MONOCHROMATOR AND SPECTROPHOTOMETER

摘要

A monochromator (20) for use in a spectrophotometer, and a spectrophotometer, in which the provision of substantially monochromatic light for absorption or fluorescence measurements is provided by a dispersive means of the monochromator (for example a diffraction grating (34) or prism), or by an alternative wavelength selecting element such as an optical bandpass filter of the spectrophotometer, without altering the geometry of the optical path. This is enabled by the dispersive means (34) of the monochromator (20) being associated with (for example by back-to-back mounting) a non-dispersive means such as a plane mirror (36) whereby the non-dispersive means (36) is positionable in place of the dispersive means (34) by, for example, a rotational drive means (40-38). This allows for light (46) entering the monochromator (20) through entrance slit (22) to be transmitted therethrough to exit slit (32) without dispersion and without altering the geometry of the optical path. The choice of use of different dispersion means of a spectrophotometer without altering the optical path allows for optimation of the spectrophotometer for a wide range of analytical applications.