Peli E, Siegmund W P
Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts 02114, USA.
J Opt Soc Am A Opt Image Sci Vis. 1995 Oct;12(10):2274-85. doi: 10.1364/josaa.12.002274.
We describe fiber-optic stand magnifiers specifically designed for use as low-vision reading aids. Application of this technology results in better optical and ergonomic properties. The fiber-optic magnifiers (tapers) provide bright, uniformly illuminated, distortion-free images. The reading material can be scanned without the user's having to bend directly over the magnifier. One can further increase the scanning field by slanting the taper to tilt the image toward the observer. Tilting the upper face of the taper by cutting the smaller lower face on a bias is shown to increase the scanning range substantially and to provide better control of illumination. The scanning range of such tilted tapers is approximately double that of the equivalent lens magnifiers. To increase the contrast transfer through the magnifiers, we have developed lower-resolution tapers with an increased core-to-cladding ratio. The increase in contrast transfer is reported for representative tapers. The lower-resolution design is also helpful in reducing the manufacturing cost of taper magnifiers.
我们描述了专门设计用作低视力阅读辅助工具的光纤支架放大镜。这项技术的应用带来了更好的光学和人体工程学特性。光纤放大镜（光锥）能提供明亮、均匀照明且无畸变的图像。阅读材料可以进行扫描，而使用者无需直接俯身于放大镜上方。通过倾斜光锥使图像向观察者倾斜，还可以进一步扩大扫描范围。通过在斜面上切割较小的下表面来倾斜光锥的上表面，结果显示可以大幅增加扫描范围并更好地控制照明。这种倾斜光锥的扫描范围大约是等效透镜放大镜的两倍。为了提高通过放大镜的对比度传递，我们开发了具有更高芯包比的低分辨率光锥。报告了代表性光锥对比度传递的增加情况。低分辨率设计还有助于降低光锥放大镜的制造成本。
