Beam Divergence Calculator
Aperture dia. mm  

Divergence is the angle the beam is expanding. It is usually in the units of milli-radians. (mrad)

Use this to determine the beam divergence given 2 beam diameter values at a given separation.

Distance m  
Second dia. mm  
Divergence mrad  
Beam Diameter at Lens Calculator
Divergence mrad If you know your the aperture at the laser tube, the divergence and the length from the tube aperture to the lens, you can calculate the beam diameter at the lens.
Aperture mm
Distance m  
Diameter at lens mm  
Spot Size Calculator
Beam dia. (D) mm Spot Dia. = 1.27 * f * wavelength * M2/D

Calculate the focused spot size
M = 1 for a perfect gaussian TEM00 beam FAQ

Wavelength mm  
Focal Length (f) mm  
Focused spot size mm  
Beam Power watt  
Power Density w/mm2  
Depth of field Calculator
Beam dia. mrad DOF = 2.5 * wavelength * (f/D)2

What is the length of the beam in the area where the beam is less than 140% of the spot size. FAQ

Focal Length mm
Wavelength mm
Depth of field mm  


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