陈一超+胡文刚+武东生+何永强+张冬晓+张瑜

摘要：

为了得到更符合人眼视觉特性的彩色夜视图像，依据RGB彩色理论模型，提出一种基于滤光片分谱作用的三波段彩色夜视方法。根据微光夜视系统成像理论，计算微光夜视系统的视距一般表达式。以典型场景作为探测目标，研究引入滤光片前后微光夜视系统的视距变化率，其中蓝光波段的滤光片引入使视距下降到引入前的15%。基于视距理论分析及色度学原理，提出了提高滤光片的透过率、拓宽滤光片的透过波段、融合图像加入全波图像的三个改进方法。以此制备了三片滤光片，并进行了彩色夜视实验。实验表明，提出的改进方法得到的彩色夜视图像在熵和标准方差两个指标上均优于原始微光图像和传统融合方法得到的结果，且与人眼主观感受一致。

关键词：

夜视； 视距估算； 彩色微光夜视； 滤光片

中图分类号： O 439文献标志码： Adoi： 10.3969/j.issn.1005-5630.2016.04.007

Abstract：

In order to obtain color night vision images，which are more in line with the characteristics of the human eye，tri-band color night vision technology is put forward based on RBG color model.The technique is the use of sub-spectral filter effect.Visual range is calculated based on night vision imaging systems theory.The change rate of visual range，before and after the introduction of filter，is calculated in a typical scenario.The result shows that visual range which is after the introduction of filter falls to 15% compared to before.Considering analysis above and color theory，three methods have been proposed to improve：Increasing the transmittance of the filter in the band needed；Broaden the band of the filter；Full-wave image fusion.Three filters are produced according to the improved methods.Experiment is taken by these three filters.Fused images which are experimentally obtained，are better than original low-light images by the objective evaluation，on the two indicators that are entropy and average variance.The results are also consistent with the observed effect of the human eye.The experimental results show the methods are effective.

Keywords：

night vision； visual range evaluation； color low-night vision； filter

引言

微光夜视系统借助于光电成像器件可在低照度条件下观察景物。微光夜视装备具有体积小、造价低[1]、成像细节清晰、图像自然等优点，在军事领域得到广泛应用。目前所装备的微光夜视器材产生的都是单色图像，单色图像具有信噪比低、立体感差等缺点，在军事应用中易受到伪装迷惑。为了提高夜视图像对比度，使人眼能够更快速地识别目标，利用人眼对彩色更为敏感的视觉特性[2]，可以通过假彩色编码以及将不同波段的成像进行融合得到彩色夜视图像[3]。……