With a standard stand-mounted CCTV, a page of printed text lies on a movable x-y platform under a video camera. A technique, called page navigation, must thus be used to reveal successive parts of the text on the display screen. When reading highly magnified text on a screen, only a portion of the line of text is visible at any moment. One important limitation of EVES is a reduced field of view with high levels of magnification, an issue which has received considerable attention in the context of low vision reading. Common commercially-available EVES are closed-circuit televisions (CCTVs). A recent survey indicated that most low vision patients express an interest in image processing technology that could be implemented for television viewing and for computer use. Įlectronic Vision Enhancement Systems (EVES) have a great potential to improve perceptual performance of low vision patients : in addition to magnification, they can provide many kinds of visual enhancements. To achieve this goal, magnifying optical and/or electronic aids are commonly prescribed to help maintain the ability to read, even though magnification never restores reading speed to the level observed without CFL. One major goal of people with CFL is to improve their ability to read text. Reading speed is a key performance measure that has been extensively investigated in low vision reading. This scotoma in the center of the visual field dramatically disrupts reading performance. This does not alter our adherence to PLOS ONE policies on sharing data and materials.Īge-related Macular Degeneration (AMD), a severe maculopathy, is the most common cause of low vision and often causes dramatic Central Field Loss (CFL) among elderly people who are therefore constrained to use eccentric viewing. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Ĭompeting interests: Carlos Aguilar’s (CA) Ph.D. grant from Essilor International ( ) to CA. įunding: This work was supported by a Ph. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: All data files are available from the figshare database at. Received: JAccepted: MaPublished: April 5, 2017Ĭopyright: © 2017 Aguilar, Castet. González-Méijome, Universidade do Minho, PORTUGAL This proof of concept study suggests that the principles underlying the gaze-controlled enhanced system might be further developed and fruitfully incorporated in different kinds of EVES for low vision reading.Ĭitation: Aguilar C, Castet E (2017) Evaluation of a gaze-controlled vision enhancement system for reading in visually impaired people. In addition, learning curves were similar in the three conditions. Importantly, reading speed results did not show any significant difference between the three systems. All subjects were able to use condition 1 and they found it slightly more comfortable to use than condition 2 (and similar to condition 3). Reading speed was measured and constituted the main dependent variable to compare the three conditions. Ten healthy subjects with a gaze-contingent scotoma read aloud sentences from a French newspaper in nine experimental one-hour sessions. A gaze-contingent artificial 10° scotoma (a mask continuously displayed in real time on the screen at the gaze location) was used in the three conditions in order to simulate macular degeneration. The three conditions were implemented on the same computer to remove differences that might have been induced by dissimilar equipment. In these two conditions, magnification was uniformly applied to the whole text without any possibility to specifically select a region of interest. Two other conditions were implemented that mimicked commercially available advanced systems known as CCTV (closed-circuit television systems)-conditions 2 and 3. We have developed and implemented a real-time gaze-controlled system whose goal is to optimize the possibility of magnifying a portion of text while maintaining global viewing of the other portions of the text (condition 1). Due to the restricted field of view of EVES, the need for magnification is conflicting with the need to navigate through text (panning). The flexibility of Electronic Vision Enhancement Systems (EVES) offers several ways of magnifying text. People with low vision, especially those with Central Field Loss (CFL), need magnification to read.
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