Research to define algorithms appropriate to a high-data-rate laser-wavelength-measurement instrument
Progress made over a four year period on a computer controlled laser wavelength meter is summarized. The optical system of the laser wavelength meter consists of a series of Fabry-Perot interferometers and one high resolution confocal interferometer, preceeded by a one-half meter grating spectrometer. The interferometrically generated fringes are imaged on linear diode arrays, read into computer memory and processed by an efficient, noise resistant, algorithm which calculates the wavelength. The algorithm fitting routine generates high accuracy fringe fits at a rate of 5Hz with the present LSI 11/2 processor. A 10 Hz fitting rate is expected with the LSI 11/23 processor. Fringes are fit with an rms error of less than +- 0.01. The wavelength measurement accuracy is thus one hundredth of the free spectral range of the interferometers, which at present are 10 cm/sup -1/, 1 cm/sup -1/, 0.1 cm/sup -1/ and 0.01 cm/sup -1/. Thus wavelengths can be measured to +- .0001 cm/sup -1/ or +- 3 MHz. The wavelength meter interferometers are calibrated by a stabilized HeNe laser source with a long term stability of better than +- 1 MHz. Fringes have been fit for over 10/sup 6/ cycles to demonstrate the stability of the algorithm. When the hardware is transferred from the present bread-borad mounting to final mounting, the wavelength meter will provide an accurate and versatile approach for measuring and displaying cw, pulsed, single mode or multi mode laser spectra.
- Research Organization:
- Lawrence Livermore National Lab., CA (USA)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 5307690
- Report Number(s):
- UCRL-15451; ON: DE82012811
- Resource Relation:
- Other Information: Portions of document are illegible
- Country of Publication:
- United States
- Language:
- English
Similar Records
Trace detection in gases using photoacoustic spectroscopy and Fabry-Perot interferometry
Jet-cooled infrared spectra and investigation of the Torsion-rotation energy levels of methanol in the C-H stretch region
Related Subjects
INTERFEROMETERS
ALGORITHMS
DESIGN
LASER RADIATION
WAVELENGTHS
ACCURACY
CALIBRATION
COMPARATIVE EVALUATIONS
DATA ACQUISITION
DATA PROCESSING
FABRY-PEROT INTERFEROMETER
GRATINGS
HELIUM-NEON LASERS
IMAGES
MICROPROCESSORS
PERFORMANCE TESTING
SPECTROMETERS
STABILITY
COMPUTERS
ELECTROMAGNETIC RADIATION
ELECTRONIC CIRCUITS
GAS LASERS
LASERS
MATHEMATICAL LOGIC
MEASURING INSTRUMENTS
MICROELECTRONIC CIRCUITS
PROCESSING
RADIATIONS
TESTING
440300* - Miscellaneous Instruments- (-1989)