Katrašnik Jaka, Pernuš Franjo, Likar Boštjan
University of Ljubljana, Faculty of Electrical Engineering, Ljubljana, Slovenia.
Appl Opt. 2013 May 20;52(15):3526-37. doi: 10.1364/AO.52.003526.
The accuracy of the radiometric response of acousto-optic tunable filter (AOTF) hyperspectral imaging systems is crucial for obtaining reliable measurements. It is therefore important to know the radiometric response and noise characteristics of the hyperspectral imaging system used. A radiometric model of an AOTF hyperspectral imaging system composed of an imaging sensor radiometric model (CCD, CMOS, and sCMOS) and an AOTF light transmission model is proposed. Using the radiometric model, a method for obtaining the fixed pattern noise (FPN) of the imaging system by displacing and imaging an illuminated reference target is developed. Methods for estimating the temporal noise of the imaging system, using the photon transfer method, and for correcting FPN are also presented. Noise estimation and image restoration methods were tested on an AOTF hyperspectral imaging system. The results indicate that the developed methods can accurately calculate temporal and FPN, and can effectively correct the acquired images. After correction, the signal-to-noise ratio of the acquired images was shown to increase by 26%.
声光可调谐滤波器（AOTF）高光谱成像系统的辐射响应精度对于获得可靠测量结果至关重要。因此，了解所使用的高光谱成像系统的辐射响应和噪声特性非常重要。提出了一种由成像传感器辐射模型（CCD、CMOS和sCMOS）和AOTF光传输模型组成的AOTF高光谱成像系统的辐射模型。利用该辐射模型，开发了一种通过对照明参考目标进行位移和成像来获取成像系统固定模式噪声（FPN）的方法。还介绍了使用光子转移方法估计成像系统时间噪声以及校正FPN的方法。在AOTF高光谱成像系统上测试了噪声估计和图像恢复方法。结果表明，所开发的方法能够准确计算时间噪声和FPN，并能有效校正采集到的图像。校正后，采集到的图像的信噪比提高了26%。
