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:
Mar. 12, 2019
Filed:
Jul. 11, 2018
Shimadzu Corporation, Nakagyo-Ku, Kyoto-Shi, Kyoto, JP;
SHIMADZU CORPORATION, Kyoto, JP;
Abstract
A semiconductor laser driving circuit that ensures the satisfied extinction ratio, the accuracy of the light output, and enables the light output dynamically to change based on a modulation signal. The semiconductor laser driving circuit includes a semiconductor laser LD of which the laser light is modulated by the analog modulation signal v_MOD, the differential pair circuit having impedance elementsand transistors Q, Q, a power source, a differential driverthat generates a differential voltage to switch on-and-off the transistors Q, Qby an analog modulation signal, a threshold electric current generation element that generates the threshold electric current to flow the threshold that the semiconductor laser emits, a slope signal generation elementthat generates a slope signal V_SLOPE by executing a level conversion by a predetermined slope coefficient relative to the analog modulation signal, and an adderthat adds a slope signal, which the slope generation element generates and the threshold electric current that the threshold electric current generation element and controls the electric current or the power source by the addition output.