CWDM was standardized by the ITU-T G. 2 based on a grid or wavelength separation of 20 nm in the range of 1270-1610 nm. Each wavelength does not affect another wavelength. Wavelength Division Multiplexing (WDM) allows multiple data streams to be transmitted simultaneously over a single optical fiber. The term "Coarse" refers to the.
[pdf] A laser diode (LD, also injection laser diode or ILD or semiconductor laser or diode laser) is a device similar to a in which a diode pumped directly with electrical current can create conditions at the diode's. Driven by voltage, the doped p–n-transition allows for of an electron wit.
[pdf] Laser diodes are semiconductor lasers with a current-carrying p–n junction as the gain medium. They are the most important type of electrically pumped lasers. In such a heterostructure of a bipolar interband laser, electrons and holes can recombine, releasing the energy. Laser diodes (LD) are semiconductor devices that convert electrical energy into high-power optical energy.
[pdf] This coherent light is produced by the laser diode using a process termed as “Light Amplification by Stimulated Emission of Radiation”, which is abbreviated as LASER. And since a p-n junction is used to produce laser light, this device is named as a laser diode. A laser diode (LD, also injection laser diode or ILD or semiconductor laser or diode laser) is a semiconductor device similar to a light-emitting diode in which a diode pumped directly with electrical current can create lasing conditions at the diode's junction. The intrinsic layer is sandwiched between the P-type and N-type layer. Metal plates are connected with p-layer and n-layer to form the terminals anode (+) and cathode (-) respectively.
[pdf] 
