A Multilevel Optical Anticounterfeiting System Based on Color Space‐Correlated Raman Spectroscopy of Diamond

Optical anticounterfeiting certifies the authenticity of goods using optical information coding units. A Raman tag with Raman peaks serving as copious optical information coding units is optimal for optical anticounterfeiting. However, complex manufacturing conditions, the use of toxic materials/pollutants, and the request for cross‐reference with fluorescence and/or Rayleigh scattering limit its actual application. Herein, these drawbacks are tackled by proposing the color space‐correlated Raman spectroscopy of diamonds, which are recognized as an extraordinary material in many respects. Specifically, diamond is utilized as a Raman tag because the 1332 cm−1 Raman peaks generate unlimited information coding states with excitation wavelengths and excitation powers. The diamond Raman spectra with excitation wavelength and excitation power in color space and grayscale space to access a 6D (R, G, B, Alpha, excitation wavelength, and excitation power) information coding space are swept. The design's implementation with a diamond is first showcased. Then, the corresponding information coding capacities in grayscale, color space and the dependencies of red, green, blue (RGB) color filters are investigated. Finally, a practical application of the method is proposed. This work opens up a new pathway for publicizing Raman‐based optical anticounterfeiting by an infinitely scalable information coding strategy with diamond photonics.