水下沉潜油有源偏振高光谱成像探测方法研究

Compared with traditional marine oil spills, submerged oil contamination possesses strong concealment and deception, which makes the monitoring and handling of it very difficult. Especially those spilled within offshore waters, they are more harmful to the marine environment as well as human production and life. In order to meet the strong technical requirement of submerged oil monitoring, this project intends to develop an underwater active hyperspectral detection method by combining the hyperspectral detection technology with the detection and identification requirements of submerged oil. Aiming at the polarization characteristics of laser-induced fluorescence and elastic scattering/reflection signals of submerged oil, the applicability and stability of staring hyperspectral imaging acquisition mode using Liquid Crystal Variable Retarder (LCVR) and filter wheel for underwater target detection are systematically measured, and effects of the range-gated and polarization discrimination techniques are comprehensively compared in underwater active detection interference suppression, imaging contrast and clarity improvement as well as the effective detection range of submerged objects. Then, a detection and recognition method of submerged oil based on the polarization differences within the fusion information of spectra and image is established to effectively improve the detection and recognition ability of submerged oil contamination to compensate the shortcomings of existing technologies in the detection of them.

相较传统海洋溢油，沉潜油具有较强的隐蔽性和欺骗性，给溢油事故的监测监视和应对处置造成很大的难度，对海洋环境和人类生产生活的危害性高于其他类型的污染物，尤其是那些发生在近岸水域的沉潜油污染。针对沉潜油监视监测的技术需求，本课题拟将高光谱成像探测技术与有源水下主动成像探测技术有机结合，发展一种面向沉潜油水下探测的有源偏振高光谱探测方法。针对水下沉潜油的激光诱导荧光和弹性散射/反射信号的偏振特性开展针对性的实验研究，系统衡量采用液晶相位延迟器LCVR配合滤光片轮的凝视型高光谱成像采集模式应用于水下目标的适用性和稳定性，综合比较距离选通、偏振辨别等技术在抑制水下有源探测干扰，提高成像对比度和清晰度，提升水下目标物有效探测距离方面的效果，建立基于水下偏振图谱信息差异的沉潜油探测识别方法，以显著提升针对沉潜溢油污染的探测辨别能力，有效弥补现有技术短板。

相较传统的水面溢油，沉潜油具有较强的隐蔽性和欺骗性，给溢油事故的监视监测和应对处置造成很大的难度，对海洋环境和人类生产生活的危害性高于其它类型的污染物，尤其是那些发生在近岸水域的沉潜油污染。针对沉潜油监视监测的需求，本课题将高光谱成像探测技术与水下沉潜油探测识别需求相结合，发展了一种水下沉潜油有源高光谱探测方法。为了针对水下沉潜油的诱导荧光和弹性反射信号的偏振特性开展针对性实验研究，研制了面向水下目标物的有源多光谱偏振成像仪和大功率多波长水下激光光源，针对采用沥青渣油、添加重晶石的重油稠油样品、岩石、贝壳、海沙等制备的模拟水下样品开展激光诱导荧光和宽带反射光谱成像探测实验，将水下可变反射率标准板与模拟底质样品置于相同成像距离进行成像观测，通过特定通道对应区域灰度图像的平均灰度比值获得目标物场景的特定波段的光谱反射率，通过像素配准后特定区域多波段荧光图像灰度比值完成诱导荧光相对效率定标，完成了诱导荧光区域和宽带反射光谱区域的伪色彩渲染；基于诱导荧光图像和弹性反射图像数据发展了水下沉潜油加权识别方法，显著提高了水下沉潜油疑似目标的检测识别能力。