摘要 |
<p>Dual beam Fourier-type spectrometer incorporating distinct sample (11) and reference (13) beams which enter the Michelson-type interferometer on the same side of the beamsplitter (17) and propagate at slightly different angles through the interferometer. The portions of both beams which emerge from the side of the beamsplitter (17) opposite the input side are directed to two separate optical detectors (33 and 35) the outputs of which are electronically subtracted. In a preferred embodiment, the interferometer is of the refractively scanned type, wherein the increased field-of-view facilitates the use of beams having different propagation angles. </p> |