Abstract: A fluorescence spectrophotometer in which a monochromatic beam of radiation is directed from an excitation monochromator through a first optical system to a sample being evaluated. Fluorescence from the sample is collected by a second optical system and is directed to an emission monochromator. These optical systems are arranged such that slit images from the respective monochromators lie in a single plane defined by the intersecting axial rays of the excitation and fluorescence beams. In several advantageous arrangements the optical system includes aspherical mirrors arranged to give different magnifications of the images in the horizontal and vertical planes. The intensity of the excitation beam applied to the sample and of the output signal may be further increased by positioning wedge shaped optical elements adjacent the sample.

Abstract: 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.degree. 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.

Abstract: 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.degree. 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.