Beam Optimized Processing Of High Power Semiconductor

Semiconductor laser is an electro-optic converter with fast development,great achievements,wide penetration and wide application field in recent decades.Due to the advantages of small volume,high efficiency,low cost,high integration and wide wavelength coverage,it is widely used in laser display,infrared night lighting,medical,communications,military and pumped solid-state laser technology,and has become an important direction of the current development of laser industry application.In the night lighting,the wavelength of near infrared semiconductor laser at 800-1000nm has obvious advantages,such as high photoelectric conversion,long lifetime,and long lighting distance,all of which LED infrared lighting is unable to achieved;semiconductor laserswith wavelength larger than 900nm show no red storm,thus are widely used in railway and highway etc..The semiconductor laser shows some weakness as infrared lighting due to its luminescence properties,such as the ovalluminous spot for the far field,which can be seen as a long spot from dozens of centimeters away.Moreover,the divergent angle is of 40 degreesat the longitudinal direction,which affects the transmission distance of the beam;the laser beam interference leads to the snow spot in lighting.In view of the actual requirements of applications,several methods are proposed for the multiple beam compression.Analysis results can be applied to different distance lighting.Different ways are used to homogenize the beam spot and eliminate snow spot,the nebula and other phenomena.In the semiconductor laserpump,fast axis compression isalso need so as to obtain auniformdistribution of pump light power,to ensure that the laser work in the fundamental transverse mode.Based on the further study of the fast axis compressionof single longitudinal mode laser beam under uniform pumping experiment,we put forward the high refractive index material as a new material for frequency selection.Experiments show that the materials with high refractive index give rise to larger longitudinal mode interval and more conveniencein the process of adjustment.Fiber couplingis another kind of technology of semiconductor laser beam shaping.The elongated beam of the laser diode with round spot of flexible output is easier to use.The heat source and the device are apart,reducing the heat affectation.In this paper,450nm blue laser is used as an example to obtain indirect coupling output,and the coupling efficiency is 88%.As for the fiber laser used in mechanical techniques,semiconductor laser shows its importance as pump source in this field.The optical power density directly determinesthe processing capacityin the field,such as thesteel thickness,the edge effect in the process of cutting,processing speed.The light power density depends on the fiber laser conversion efficiency,while the light power density is ultimately attributed to the output of semiconductor laser.There are two things that have been pursued at the moment,the first is the size of single emittingchip,and the other is the alignment of the beam in space as it goes into the fiber.In addition,there are also some polarization coupling by the polarization characteristics of semiconductor lasers orwavelength couplingby semiconductor laser wavelength difference,but these are based on the spatial combination.This paper will introduce a slight.The technology has developed greatly in near infrared region,but it is not reported in the visible range.In this paper,the technique of space beam combining is applied to the experiment of high power red light.Two kinds of space beam combining methods of unequal optical path and equal optical path are adopted,a high brightness fiber output device of 660nm 9.2W laser is obtained.