A Common Classification of Optical Devices
Optical Devices refer to photoelectronic devices with various functions which are made of photoelectric conversion effect and are the main components of Optical Transceivers.
According to the work of whether the need for external energy drive photoelectric conversion classification, optical devices are divided into Active Devices and Passive Devices; The former is the optical communication system in the need of external energy drive work, and can convert electrical signals into optical signals or optical signals into electrical signals, is the heart of the optical transmission system; The latter is a photoelectronic device that does not need external energy to drive, which mainly includes Fiber Optical Connector, Fiber Optical Coupler, WDM, Optical Attenuator and Optical Isolator, etc., and is the joint of optical transmission system.
In Active Devices the Device that converts electrical signals into optical signals is called light source, and the Device that converts optical signals into electrical signals is called light detector. Among them, the light source devices are mainly Semiconductor Light-emitting Diode (LED) and Laser Diode (LD), photodetector is mainly Positive Intrinsic-Negative (PIN) and Avalanche Photodiode (APD).
According to the functional classification, Optical Devices can be classified into Transmitting and Receiving devices, WDM Devices, Gain Amplification Devices, Switching devices and System Management Devices. Among them, the Transmitting and Receiving devices were separated into two independent components in the early stage -- Transmitting Optical Sub-Assembly (TOSA) and Receiving Optical Sub-Assembly (ROSA), until later with the development of miniaturization, the two were combined into the " Bi-Directional Optical Sub-Assembly" (BOSA) with both transceiver functions.
Specifically, there are about 9000 different types of Optical Devices.