A Rapid-Scan Spectrometer for Scanning 2000 A-15 microm in 3 sec.

A spectrometer has been built which scans from 2000 A 15 micro in 3 sec, and which scans subdivisions to of that range up to 160 times/sec. Four plane reflectance gratings and six detectors are used to cover the range. The first-order spectrum of each grating is scanned by sweeping a sequence of corner mirrors through the intermediate focal plane of a double pass grating monochromator. The four gratings are mounted on a turret, driven by a stepper motor. Between scans, the turret rotates to change gratings,and the appropriate filters and detectors are simultaneously selected automatically. The turret can be stopped and any of the four grating ranges can be scanned 160 times/sec. Absorption spectra and emission spectra of hot samples can be measured alternately. The measured resolution at 3125 A is better than 6 A, and at 3.3 microm better than 0.011 microm.