Optical components — lasers and EMLs
BOTTLENECKEML laser output caps how many 800G transceivers the industry can build, and lead times at the dominant supplier already stretch past 2027.
Semiconductor lasers generating light inside transceivers and co-packaged optics. EML output specifically limits 800G/1.6T transceiver production capacity. Lumentum holds ~50-60% of 200G EML share with near-monopoly pricing; lead times extend beyond 2027.
Semiconductor light sources used inside transceivers and co-packaged optics; includes DFB lasers, electro-absorption modulated lasers (EMLs), VCSELs, and comb lasers; fabricated on InP or GaAs substrates.
What the evidence shows
EML supply is concentrated among three companies: Lumentum, Coherent, and Mitsubishi.
photoncap.netNvidia's $4B commitment to Lumentum and Coherent pushed EML lead times for other buyers beyond 2027.
techtimes.comAs of 2026, InP EMLs remain the preferred choice for 1.6T due to superior performance at high temperatures.
markets.financialcontent.comWho controls it
Where it sits in the stack
Takes in: InP or GaAs epitaxial wafers, MOCVD reactor time, facet-coating materials
Sends on: Laser die and sub-module chips for optical transceiver and CPO assembly
Related nodes
Full scorecard, owner shares, supply edges and the full tracked roster are in the desk letter.
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