To make laser diodes or LEDs light up, they must be supplied with current. LEDs and laser diodes are current-driven components, as the luminous flux is almost proportional to the electrical current. The current-voltage characteristic is also highly non-linear, so a very small increase in voltage can lead to a sharp increase in current. Operating a laser diode with a voltage source would therefore destroy it. In order to ensure constant and long-lasting operation, a suitable current source should be used instead of a voltage source. A laser diode driver provides precisely this suitable current. Laser diode drivers are usually DC/DC or sometimes AC/DC converters to which the laser diode is connected. Different currents are required for laser diodes. Accordingly, there are different laser drivers for the various applications. The current can also be pulsed quickly in order to achieve special properties with the laser. This allows high peak power or lower energy consumption to be achieved. Several channels or direct control are also possible special features of laser drivers in order to be adapted for special applications.
