The shrinkageless technology of the laser pigtails packaging

We have developed a technique for semiconductor laser diode to single-mode optical fiber pigtailing and packaging based on the use of an hemispherical microlens, formed on the optical fiber tapered end and packaging with minimum shrinkage. These microlenses provide up to 90% coupling efficiency between the single-mode laser and the single-mode optical fiber against the theoretical limit. The proposed technology does not require extra glass or crystal materials. By using a special alloy, which consists of several metals with different thermal coefficients, we achieved a so-called "shrinkageless" technology of fastening solder alloy and, consequently, minimum misalignment between the laser and the optical fiber.