A Notch-Saddle-Compensation Technique in Butterfly-Type Laser Module Packages

An Oriented-Dependence-Microlens Visual Alignment and Packaging for Lasers Coupling to PMFs

“…By contrast, the butterfly laser packages [10]- [13] of the boxed-type designs are often used in higher performance devices that require a higher power output, a higher speed, a higher reliability, a thermoelectric cooler, and multiple components. In the process of packaging a butterfly laser package, a dual-beam laser welding system was used to connect the fiber ferrule assembly to the laser diode [9], whereas a three-beam laser welding system was used to connect the fiber ferrule to the laser diode in a TO-Can laser package [10].…”

“…There were a total of eight welded spots on the laserwelded saddle-shaped clip-metallic plate and saddle-shaped clip-fiber ferrule joints during the packaging process, as shown in Fig. 7 (a) [9], [10]. However, there were only four symmetric welding joints in a dual-beam laser welding system for butterfly-type laser module.…”

“…The welding joint 1 and 2 were sequentially defined first to join the saddle-shaped clip and metallic plate, and the welding joint 3 and 4 were sequentially defined to join the saddle-shaped clip and fiber ferrule, as shown in Fig. 7 (b) of module and welding joints [9]. The advantage of such a laser welding sequence was that it offered less welding induced alignment distortion during the solidification shrinkage [9], [10].…”

“…7 (b) of module and welding joints [9]. The advantage of such a laser welding sequence was that it offered less welding induced alignment distortion during the solidification shrinkage [9], [10]. In addition, a postweld shift (PWS) correction method was used that the fiber tip shift due to the PWS could be realigned back closer to their original optimum position [8]- [10].…”

“…In addition, a postweld shift (PWS) correction method was used that the fiber tip shift due to the PWS could be realigned back closer to their original optimum position [8]- [10]. The coupling efficiency of the laser modules after PWS was typically more than 70% [9]. Figure 7 indicated that a practical package of laser/PMF module with compact size and few components employing the ODM was demonstrated.…”