Senior Optical Engineer - Stray Light

Xcimer Energy leverages decades of research on Inertial Fusion Energy (IFE) combined with groundbreaking new laser architecture. Our mission is to deploy fusion power plants to meet global decarbonization goals as fast as possible. Xcimer has assembled a team of leaders in tough tech, fusion science, and manufacturing with a track record of rapid execution. Supported by leading investors, Xcimer is uniquely positioned to deliver limitless, clean, fusion power to combat climate change. Join

us in powering a better world with inertial fusion!

This is a full-time, onsite role based at our headquarters in Denver, CO.

As a Senior Stray Light Optical Engineer, you will be the primary technical authority on non-sequential ray tracing and stray light mitigation. Your work will focus on modeling and designing complex optical layouts to identify and mitigate ghosts, hot spots, fringing effects, and other parasitic light paths that could degrade system performance or cause optical damage.

In this highly collaborative role, you will work closely with sequential optical designers, opto-mechanical engineers, material scientists, and optical systems engineers. You will implement mechanical feature models (e.g., baffles, beam dumps) directly into non-sequential software to validate their effectiveness. You will also write custom scripts to automate complex analyses and process large datasets, ensuring our high-energy DUV systems operate safely and efficiently.

Responsibilities

* Perform comprehensive non-sequential ray tracing (primarily using FRED software) to analyze stray light, ghost reflections, scattering, and diffraction in high-energy DUV laser systems.

* Identify and mitigate high-fluence "hot spots" and fringing effects to prevent optical damage and ensure system longevity.

* Implement and evaluate mechanical feature models (such as baffles, apertures, and beam dumps) within non-sequential environments to actively mitigate stray light.

* Write and maintain custom scripts (e.g., Python, MATLAB, or FRED script) to automate ray trace simulations, process large datasets, interface to other analysis tools and quantify system-level signal degradation.

* Collaborate cross-functionally with sequential optical designers to optimize system layouts for stray light performance.

* Work closely with opto-mechanical engineers to design and validate physical stray light mitigation hardware.

* Partner with material scientists to evaluate Bidirectional Scattering Distribution Functions (BSDF/BRDF), surface roughness, and specialized UV-resilient absorptive coatings/materials.

* Collaborate with Optical Systems Engineers to ensure stray light requirements are defined, met, and verified at the system level for ICF applications.

Qualifications

* Education:

B.S. or M.S. degree in Optical Engineering, Physics, or a closely related field.

* Experience:

5+ years of dedicated experience in stray light analysis and non-sequential optomechanical modeling.

* Expert-level proficiency in non-sequential optical design software, with a strong preference for FRED.

* Demonstrated experience writing scripts to automate optical analysis and process ray trace data.

* Strong understanding of stray light mitigation techniques, including the implementation of mechanical features (baffles, beam dumps) in optical models.

* Solid foundation in physical optics, scattering (BSDF/BRDF), and diffraction.

* Proven ability to work in a cross-collaborative environment with multi-disciplinary engineering teams.

* Must be a U.S. citizen or national, U.S. permanent resident (current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum.

Desired

* Ph.D. in Optical Engineering, Physics, or related field.

* 8+ years of experience in stray light analysis for high-energy laser systems or deep UV (DUV) applications.

* Experience with Laser Induced Damage Thresholds (LIDT) and material fluorescence in the DUV regime.

* Specific experience working on laser systems for Inertial Confinement Fusion (ICF) or similar high-fluence beam delivery systems.

* Familiarity with stray light measurement instrumentation (e.g., scatterometers) to correlate empirical…