Divergence Measurement
DataRay offers a full range of ISO 11146-compliant beam profilers, both camera- and scanning slit-based which provide multiple methods of measuring beam divergence.
Beam divergence is defined in the far-field where the beam divergence is constant. For highly diverging beams the divergence measurement can be made directly in the far-field, but for lower divergence or collimated beams the beam waist and far-field may be inaccessible or difficult to define.
When measuring far-field divergence from the:
- Far-Field (greater than four Rayleigh ranges from the waist)
- Use a BeamMap2 (with appropriate plane spacing) in divergence mode to measure divergence directly in real-time for beam divergences between 1 & 350 mrad (0.02° to 20°). Good for CW and very high rep rate pulsed lasers.
- Use a single plane Beam Profiling Camera or Scanning Slit Beam Profiler on a linear stage to measure the beam diameter along several Z-positions to measure divergence directly.
- Use a single plane Beam Profiling Camera or Scanning Slit Beam Profiler to measure beam diameter at a known distance Z from the source to measure divergence directly with the assumption of a point source.
- Near Field and Far Field – Use a BeamMap2 in M² mode with the beam waist at the zero plane. The first three planes are in the near-field and the last is in the far-field. This provides real-time M2 and divergence measurements.
- Near Field, Far Field or Unknown – See Gaussian Beam Divergence Measurement application note and its associated Excel worksheet. Use with an ancillary lens and appropriate Beam Profiling Camera or Scanning Slit Beam Profiler.
Also refer to M² Measurement & Analysis, as this requires the simultaneous measurement of divergence and beam waist diameter.
If you are unsure as to which is most suitable for your application, please contact us or filter by your application criteria.