Experimental Physicist - Infrared Detection Systems

About the Company

Quell is a high-growth British defence and security AI technology start-up developing solutions to counter drone, vehicle, and human threats across the military, civilian and critical national infrastructure sectors.

Based near Cambridge, we are seeking exceptional Experimental Physicists to design and develop advanced optical systems used in monitoring, tracking, and computer vision applications. This is a hands-on, multidisciplinary role working across the full product lifecycle—from concept and design through to prototyping, testing, and product release.

Key Responsibilities

• Designing, modelling, and validating optical systems including lenses, mirrors, mounts, and electro-optic sensors
• Developing optical solutions for high-performance monitoring, tracking, and computer vision applications (VIS, NIR, FIR)
• Using ray-tracing and simulation tools (e.g., OpticStudio or equivalent) to model and optimise optical components
• Selecting suitable materials and components for high-performance optical assemblies
• Collaborating closely with multidisciplinary teams including engineers, technicians, and product managers
• Developing machine-vision systems to meet demanding technical and reliability requirements
• Supporting prototype builds, system integration, testing, and validation
• Managing workstreams independently and ensuring timely delivery of project milestones

Requirements

• Degree in Optical Engineering, Physics, Electrical Engineering, or related field (Master’s/PhD preferred)
• Experience designing optical systems, particularly in electro-optics or machine vision
• Strong understanding of optical design principles including ray tracing, lens design, and simulation
• Familiarity with optical test methods and performance validation
• Knowledge of opto-mechanics, electronics, image processing, and electro-optical systems
• Proficiency with ray-tracing software (e.g., OpticStudio or similar)
• Strong organisational skills and ability to manage tasks independently
• Comfortable working onsite in the Cambridge area

Please note: While you do not need active clearance to apply, you must be eligible to undergo UK Security Check (SC) clearance vetting if selected.

Desirable

• Experience working with laser systems
• Knowledge of infrared optics (NIR/FIR)
• Experience working in multidisciplinary or agile engineering environments

Details

• Location: North Uttlesford / Greater Cambridge area, on-site
• Five days a week on-site (ie: this is not a hybrid role)
• Full UK driving licence required. If this isn't held, candidates will need to commit to obtaining within 6 months of their start date
• Applicants must be fully eligible to work in the UK without restriction, time limit, or the need for current or future sponsorship.

To Apply

Please apply via LinkedIn with your CV and a short covering note, including your salary expectations and availability.