Packaging of photon sources

Light emitting diodes and laser diodes emit light. Light consists of photons.  Keeping in view, the application, packaging of photons is carried out in different ways.  Mainly there are two types of packaging- LED packaging and laser diode packaging.  LED packaging is of 4 types-TO packages, ST style, SC type and FC type. In TO type packaging, a metallic header is hermetically sealed with a flat or lensed window cap.  LED is now packed with a variety of standard connectors. These connectors have matched male and female components that are aligned when joined together.  Laser diode packaging is of two types –  uncooled laser diodes and cooled laser diodes.  Uncooled laser diodes are more reliable where diodes are mounted on a heat sink and are packed in dual in line package. Here additional cooling mechanism is not required. Non-radiative recombination generates less heat and operating power is very less. A cooled laser diode consists of a thermoelectric cooler with thermostat devices. Here heat gets transferred from laser diode to outside atmosphere allowing laser diode to remain at operating temperature.