The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 21, 2006
Filed:
Aug. 14, 2003
Daniel Scott Hedin, Rochester, MN (US);
Matthew James Paschal, Rochester, MN (US);
Daniel Scott Hedin, Rochester, MN (US);
Matthew James Paschal, Rochester, MN (US);
JDS Uniphase Corporation, San Jose, CA (US);
Abstract
The invention relates to a feedback loop for a laser diode driving circuit for ensuring that the laser diode generates optical power at a constant safe level. The feedback loop includes a monitor diode, which generates a monitor current I, and a set resistance for generating a set voltage based on the monitor current and the set resistance. The set voltage is compared with a reference voltage in an operational amplifier, which generates a control signal for controlling the laser diode current source. The laser diode current source dictates the amount of bias current transmitted to the laser diode. Safety features, in the form of voltage comparators, are provided to ensure that: a) the feedback loop is closed, i.e. Iis not too low; b) the optical power is not above standard safety threshold, i.e. Iis not too high; and c) the monitor diode voltage is sufficient to provide specified optical power to electrical power conversion.