超光谱成像仪图像均匀性校正

Correction of image uniformity for imaging spectrometer

为获得高质量新型超光谱成像仪图像,根据新型超光谱成像仪图像特点,对其图像均匀性校正进行研究。利用转台旋转模拟超光谱成像仪对地面推扫,对景物成像获得超光谱成像仪三维数据;采用太阳作为新型超光谱成像仪图像均匀性校正光源,应用相应校正系数对超光谱成像仪的数据进行处理。结果表明:所采用校正方法对新型超光谱成像仪具有很好校正效果,同时也验证了新型成像光谱仪具有较高成像质量;单像元校正时间为2×10-6s,大数据量图像校正需较长时间;利用太阳照射漫反射板作为扩展源对亮度均匀物体图像进行校正,校正均匀性小于4%。

To obtain a high quality image from the new type imaging spectrometer,the uniformity correction method for the image was studied according to the characteristics of the image.The new type imaging spectrometer was placed on the rotation stage to simulate the pushbroom of the imaging spectrometer,then the image was got by the imaging spectrometer.The sun was used as the uniformity correction source of the image for the imaging spectrometer,and the data cubic was progressed by the software.Experimental results indicate that high quality image is obtained by using this method,and it also verifies the high performance of the new type imaging spectrometer.The correction time for one pixel is 2 × 10-6 s,but much time is needed for large volume of images in the image uniformity correction.Moreover,a diffuser was used as a extended source to correct the image with uniform luminance,and the correction uniformity is less than 4%.