The Fusion Record — Fusion Energy News ← Home · Knowledge base
Companies & Programs

EX-Fusion

A Japanese laser-fusion startup pursuing direct-drive inertial confinement — inspired by the Institute of Laser Engineering's decades of implosion research.

Reviewed Last reviewed: 9 Aug 2026 · Category: Companies & Programs

Overview

EX-Fusion is a Japanese fusion energy startup focused on laser-driven inertial confinement fusion (ICF). Founded in Osaka, the company builds on the scientific legacy of the Institute of Laser Engineering (ILE) at Osaka University, which has been a world leader in direct-drive laser fusion research for over forty years.[1]

Technical Approach

EX-Fusion pursues direct-drive ICF, in which laser beams illuminate a fuel capsule uniformly from all sides, directly ablating the outer shell and driving a symmetric implosion that compresses and heats the deuterium-tritium fuel to fusion conditions. This contrasts with the indirect-drive approach used at the U.S. National Ignition Facility (NIF), where laser energy first converts to X-rays inside a hohlraum.[2]

Direct drive offers higher coupling efficiency between laser energy and fuel kinetic energy, potentially enabling ignition at lower total laser energy. However, it demands extremely uniform laser illumination and precise target fabrication to suppress hydrodynamic instabilities during implosion.

Heritage

The ILE's GEKKO-XII laser system and its successor facilities have contributed fundamental advances in implosion physics, fast ignition, and laser-plasma interaction science. EX-Fusion's founders and technical advisors include researchers from this program, bringing deep expertise in target physics, laser technology, and diagnostics.[3]

Japan's ILE pioneered the fast-ignition concept, which separates compression from heating using an ultra-intense short-pulse laser — a scheme that could dramatically reduce the driver energy required for ICF power plants.

Outlook

EX-Fusion faces the common ICF challenge of achieving high repetition rates (multiple shots per second) with affordable targets and durable chamber materials. The company is also exploring near-term applications of its laser and target technology, including materials processing and industrial inspection, to generate revenue while developing the fusion energy system.

Sources

  1. EX-Fusion Inc. Company profile and technical vision. ex-fusion.com, 2023.
  2. Azechi, H. et al. Comprehensive diagnosis of growth rates of the ablative Rayleigh-Taylor instability. Physical Review Letters, 98, 045002, 2007.
  3. Kodama, R. et al. Fast heating of ultrahigh-density plasma as a step towards laser fusion ignition. Nature, 412, 798-802, 2001.

Related