Study On The Key Techniques Of Fiber Active Devices Packaging With Laser Welding

Fiber-optic active device is the base of fiber network and very important in the field of optic communications.It is mostly applied in the local area network.At present,pulsed laser welding is widely used in the package of fiber-poptic active device. Small welding spot,high density power and small hot influence area are its' features.In the package,the post-weld-shift(PWS),which appear because the metal shape change,will reduce the light coupled power.In the paper, a device for measuring PWS is designed.It can measure PWS direction and magnitude in real time,according to which,the laser hammering can readjust PWS.The packaging quality will be increased.The model of LD(laser diode) is builded by Ansys.PWS is simulated when the welding spots' power are equal.The regularity of direction and magnitude of PWS is found.According to which,the device for measuring PWS is designed.In the paper,a device for measuring PWS is designed based on the theory of strain electrical measurement.The device consists of three parts:the resistance strain sensor,the machanism for measuring PWS and the conditioning circuit for electric bridge signal.The static characteristic and the work curve of the resistance strain sensor are calibrated.The direction and magnitude of PWS are measured in the experiments of LD packaging.The result indicate that the laser hammering technology well correct the PWS.After the correcting number is less than six,the light coupled power can rise above 90% of the initial power.The experiment effect is all right.