吡咯俘精酸酐的光致各向异性研究

Photoinduced Anisotropy in Pyrrylfulgide/PMMA Film

将有机光致变色化合物—吡咯取代俘精酸酐掺杂于PMMA中形成薄膜 在紫外光照射下 ,薄膜由无色态转换为呈色态 用 6 5 0nm线偏振激光照射薄膜 ,在由呈色态转变为无色态时产生光致各向异性 对 6 33nm的探测光具有正单轴晶体特性 ,光轴方向平行于激发光振动方向 ,光致二向色性率 (D⊥ -D∥)可达 0 .2 ,光致双折射率 (n∥ -n⊥)可达 2× 1 0 - 3 实验还测量了光致各向异性与曝光量的特性曲线 ,发现最佳曝光量为 1 3～ 2 0J/cm2 ,理论分析了其原因

A new organic photochromic compound pyrrylfulgide is prepared as a film in PMMA. Under UV light, the film converts from the bleach state into colored state. After the irradiation of linearly polarized 650 nm light, the film shows the characteristic of the positive uniaxial crystal at 633 nm, the optical axis is parallel to the vibration direction of the exciting light beam, and the photoindused dichroism (D ⊥-D ∥) is above 0.2, and the photoinduced birefringence (n ∥-n ⊥) is 2×10 -3 . From the changing curve of the photoinduced anisotropy with the exposal, the best exposure scale 13～20 J/cm 2 was found, and the reason was theoretically analyzed. These results have given the experimental data for the fulgides to be used in the optical information processing.