Photonic crystals market was valued at USD 14.24 million in 2026 and is projected to reach USD 46.25 million by 2036, recording a CAGR of 12.5% during 2027–2036. Asia-Pacific was the largest region in 2026 at an estimated ~37% share. The market centers on engineered one-dimensional periodic dielectric stacks and two-dimensional photonic crystal microstructured optical fibres used to control waveguide confinement, dispersion, polarization and light-matter interaction.