What is a laser diode?

A Laser Diode or semiconductor laser is the simplest form of Solid-State Laser. Laser diodes are commonly referred to as edge emitting laser diodes because the laser light is emitted from the edge of the substrate. The light emitting region of the laser diode is commonly called the emitter. The emitter size and the number of emitters determine output power and beam quality of a laser diode. Electrically speaking, a laser diode is a PIN diode. The intrinsic (I) region is the active region of the laser diode. The N and P regions provide the active region with the carriers (electrons and holes). Initially, research on laser diodes was carried out using P-N diodes. However, all modern laser diodes utilize the double-hetero-structure implementation. This design confines the carriers and photons, allowing a maximization of recombination and light generation. If you want to start reading more about laser diodes, try this whitepaper “How to Improve Laser Diode Lifetime.” If you want to read more about the Laser Diode Types we offer, check out the Overview of Laser Diodes section on our Lasers 101 Page!