Passive ultraviolet (UV) imaging is a potential way to detect thin oil film on water surface due to the high reflectivity of oil film under UV bands. This study conducted an outfield imaging experiment on oil film under the UV bands at 300 nm, 310 nm, and 330 nm. The obtained images were visually compared and quantitatively analyzed using imaging quality index (IQI). The experimental results indicated that the UV images obtained under 300 nm are not able to distinguish between oil film and clean water; those obtained under 310 nm achieve high contrast between oil film and clean water, but low average gray value; those obtained under 330 nm have high IQI and thus may be the optimal wavelength for UV imaging of oil film on water surface. This study provides a guidance to the choices of bands for the oil film detection using passive UV imaging method.

由于油膜在紫外波段下的高反射率，被动紫外（UV）成像是检测水面薄油膜的一种潜在方法。本研究对 300 nm、310 nm 和 330 nm 紫外波段下的油膜进行了外场成像实验。使用成像质量指数（IQI）对获得的图像进行视觉比较和定量分析。实验结果表明，在300 nm下获得的UV图像无法区分油膜和清水；在310nm下获得的油膜与清水的对比度较高，但平均灰度值较低；在330 nm下获得的具有较高的IQI，因此可能是水面油膜UV成像的最佳波长。本研究为被动紫外成像法检测油膜的波段选择提供了指导。