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/e 2 beam diameter and beam divergence; for lasers, beam diameter is given for TEM 00 mode. Spot size visibility varies based. Whether a diode laser is a traditional monolithic design or utilizes an external cavity configuration, the laser light must still propagate through the diode's PN-junction via a ridge waveguide. As a result, the beam profile of edge emitting diodes is unique when compared to all laser sources. Lasers produce highly coherent, directional beams of monochromatic light.