8 December 2020
POET launches LightBar remote laser light sources
POET Technologies Inc of Toronto, Ontario, Canada — designer and developer of the POET Optical Interposer and photonic integrated circuits (PICs) for the data-center and telecom markets — has completed and tested its designs for a line of high-performance remote laser light source products for 400G FR4, 800G and co-packaged optics (CPO) applications in cloud data centers.
For makers of conventional and silicon photonics-based optical transceivers, the LightBar product line offers a fully aligned, tested and multiplexed laser light source attached to an output fiber, eliminating the difficult and costly step of four laser alignments in optical transceivers. For makers of next-generation network switches that require the combination of switch components and optical components in a single package (CPO), using LightBar products can reduce heat generation within the package, which is a common cause of component failure. When used as a remote laser source, the LightBar is expected to improve overall system reliability for both transceiver and CPO applications by offering the ability to replace failed laser assemblies in the field, without disturbing other components and sub-assemblies. Laser failures have proven to be the cause of a large majority of sub-assembly failures in both optical transceivers and co-packaged optics applications.
LightBar products are configured as a transmit optical sub-assembly (TOSA) incorporating four continuous wave (CW) lasers into the waveguide matrix of POET’s proprietary Optical Interposer, meeting the CWDM4 and FR4 technical specifications. The 400G version is upgradeable to 800G with the incorporation of additional components. The LightBar is completely customizable and can support a wide range of output power from 15mW to 60mW, depending on the application.
In all cases, LightBar incorporates POET’s proprietary designs and assembly features that deliver what is claimed to be an industry-leading laser coupling efficiency of >80% (power loss = <1.0dB), while maintaining wafer-scale integration capability – said to be significantly better than the best results observed with competing integrated approaches. Better coupling efficiency allows the use of lower-power, more reliable lasers to achieve the same output. POET will begin sampling the LightBar product line to customers in first-quarter 2021. Following qualification with customers, the firm expects to begin volume production in fourth-quarter 2021.
According to LightCounting, the market for 400G optical transceivers in all formats will grow from an estimated $0.5bn in 2021 to over $3bn by 2025. The market for optical connectivity (chiplets in co-packaged optics) is forecasted to exceed $4bn in 2028.