run case. This could be accomplished by determining the exact wavelengths of light that are absorbed or reflected by the paint. A tiny paint chip could not be made to fit properly into a conventional spectrophotometer. The solution is to combine a powerful microscope with a UV/visible spectrophotometer. Light that travels through the microscope onto the paint chip is detected by a photocell, just as in a normal spectrophotometer. The ultraviolet and visible spectra are thus obtained and comparisons can be made. Figure 5.8 shows a UV/visible microspectrophotometer.

FIGURE 5.8 A UV/visible microspectrophotometer. The rectangular module on top is the UV/visible spectrophotometer. It sits upon the microscope, which focuses the light onto the sample. It is capable of absorption or reflectance spectroscopy.