Two-photon recording of microholograms in photopolymer materials with new cationic thioxanthone photoinitiators

摘要

We have demonstrated two-photon induced recording of the microholograms at an arbitrary point within thick (approx100 (mu)m) photopolymer material using photoinitiators on a basis of new cationic thioxanthone derivatives. Such material provides high values of refractive index change (DELTA)n velence 4.8 X 10~(-3), and holographic recording sensitivity S velence 1.2 cm/J. A nanosecond laser pulse at a wavelength of 532 nm was used for recording. For the selective on the depth reading of the microholograms the method of collinear heterodyning was applied.