US 12,300,967 B2
Method and system for controlling laser modulation
William Redman-White, Southampton (GB); Dominique Coue, Southampton (GB); and Colin Whitfield, Southampton (GB)
Assigned to HILIGHT SEMICONDUCTOR LIMITED, (GB)
Filed by Hilight Semiconductor Limited, Southampton (GB)
Filed on Dec. 2, 2022, as Appl. No. 18/074,063.
Claims priority of application No. 2117528 (GB), filed on Dec. 3, 2021.
Prior Publication US 2023/0178962 A1, Jun. 8, 2023
Int. Cl. H04B 10/00 (2013.01); H01S 5/06 (2006.01); H01S 5/062 (2006.01); H01S 5/0683 (2006.01); H04B 10/50 (2013.01); H04B 10/516 (2013.01)
CPC H01S 5/06835 (2013.01) [H01S 5/0617 (2013.01); H01S 5/06233 (2013.01); H04B 10/503 (2013.01); H04B 10/516 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A system for communication wherein information is transmitted in at least one burst, the system comprising:
drive circuitry coupled to a laser diode, said drive circuitry configured to apply, in a start-up phase prior to an operating phase, a first drive current and then a second drive current to flow through said laser diode, said first drive current and second drive current being different and such that said laser diode is configured to provide a first optical output and a second, different, optical output respectively;
a compensating current source further coupled to a terminal of said laser diode, said compensating current source configured to provide a current related to the first and second drive currents and further configured to not to flow through said laser diode and configured to maintain a combined current flowing through at least one impedance connected to said laser diode at a substantially constant level during the said start-up phase;
an optical sensor configured to provide a first sensor output corresponding to said first optical output of said laser diode and a second sensor output corresponding to said second optical output; and
a controller configured to use a value of said first drive current, a value of said second drive current, said first sensor output, said second sensor output and at least one supplied input value to provide control values for said drive circuitry to control an operating current of said laser diode during the operating phase wherein the information is transmitted in the at least one burst.