Patent ID: 6917639
Filing Date: 2005-07-12
Classification: H01S

Abstract:
1. A laser driver circuit, comprising: a biasing current source for supplying a bias current to a laser diode continuously with a level such that no laser oscillation is caused in said laser diode; a threshold current source for supplying a threshold current to said laser diode with a level causing optical emission but not causing substantial laser oscillation in said laser diode; and a modulation current source for supplying a modulation current to said laser diode in response to an input signal such that a laser oscillation occurs in said laser diode in response to said modulation current, wherein said threshold current source produces said threshold current in response to said input signal with a timing of 1-10 ns in advance of a leading edge of said modulation current and with an interval of said threshold current exceeding an interval of said modulation current such that said interval of said threshold current includes said interval of said modulation current, said laser driver circuit driving said laser diode by a sum of said bias current, said threshold current and said modulation current.