A laser diode is a semiconductor device that emits coherent light through the process of stimulated emission. As a result, the beam profile of edge emitting diodes is unique when compared to all laser sources. Beam Diameter: The beam diameter refers to the diameter of the laser beam measured at the exit face of the laser housing. : 3 Driven by voltage, the doped. e laser diode beams are reviewed. The characteristics of a laser diode beam propagating through optical elements is analyzed using three commonly used math tools: analytical tool thin lens equation and ABCD matrix, numerical cal ulation, and software tool Zemax. The emitted light waves have the same wavelength, frequency, and.