Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
93 words
A lightwave transmitter comprising a semiconductor laser (27) and a driver circuit (25) for modulating said laser with a modulation current (Imod), CHARACTERIZED in that a reference circuit (20) is located in thermal proximity to said laser, and includes means (21) for increasing the magnitude of said modulation current as a function of temperature at a given rate up to a given temperature (T g ) of said laser, and means (22, 23, 24) for increasing the magnitude of said modulation current at a more rapid rate at temperatures above said given temperature.
Claim 2
Dependent Claim
93 words
A lightwave transmitter comprising a semiconductor laser (27) and a driver circuit (25) for modulating said laser with a modulation current (Imod), CHARACTERIZED in that a reference circuit (20) is located in thermal proximity to said laser, and includes means (21) for increasing the magnitude of said modulation current as a function of temperature at a given rate up to a given temperature (T g ) of said laser, and means (22, 23, 24) for increasing the magnitude of said modulation current at a more rapid rate at temperatures above said given temperature.
Claim 3
Dependent Claim
21 words
The lightwave transmitter of claim 1 wherein said driver circuit and said reference circuit are formed in the same integrated circuit.
Claim 4
Dependent Claim
19 words
The lightwave transmitter of claim 1 wherein said given rate is proportional to the absolute temperature of said reference.
Claim 5
Dependent Claim
23 words
The lightwave transmitter of claim 1 wherein said more rapid rate is proportional to the difference of said given rate and a constant.
Claim 6
Dependent Claim
14 words
The lightwave transmitter of claim 1 wherein said reference circuit is a bandgap reference.
Claim 7
Dependent Claim
26 words
The lightwave transmitter of claim 1 wherein said given temperature is in the range of 40 to 90 degrees C as measured at said reference circuit.
Claim 8
Dependent Claim
19 words
The lightwave transmitter of claim 1 further comprising means (26) for supplying a bias current (Ibias) to said laser.
Claim 9
Dependent Claim
29 words
The lightwave transmitter of claim 7 further comprising backface monitoring means for controlling said bias current so that the total optical output of said laser is maintained relatively constant.
Claim 10
Dependent Claim
21 words
The lightwave transmitter of claim 7 further comprising means for maintaining said bias current in proximity to the laser threshold current.
Claim 11
Dependent Claim
31 words
The lightwave transmitter of claim 1 further comprising means for adjusting the value of said more rapid rate, whereby lasers having differing characteristics of optical output verses temperature may be compensated.
Claim 12
Dependent Claim
37 words
The lightwave transmitter of claim 1 further comprising means for normalizing the magnitude of said modulation current to a value chosen at a given temperature, so that the optical power output of said laser may be chosen.