Fisheye lens designs and their relative （鱼眼镜头的设计和他们的相对的）.pdf

Fisheye lens designs and their relative performance a b James “Jay” Kumler , Martin Bauer aCoastal Optical Systems, 4480 South Tiffany Drive, West Palm Beach, FL 33407 bInternet Pictures Corporation, 1009 Commerce Park Drive, Oak Ridge, TN 37830 ABSTRACT New panoramic and immersive digital imaging developments have generated increased interest in high performance fisheye camera lenses suitable for 35 mm single lens reflex (SLR) cameras. Special concerns for such applications are the uniformity of illumination and radial image mapping. Because two hemispherical images are digitally stitched together to form a complete 360-degree x 180-degree image, the performance of the lens at the 90 degree (preferably more than 90 degree) edge of the fisheye image is just as important as the center of the image. Lateral color, high order distortion (edge compression) and severe drop-off of illumination at the full field become obvious image defects and cause seams in the immersive image. Fisheye lens designs have widely varying relative illumination and distortion across the hemispherical field of view of the lens. After describing the contributing factors to relative illumination, we survey a collection of fisheye designs and compare their illumination performance, radial mapping and lateral color. A new method of measuring relative illumination and radial mapping in the laboratory is described and results on commercially available fish-eye lenses are presented. Keywords: Fisheye lenses, optical design, relative illumination, distortion testing. 1. DE