Modulating the output power of a laser diode can happen in two ways: by changing the signal input/driving current1,2 or by alternating the continuous wave output after the light is generated. 2 In laser modulation, the current or voltage varies with time to modulate the output signal from the laser. Laser modulation is a critical facet of laser technology, allowing for controlled variations in key parameters such as intensity, frequency, or phase. Such control opens the door to a broad range of scientific and commercial applications. Aerospace, automotive and biomedical industries all heavily. al electro-optic oracousto-optic modul ators. One of the most common types in use is. A series of simple and low-cost devices for switching, amplifying, and chirping diode lasers based on current modu-lation are presented.