用亚甲蓝敏化的重铬酸铵明胶全息图的工艺研究

Processing of holograms recorded in methylene blue sensitized gelatin

研究了用亚甲蓝敏化的重铬酸铵明胶（ＭＢＤＣＧ）全息图的工艺，提出了提高脱水温度并将急剧脱水过程改为逐步脱水过程的制作方法，提高了衍射光栅的角度（波长）灵敏度，避免了在制作过程中明胶发生霜现的现象。研究了明胶中重铬酸铵和亚甲蓝的浓度、曝光量和脱水温度对全息图像衍射效率的影响。实验结果能较好地符合由Ｋｏｇｅｌｎｉｋ的耦合波理论导出的理论值。

An improved method in making methylene blue sensitized dichromated gelatin (MBDCG) holograms is presented. The dehydration temperature was raised to increase the angle sensitivity. Instead of rapid dehydration a multistep dehydration method was developed, in which the concentration of isopropyl alcohol was increased gradually in each step so as to avoid the milky in the gelatin during the processing. The effects of the concentrations of ammonium dichromate and methylene blue, the exposure and the dehydration temperature on the diffraction efficiency were studied. The specification data of the methylene blue sensitized dichromated gelatin (MBDCG) holograms with high quality were also reported.