摘要 |
A spectrophotometer measures optical absorption of light by a sample received in a sample cell. An array of optical elements disperses the light over a spectral pattern, and a fiber optic beam splitter splits light at a selected spectral band into a reference component and a test component. Detectors measure the intensity of the reference component and the test component after the test component passes through the sample. The fiber optic beam splitter includes a plurality of strands arranged with first ends terminating in a common circular area. Opposite ends of peripheral strands are collected into a first set that transmits the test component while the remaining strands for a second set that transmits the reference component. Preferably, there is a single, central, large strand surrounded by smaller strands. Two emitters are provided for light of two different types, such as visible and UV. The optical array forms a collimated beam having an inner core of one type of light and an outer shell of the other. Specially constructed optical elements then reflect and refract the collimated beam. A motor drives a mirror to scan the beam across an optical slit positioned in front of the beam splitter to select a desired spectral band.
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