Abstract: A circuit which improves the linearity of a high power laser diode is disclosed. A electrical diode is coupled to the anode of the laser diode and a filter/bias network back biases the laser diode and forward biases the PN diode. At lower current levels the amount of current flowing through the laser diode is lowered. At higher current levels, rolloff in the PN diode allows more current through the laser diode. The rolloff performance of the laser diode and PN diode mirror each other closely enough to improve the laser's linear performance by 3 dB to 5 dB.

Abstract: An error compensation system is described which provides a linear laser signal. The error compensation system includes a first high power linear laser which is used to drive a signal onto an optical fiber. The signal on the optical fiber is tapped to provide a signal representative of the signal on the fiber. This tapped signal is compared with the original modulated signal to produce a control signal indicative of any error signal on the fiber. This control signal is inverted and used to drive a lower power laser which supplies an optical output indicative of the inverted error. By properly combining the original signal with an inverted error signal, a corrected signal may be detected from the fiber for distribution.