在双层介电薄膜结构双液体变焦透镜模型的基础上, 分析了透镜焦距与外加电压、双层介电薄膜的介电常量、薄膜厚度等参量的关系.并以降低双液体变焦透镜驱动电压为目的, 选择了相对介电常量较高的五氧化二钽薄膜作为内层介电层, 相对介电常量较低的防水层为外层介电层, 分析了双层介电薄膜的厚度以及厚度的匹配对双液体变焦透镜的变焦范围和驱动电压的影响, 在保证一定的变焦范围并尽可能降低透镜驱动电压情况下获得最佳透镜工艺参量.模拟结果表明: 疏水层薄膜厚度比高介电层薄膜厚度小很多时, 双液体变焦透镜可实现低压驱动, 且双液体变焦透镜在一定变焦范围内所需驱动电压可下降到10 V以下, 而疏水层薄膜厚度与高介电层薄膜厚度相当或高于高介电层薄膜厚度都不能有效利用高介电薄膜的高介电性能来降低双液体变焦透镜的驱动电压.

A relationship between the focal length of the double-liquid lens and other parameters such as the applied voltage, the dielectric constant of the double-layer dielectric film and the film thickness etc. was analyzed based on the cylindrical double-liquid lens model with double-layer dielectric film. And the tantalum pentoxide film with a high relative dielectric constant as an inter-layer dielectric layer and a relatively low dielectric constant for the outer dielectric layer which is a waterproof layer, were used to reduce the driving voltage of double-liquid variable-focus lens. The effects of the thickness of two dielectric films and the thickness matching relationship between them were described on the variable-focus range and the driving voltage of the double-liquid lens. The optimum film parameters were obtained on the condition of minimizing the drive voltage of the lens at a certain variable-focus range. Simulation results show that double-liquid lens can be driven by relatively low voltage when the waterproof film thickness is much thinner than that of the high dielectric constant thin film. Within a certain variable-focus range, the driving voltage of the double-liquid variable-focus lens can drop to 10 volts. But double-liquid lens will not make efficient use of the high dielectric property of the tantalum pentoxide film, if the thickness of waterproof film is equivalent to or higher than that of the high dielectric constant thin film.