On-Screen Deconvolution to Facilitate Computer Access for Users with Visual Impairments Involving Higher-Order Wavefront Aberrations

通过图形用户界面与计算机成功交互隐含地需要不失真地感知计算机屏幕上显示的图像。对于有严重和不规则视力限制的人来说，这是一个问题，无法通过眼镜或隐形眼镜等传统机制纠正。在这个项目中，PI将探索让计算机生成经过修改的显示以纠正圆锥角膜、透明边缘变性、Terrien边缘退化以及相关的屈光障碍等情况的可能性，这些疾病以不对称和不规则的方式扭曲了眼睛感知的图像。由这些条件引入的失真的不规则性通过需要在眼睛的波前像差(WA)函数的Zernike多项式近似中包括更高阶(即2)项来捕捉，该函数表示通过眼睛的光学组件(角膜、晶状体)的图像的失真。图像处理和验光方面的最新进展，以及为实时应用增加计算能力的持续承诺，使得有可能设想一种计算机系统，该计算机系统在给定其用户的视觉能力的适当特征的情况下，将以互补的方式产生与他/她的视觉限制相匹配的显示，从而克服用户的视觉问题。此外，能够准确描述一个人的Wa的仪器现在已经可以商业化了。PI和他的团队将使用从个人的Wa获得的点扩展函数(PSF)对计算机屏幕上显示的图像进行预补偿(通过去卷积)，以便考虑PSF的个人不会感觉到它们的失真。广泛的影响：这个项目将导致新的辅助技术的设计，这反过来很可能导致工具造福于广大民众。由于将有大量学生参与该项目，而且PI的机构是全国少数几个拥有博士水平综合课程的少数民族机构之一，因此也有望对教育产生重大影响。去卷积工作有可能在技术和社会层面产生广泛影响，因为它构成了一种新的方法，通过数字而不是光学手段对用于视觉矫正目的的图像进行补偿，并考虑到传统解决方案中被忽视的高阶视损伤可能会影响多达700万患有极不规则屈光不正的美国人。

Successful interaction with a computer through a graphical user interface implicitly requires the undistorted perception of the images displayed on the computer screen. This is a problem for individuals with severe and irregular visual limitations that cannot be corrected through traditional mechanisms such as eyeglasses or contact lenses. In this project the PI will explore the possibility of having the computer generate modified displays to correct conditions such as keratoconus, pellucid marginal degeneration, Terrien's marginal degeneration, and related refraction disorders that distort the images perceived by the eye in asymmetrical and irregular ways. The irregularity of the distortion introduced by these conditions is captured by the need to include higher-order (i.e., 2) terms in the Zernike polynomial approximation of the eye's wavefront aberration (WA) function, which represents the distortion of images through the optical components of the eye (cornea, lens). Recent advances in image processing and optometry, as well as the continued promise of increasing computing power for real-time applications, make it possible to envision a computer system that, given the proper characterization of the visual capabilities of its user, will generate a display that matches his/her vision limitations in a complementary way, thus overcoming the user's vision problem. Furthermore, instruments capable of accurately characterizing a person's WA are now commercially available. The PI and his team will use the point-spread function (PSF), obtained from a person's WA, to pre-compensate (by deconvolution) the images shown on the computer screen, so that they are perceived undistorted by the individual whose PSF is considered.Broader Impacts: This project will lead to the design of novel assistive technologies, which in turn may well lead to tools that benefit the population at large. A substantial impact on education is also to be expected, due to the large number of students who will participate in the project and in light of the fact that the PI's institution is one of the few minority institutions in the nation with comprehensive programs through the PhD level. The deconvolution work has the potential for broad impact in both technical and societal dimensions, in that it constitutes a novel approach to compensation of images for visual correction purposes via digital rather than optical means, and in consideration of estimates that higher-order visual impairment neglected in traditional solutions may affect as many as 7,000,000 Americans who have excessively irregular refractive errors.