What is a Butterfly Package?

The butterfly package is a common packaging solution for optical communication devices, named for its butterfly-like shape.

The housing of a butterfly package is generally a cuboid. Optoelectronic devices feature complex internal structures and diverse functions, which demand ample internal space. The interior is mainly divided into two sections: one holds optical components such as lasers, optical amplifiers, optical modulators, photodetectors, lenses and optical isolators; the other accommodates electronic components including thermistors, heat sinks and coolers.
The spacious interior of the butterfly shell enables easy mounting of semiconductor thermoelectric coolers (TECs). Its large metallic surface ensures superior heat dissipation, supporting reliable temperature control. Meanwhile, components like SOA chips and lenses can be flexibly arranged inside the housing. Pins are distributed on both sides, simplifying wire bonding and circuit connection for internal parts. Furthermore, this structure is convenient for testing and packaging.
Butterfly-packaged optoelectronic devices boast regular dimensions, light weight and high reliability after hermetic sealing. They can be easily manufactured and assembled into modules for a wide range of industrial applications, and are thus widely used in modern optical communication and fiber optic sensing systems.
Butterfly devices are typically specified by the number of extended pins. The 14-pin (14P) dual-sided package is the mainstream type, and 8-pin (8P) dual-sided versions are also available in small quantities. There are also compact single-sided models with 8 pins or 6 pins.
In terms of optical path design, butterfly devices fall into two categories: single-side fiber output and dual-side fiber output. Single-fiber output is mostly applied to semiconductor lasers, while dual-fiber output is commonly used for Semiconductor Optical Amplifiers (SOAs).
All butterfly-packaged SOAs produced by Jianhe Bafang adopt the 14-pin design, and customized products are available to satisfy customers’ personalized requirements.