Programmable Photonics-Empowered Ultralow-Cost Photonic Device Metrology

Characterizing the spectral responses of photonic devices (PDs) is foundational to their development, optimization, and deployment. Conventional PD metrology relies on bulky, expensive instruments such as tunable laser sources (TLS) or optical spectrum analyzers (OSAs), which typically cost tens to hundreds of thousands of dollars, demand stringent environmental controls, and confine high-fidelity characterization to specialized laboratories—creating a critical bottleneck for photonic technology scaling. Here, we report a transformative solution: a compact, ultralow-cost spectral characterization platform based on a CMOS-compatible programmable photonic integrated circuit (PPIC) paired with a low-cost broadband source (e.g., LED). Critically, the monolithic PPIC incorporates on-chip photodetectors and is fully packaged both electrically and optically, significantly relaxing environmental operating constraints. This integration, combined with wafer-scale manufacturing, enables a per-chip cost of <$10—two to three orders of magnitude lower than existing integrated spectral tools. The approach is validated on various PDs, including a tunable optical filter, a broad amplified spontaneous emission, a waveshaper with complex spectra, photonic integrated circuits with both interferometric and resonant devices etc. Beyond laboratory metrology, it enables new applications such as in-line photonic manufacturing testing, field-deployable sensing, and portable spectroscopy—establishing a new paradigm for low-cost, scalable optical measurement.