Lessengers unveiled a 1.6T OSFP 2×SR4 multimode optical transceiver at OFC 2025, designed to meet the escalating bandwidth and energy demands of hyperscale AI/ML data centers. The new transceiver supports 8×224G PAM4 electrical lanes and leverages Lessengers’ patented Direct Optical Wiring (DOW) technology to reduce power consumption and cost while ensuring high-speed, short-reach connectivity over multimode fiber (MMF), the dominant medium within modern data centers.
This 1.6T transceiver is optimized for less-than-100m intra-rack and intra-row links—common in AI clusters—using 200G PAM4 VCSELs and dual MPO12 connectors. It is compliant with OSFP MSA, IEEE P802.3dj, and OIF CEI-224G specifications, and supports three interface types: LPO (5W), LRO (11W), and Retimed (17W), giving data center operators a flexible range of power budgets and latency profiles. The use of DOW eliminates lens optics, enhancing optical coupling efficiency and reliability, especially in dense compute environments.
In addition to debuting the 1.6T transceiver, Lessengers is demonstrating 800G and 400G transceivers, active optical cables, co-packaged and near-packaged optics, and immersion cooling compatibility at booth 5221. This positions the company as a key enabler of scalable, efficient optical interconnects for next-generation hyperscale infrastructure.
• Lessengers launches first 1.6T OSFP 2×SR4 transceiver with multimode optics at OFC 2025.
• Based on 8×224G PAM4 electrical lanes, with 200G PAM4 VCSELs and dual MPO12 connectors.
• Supports LPO (5W), LRO (11W), and Retimed (17W) modes.
• Compliant with OSFP MSA, IEEE P802.3dj, and OIF CEI-224G standards.
• DOW technology enables lens-free, low-power, cost-efficient optical coupling over MMF.
“We are excited to unveil our new 1.6 Terabit capacity transceiver at OFC 2025, which will showcase a number of groundbreaking optical innovations for the hyperscale data center,” said Chongcook Kim, CEO of Lessengers.
- Lessengers’ Direct Optical Wiring (DOW) technology is an innovative approach to optical interconnects that utilizes polymer-based air-cladded waveguides to directly connect active photonic devices, such as laser diodes or photodiodes, to optical fibers. This method eliminates the need for lens optics, thereby reducing potential errors and optical impairments that can affect signal quality and transmission efficiency. DOW technology enables high-density, high-speed optical signal connectivity, making it particularly beneficial for data centers and high-performance computing environments.




