Laser
longitudinal mode refers to the axial
distribution of the light field along to
its direction of propagation. An
ordinary laser usually has a few or dozens of longitudinal modes. Using high
resolution spectrometer to test the laser spectrum, there will
be multiple laser frequencies (or wavelengths). If restraining
most of the longitudinal modes through selecting frequencies and
just retaining one of them, then we could get single
longitudinal mode (single frequency) laser.
Single longitudinal laser compares with ordinary
laser, has narrower line width and coherence length. It is
widely used in spectrum analysis, holographic imaging, interferometry and other fields. |
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Testing Instrument: F-P Scanning
Interferometer |
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Model |
FCSI |
Applicable wavelength |
473nm,532nm,1064nm, etc. |
Free
spectrum range |
75GHz (Adjustable) |
Finess |
100 |
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Examples
of Testing Results |
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Single longitudinal mode
testing |
Multiple longitudinal
modes testing |
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