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Morris, M. B.

Publications and source records attributed to Morris, M. B..

Fizeau wavemeter for pulsed laser wavelength measurement

A Fizeau wavelength meter optimized for use with pulsed laser sources has been developed and characterized which demonstrates a CW resolution better than 2 parts in 10 to the 7th and a pulsed resolution better than 1 part in 10 to the 6th. The static optical design is based on a Fizeau wedge interferometer, which together with spatial filtering and collimating optics is used to produce a pattern of parallel fringes which is imaged on a linear photodiode array and analyzed by a minicomputer. A series of CW and pulsed measurements of various narrowband laser sources are described, and particular difficulties involved in pulsed laser measurements with the wavemeter are examined.

Morris, M. B.↗

Portable high-resolution laser monochromator-interferometer with multichannel electronic readout

A high-resolution 0.4-m monochromator is described for use in wavelength diagnosis of tunable pulsed and CW laser sources in the 3000-10,000-A region. The f/20 design uses an echelle grating in an over-and-under Ebert configuration with a scanned photodiode array to provide a real-time multichannel display of spectral output. Absolute wavelength may be determined to 0.1 A with the monochromator, and a Fabry-Perot interferometer attachment extends linewidth measurement capability to 0.01 A or better. Spectra are displayed on a storage oscilloscope, and calculation of laser parameters is explained. The instrument measures 70 cm long x 15 cm wide x 20 cm high.

Morris, M. B.↗