Because the core performance and testability of our optical particle counters are determined at the interface of optics, photonics, and the detection signal chain, the role carries explicit design authority over system architecture, requirements, and verification adequacy, and is empowered to make and arbitrate cross-functional technical trade-off decisions across the optical, electrical, firmware, software, and mechanical disciplines. Hold clear decision rights at the system level: decide system architecture, interface definitions, and verification adequacy; recommend trade-offs that affect cost, schedule, and scope to program and portfolio leadership; and resolve cross-discipline technical disputes through the engineering leadership chain.