How to Build a Compact Optical Transmitter for Data Networks

This patent describes a tiny, self-contained package for an optical transmitter that includes a laser, a cooling system, and lenses, all precisely aligned to send light signals into an optical fiber.

What it covers

This patent details a compact, packaged optical transmitter device. It uses a base member with a flat part that holds a thermoelectric cooler module, a transmitter module, and an optical coupling lens, along with an assembling part on its side (Claim 1). A circuit board is bent so one end connects to the cooler and transmitter on the flat part, while the other end, raised higher, has an electrical port for outside connections (Claim 1). A cover sits over the main components. Crucially, a cylindrical part attaches to the assembling part, holding an isolator and a second lens, which are precisely aligned to guide the light signal from the transmitter into an external optical fiber (Claim 1). For example, this design allows a tiny laser diode (Claim 3) to be kept at a stable temperature by the cooler (Claim 2) and its light accurately directed into a hair-thin fiber.

What it doesn't cover

• —Does not cover optical transmitters that do not use a thermoelectric cooler for temperature regulation.
• —Does not cover devices where the circuit board is not bent or where its electrical port is not raised to a higher level.
• —Does not cover optical coupling systems that lack both an isolator and a second lens for connecting to an optical fiber.
• —Does not cover packaging where the optical components cannot be precisely aligned using specific plane and distance adjusting mechanisms.
• —Does not cover the individual components like laser diodes or isolators when they are not part of this specific integrated package.

The clever bit

The novelty lies in the highly integrated and adjustable packaging design. It combines thermal control, a bended circuit board for space efficiency, and multiple lenses with precise alignment mechanisms into a single, small form factor, ensuring stable and efficient optical signal coupling.

Why it matters

This patent addresses the challenge of making optical transmitters smaller, more reliable, and easier to manufacture. By integrating thermal management, precise optical alignment, and electrical connections into a single, compact package, it enables higher data rates and greater density in network equipment. This is vital for modern data centers and telecommunication networks that demand ever-increasing bandwidth in smaller physical footprints.

Real-world examples

• 1.QSFP-DD optical transceivers
• 2.Coherent optical modules for long-haul networks
• 3.Transmitter components in fiber-to-the-home (FTTH) systems
• 4.High-speed optical interconnects for data centers