Lightmatter가 Open CPX Multi-Slice Architecture 이니셔티브에 참여하며, 송수신을 단일 코어로 통합해 파이버 케이블링을 절반으로 줄이는 Passage L20 CPX 광엔진을 공개했다.

MOUNTAIN VIEW, Calif., Sept. 17, 2026 — Lightmatter today announced its participation in the Open CPX Multi-Source Agreement (MSA) alongside the launch of the Passage L20 CPX, the industry’s first Open CPX module for AI infrastructure featuring bidirectional (BiDi) optical link technology. Powered by the Passage L20 optical engine—Lightmatter’s near-package optics (NPO) platform unveiled in March—the module delivers 6.4 terabits per second (Tbps) in a single socketed form factor while cutting the required fiber and connectors in half.

Fiber availability is increasingly becoming a bottleneck for AI cluster construction. Conventional links require separate fibers for transmission and reception, whereas BiDi technology merges both directions onto a single fiber using distinct wavelengths. According to Lightmatter’s analysis in a recent technical brief, deploying this architecture in a 512-GPU scale-up pod reduces fiber requirements by more than 200 miles, dropping the count from approximately 130,000 to 65,000, while eliminating roughly 16,000 connectors. This consolidation reduces potential failure points, cuts total scale-up interconnect network costs by approximately 15 percent, accelerates deployment, and streamlines both fiber plant maintenance and long-term operational expenses.

“AI infrastructure is scaling faster than copper can follow, and co-packaged optics is the answer. CPX is the on-ramp. It gets the optics, the fiber, and the supply chain into production now, so that when CPO arrives, the hard parts are already proven. That’s why we joined the Open CPX MSA,” said Nick Harris, Ph.D., Founder and CEO of Lightmatter. “Passage L20 CPX is bidirectional and enables transmit and receive over a single fiber, which halves fiber requirements. At cluster scale that means faster bring-up, fewer failures, and less time chasing broken links.”

“As AI clusters scale up, the constraints are shifting from compute to the physical infrastructure around it, including power, cabling, and the time it takes to bring a pod online,” said Sameh Boujelbene, Vice President at Dell’Oro Group. “Standardization efforts like the Open CPX MSA are critical to commercializing optics close to the package across a broad multi-vendor ecosystem. A bidirectional architecture that halves fiber count without giving up bandwidth addresses a cost and complexity problem that operators feel immediately.”

The Open CPX MSA establishes a standardized form factor for CPO/NPO modules designed to deliver high-bandwidth, low-latency I/O directly adjacent to host ASICs, switches, or GPUs. By mounting directly to the PCB or substrate, the design adapts seamlessly to various XPU and switch board architectures. Unlike pluggable systems, where bandwidth density is constrained by faceplate real estate, positioning NPO near the XPU eliminates this limitation, boosting density while lowering both cost and power consumption relative to traditional pluggable transceivers.

Built on the Passage L-Series optical engine platform, the Passage L20 CPX delivers 12.8 Tbps of aggregate bandwidth (6.4 Tbps transmit and 6.4 Tbps receive) across 32 optical lanes per direction at a 212.5 Gbps PAM4 line rate. The module utilizes the MSA-defined Type 2 single RF+MP pin field, supports distances exceeding 500 meters over single-mode fiber, adheres to the IEEE 802.3dj DR link architecture, and implements OIF-CMIS management protocols. It operates on O-band wavelengths of 1331 nm and 1311 nm, pairing with Lightmatter’s Guide DR laser module or other compatible external laser sources. An XPO form factor is also available.

Evaluation kits for the Passage L20 CPX module are scheduled for customer shipment in the first quarter of 2027. All specifications referenced in this release are preliminary and subject to modification. Performance and cost metrics derive from internal testing and modeling under controlled conditions; actual outcomes may vary based on specific configurations and deployment environments.

About Lightmatter

Lightmatter is transforming AI data center infrastructure to enable the next generation of computational progress. Its Passage platform—the world’s first 3D-stacked silicon photonics engine—and Guide, the industry’s first VLSP light engine, connect thousands to millions of processors. Engineered to eliminate critical data bottlenecks, Lightmatter’s technology provides unprecedented bandwidth density and energy efficiency for advanced AI and high-performance computing workloads, fundamentally redefining next-generation AI infrastructure architecture. For more information, visit www.lightmatter.co.