News: Optoelectronics
1 April 2025
Casela launches 16-channel External Laser Source platform
High-power semiconductor laser designer Casela Technologies of Santa Clara, CA, USA has launched the ELSA-16, a pluggable 16-channel External Laser Source (ELS) platform designed to unlock new levels of performance, flexibility and scalability in co-packaged optics (CPO) and silicon photonics-based systems powering AI workloads.
Engineered for the rapidly evolving demands of AI infrastructure, the ELSA-16 integrates 16 high-power distributed feedback (DFB) lasers with advanced control electronics in a compact, thermally optimized form factor. With optional TEC (thermoelectric cooler) integration for enhanced wavelength stability, the platform is fully customizable to target specific power, wavelength and efficiency requirements. ELSA-16 modules utilize polarization-maintaining (PM) fiber outputs and an OSFP electrical interface with CMIS-based firmware for seamless integration.
“The ELSA-16 represents a quantum leap in flexible and scalable external laser sources,” claims co-founder & CTO Milind Gokhale. “From powering high-bandwidth chiplet I/O to enabling dense wavelength division multiplexing, ELSA-16 is the ideal solution for next-generation optical networks.”
Key features of the ELSA-16 platform include:
- Customizable power profiles: Supports Casela’s 200–300mW-class lasers with fiber-coupled output powers ranging of 150–200mW per channel;
- Broad wavelength support: Available in 1310nm and CWDM-4 options for DR/FR links, and CW-WDM/DWDM variants for ring-based silicon modulators;
- Comb source capability: Enables up to 128 optical channels via 16 x 8-comb source configurations, with >12mW per wavelength per fiber on a 200GHz grid;
- DWDM scalability: Future-ready for tighter wavelength spacing and dynamic control to support evolving CPO architectures.
As AI and high-performance computing continue to demand ultra-efficient and high-bandwidth I/O, Casela claims that its ELSA-16 platform delivers industry-leading wall-plug efficiency, precise wavelength control, and unparalleled scalability. With support for high-density, parallel optical links, ELSA-16 offers a path toward more compact, power-efficient and cost-effective optical interconnects at the silicon level.
In meeting room 6549 at the Optical Fiber Communications Conference & Exposition (OFC 2025) in San Francisco (30 March–3 April), Casela is showcasing a 16-wavelength version of ELSA-16, each powering dense comb sources to demonstrate the platform’s potential to support 128+ channels in a compact, pluggable form — redefining the limits of scalability in AI and HPC systems, it is claimed.
On 30 March, Gokhale joined a panel of industry leaders during the ‘High Power and Multi-Wavelength Laser Light Sources’ workshop at OFC. The group explored how innovation in laser architecture, integration and performance will drive the next generation of optical interconnects for AI/ML. Topics included multi-wavelength roadmaps, serial and parallel interface demands, high-efficiency packaging and the scalability required for future systems.
