VCSELid

VCSELid is a term used to describe identification technologies that use vertical-cavity surface-emitting lasers (VCSELs) to produce distinctive optical signatures for authentication and tracking. The concept encompasses both intrinsic approaches based on the physical properties of a VCSEL and external tagging schemes that illuminate objects with coded light patterns readable by a dedicated detector.

In practice, VCSELid can rely on intrinsic PUF-like variability in a VCSEL's emission, including tiny wavelength offsets, polarization purity, and speckle-like mode patterns that are difficult to clone. Alternatively, it can use encoded light patterns emitted by VCSEL arrays, where each element is calibrated to produce a unique, time-varying signature. Information can be embedded in spectral, temporal, or polarization domains, and detected by a sensitive photodetector or spectrometer.

Applications include device authentication, anti-counterfeiting, secure access control, and supply-chain tagging. A verifier compares the observed signature against a stored profile to grant permission or track provenance. VCSELid is compatible with existing silicon photonics and can be integrated into embedded systems, wearables, or smart cards.

Challenges include sensitivity to temperature and aging, which can alter emission characteristics; the need for robust detectors; privacy concerns; and the lack of standardized protocols. Ongoing research focuses on stabilizing signals, calibrating under varying conditions, and developing compact readers to enable reliable operation across diverse environments.