Red-cyan complementary color laser illumination (C2LI) for perceptually enhanced sensing and imaging of structurally colored samples

We introduce complementary color laser illumination (C²LI), a non-digital method that maximizes chromatic contrast sensitivity using spectrally engineered laser light. By leveraging non-linearities in human color vision, C²LI is shown to be effective for enhanced imaging of structurally colored samples, including sensors, biological specimens, and defective semiconductor chips. Our results show that C²LI significantly improves contrast perception, offering promising applications in biomedical imaging, diagnostics, and materials analysis.