About the Role We are seeking a senior Director of Optical Science & Systems to lead optical system architecture, scientific development, and technical execution across R&D and customer-facing projects. This is a hands-on leadership role at the core of our technology. You will define optical architectures, shape scientific vision and IP, engage directly with customers and partners, and work closely with executive management to translate strategy into robust, differentiated optical sensing solutions. As a deep-tech startup, this role combines scientific leadership, system-level thinking, and practical laboratory work. The ideal candidate is equally comfortable defining long-term technical direction and aligning an optical setup in the lab when needed. This position is expected to evolve over time, with a clear path toward executive technical leadership (e.g. CTO or Chief Scientist) as the company grows, provided the candidate has the right aptitude and competencies required. Key Responsibilities Optical System Design & Scientific Leadership •\tAct as the company’s lead authority for optical systems across internal R&D and customer projects. •\tDefine, design, simulate, prototype, and validate advanced optical and optoelectronic systems. •\tProvide expert guidance on optical architecture, tolerancing, performance trade-offs, and system integration. •\tMentor and technically support engineers and scientists working on optical sensing systems. Client-Facing Technical Leadership •\tServe as the primary optical and scientific expert in customer and partner interactions. •\tLead technical discussions, feasibility studies, and solution definition with industrial and research partners. •\tClearly communicate complex optical concepts to technical and non-technical stakeholders. •\tSupport business development through technical input, demonstrations, and proposal contributions. Project & Program Ownership •\tLead and coordinate a portfolio of internal R&D, customer-funded, and publicly funded projects. •\tDefine technical objectives, milestones, and deliverables; ensure execution on time and within scope. •\tWork closely with multidisciplinary teams (MEMS, electronics, software, data, management). Intellectual Property & Innovation •\tDrive IP generation and strategy in optics and sensing systems. •\tLead invention disclosures and support patent drafting and prosecution. •\tIdentify and protect key innovations aligned with long-term technology and product roadmaps. Strategy & Company Development •\tWork closely with the CEO and Chief Scientist to shape scientific vision, technology roadmap, and product strategy. •\tContribute to decisions on R&D priorities, resource allocation, and long-term platform evolution. •\tRepresent the company’s technical capabilities externally when required. Experimental & Laboratory Work •\tPerform hands-on laboratory work when needed, including optical setup, alignment, testing, and performance characterization. •\tSupport the transition from prototype to demonstrator and early production concepts. Leadership •\tDemonstrates strong interpersonal maturity, including the ability to influence without authority, build trust across technical and commercial stakeholders, and communicate complex scientific trade-offs with clarity and credibility. Exhibits the judgment, humility, and collaborative mindset required to evolve into a company-wide technical leader and trusted executive partner as the organization scales. Required Qualifications •\tPhD or MSc in Physics, Optics, Photonics, or a closely related field. •\tStrong background in optical system design and development. •\tProven experience leading complex, multidisciplinary R&D projects. •\tExperience in client-facing technical roles. •\tFamiliarity with IP generation and patent processes. •\tAbility to work independently, take technical ownership, and operate effectively in a startup environment. •\tProven ability to produce high-quality technical documentation and to translate complex technical results into clear, actionable insights for diverse audiences, including non-technical stakeholders. •\tComfortable executing across the full spectrum of activities, including leadership interactions, client engagement, and direct hands-on work in the optics laboratory. •\tFluent English; French is a strong advantage. Nice to Have •\tExperience with infrared systems (NIR/MIR), imaging, or spectroscopy. •\tExperience in startups or small, technology-driven companies. •\tExposure to MEMS-based or highly integrated sensing platforms. What We Offer •\tA senior, high-impact role with real influence on technology, IP, and strategy. •\tHands-on involvement in cutting-edge MEMS-based infrared sensing technology. •\tClose collaboration with executive leadership. •\tA flexible, technically ambitious startup environment. •\tCompetitive compensation based on experience. Why Join 4K-MEMS? •\tWork on cutting-edge MEMS-based infrared sensing technology with real industrial and societal impact. •\tJoin a small, highly skilled team where individual contributions have visible impact on the company. •\tExperience a deep-tech startup environment combining rapid experimentation, system-level problem solving, and application-driven development. If you are passionate about bringing technology to market and excel in a fast-paced, collaborative environment, we encourage you to apply. 4K-MEMS is an equal opportunities employer. We value diverse backgrounds, experiences, and perspectives, and believe they strengthen our team and our technology.