Feature extraction system for extracting a predetermined feature from a signal

摘要

A fluorescence spectrophotometer in which the optical system for the excitation monochromator includes an arrangement for forming an image of the exit slit of the monochromator adjacent a first surface of the sample being evaluated and for forming an aperture image adjacent a second surface of the sample. Fluorescence from the sample is directed to an emission monochromator which likewise has an arrangement for forming an image of the emission monochromator's entrance slit adjacent a third surface of the sample and for forming an aperture image adjacent a fourth surface. The optical components are arranged such that the images of the slits lie in a single plane defined by the axial rays of the excitation and fluorescence beams, and in several advantageous arrangements the slit images are oriented at 90° from the slits themselves. The intensity of the output signal may be further increased by locating mirrors behind the sample holder to direct the light back through the sample for a second pass. This is a Reissue of a Patent which was the subject of a Reexamination Certificate No. B1 4,022,529, dated May 10, 1977, Request No. 90/000,155.