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Laser Spot Size Calculator

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Input Beam Diameter, DI (mm):


Beam Divergence, θI (mrad):


Working Distance, L:

Output Beam Diameter, DO (mm) --     

Infinite Conjugate Tube Length
$$ D_O = D_I + 2 \left[ L \cdot \tan{\left( \frac{\theta _I}{2} \right)} \right] $$
DI: Input Beam DiameterDO: Output Beam Diameter
θI: Beam DivergenceL:Working Distance

Note: This list is updated periodically and may not reflect our most current laser and laser diode product offerings.


Determine spot size of our lasers and laser diode modules from user supplied working distances. Calculator provides circular or elliptical spot size approximations based on 1/e2 beam diameter and beam divergence; for lasers, beam diameter is given for TEM00 mode. Spot size visibility varies based on ambient light conditions.

Related Resources and Products

 Application Note

Laser Sources

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