Boyd J E, Trentler T J, Wahi R K, Vega-Cantu Y I, Colvin V L
Appl Opt. 2000 May 10;39(14):2353-8. doi: 10.1364/ao.39.002353.
An important issue in developing applications for photopolymers in holography is the effect of film thickness on recording properties. Now it is possible to create these samples with a much wider range of thickness (d = 20-1400 mum) than was previously available. We exploit these recent advances in photopolymer processing to systematically evaluate how the dynamic range of a photopolymer depends on its thickness. The results illustrate that sample performance increases linearly with thickness as predicted by standard models of volume holography. However, above a critical thickness sample performance degrades, and the angular response of recorded plane-wave holograms shows evidence of grating curvature. These distortions are likely the result of photopolymer shrinkage, which in thicker samples occurs in a nonuniform fashion. This problem limits the performance of these photopolymers and is likely to be an issue for any photopolymer that undergoes comparable polymerization shrinkage.
在开发用于全息术的光聚合物应用时，一个重要问题是薄膜厚度对记录特性的影响。现在能够制造出厚度范围（d = 20 - 1400微米）比以前更宽的这些样品。我们利用光聚合物加工方面的这些最新进展，系统地评估光聚合物的动态范围如何取决于其厚度。结果表明，正如体积全息术的标准模型所预测的那样，样品性能随厚度呈线性增加。然而，超过临界厚度时，样品性能会下降，并且记录的平面波光全息图的角度响应显示出光栅曲率的迹象。这些畸变可能是光聚合物收缩的结果，在较厚的样品中，这种收缩以不均匀的方式发生。这个问题限制了这些光聚合物的性能，并且对于任何经历类似聚合收缩的光聚合物来说都可能是一个问题。
