A laser diode is a semiconductor-based PN junction device that converts electrical energy into coherent light energy through a process known as stimulated emission. It functions similarly to an LED, but the key difference lies in the mechanism of light generation and the nature of. The laser diode chip is the small black chip at the front; a photodiode at the back is used to control output power. These devices are capable of producing an intense laser ray with uniformly sized light waves. As a light source with excellent directivity and rectilinear propagation that enables easy control of energy, laser diodes are used.
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