US 12,278,458 B2
Light emitting assembly with a degradation determiner for the laser elements and for the optical system
Katsuya Samonji, Toyama (JP)
Assigned to NUVOTON TECHNOLOGY CORPORATION JAPAN, Kyoto (JP)
Filed by NUVOTON TECHNOLOGY CORPORATION JAPAN, Kyoto (JP)
Filed on Aug. 24, 2021, as Appl. No. 17/410,109.
Application 17/410,109 is a continuation of application No. PCT/JP2020/006076, filed on Feb. 17, 2020.
Claims priority of application No. 2019-034777 (JP), filed on Feb. 27, 2019.
Prior Publication US 2021/0384697 A1, Dec. 9, 2021
Int. Cl. H01S 5/00 (2006.01); H01S 5/024 (2006.01); H01S 5/06 (2006.01); H01S 5/062 (2006.01); H01S 5/0683 (2006.01); H01S 5/30 (2006.01); H01S 5/40 (2006.01)
CPC H01S 5/0021 (2013.01) [H01S 5/024 (2013.01); H01S 5/062 (2013.01); H01S 5/0683 (2013.01); H01S 5/0617 (2013.01); H01S 5/3013 (2013.01); H01S 5/4025 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A light source device, comprising:
a semiconductor laser element;
an optical system that includes a first optical element through which emission light emitted from the semiconductor laser element propagates;
a first light receiver that receives first propagating light that has propagated through at least a portion of the first optical element;
a laser driving controller that controls a driving current for driving the semiconductor laser element; and
a first received-light intensity measurer that measures a first output value that indicates a received-light intensity of the first propagating light that has been received by the first light receiver,
wherein the first light receiver is disposed downstream of the first optical element,
wherein the laser driving controller drives the semiconductor laser element by using a plurality of values of the driving current that are different from each other,
wherein the received-light intensity measurer measures the first output value of the first propagating light that has been received by the first light receiver for each of the plurality of values of the driving current that are different from each other,
wherein the light source device further comprises a degradation determiner that determines a degree of degradation of the first optical element,
wherein the degradation determiner determines the degree of degradation of the first optical element based on the plurality of values of the driving current that are different from each other and the first output value of the first propagating light that has been received by the first light receiver for each of the plurality of values of the driving current that are different from each other, and
wherein the degradation determiner determines the degree of degradation of the first optical element based on ΔPom/Δlf, where Δlf represents an amount of variation between two driving current values out of the plurality of values of the driving current that are different from each other, and ΔPom represents an amount of variation between the first output values of the first propagating light that has been received by the first light receiver that correspond to the two driving current values.