The Smith-Kettlewell Technical File, edited by William Gerrey (WA6NPC), was a publication by and for blind and visually-impaired electronics professionals and enthusiasts. It was published by the Smith-Kettlewell Eye Research Institute from Fall 1980, through Spring 1998 and was at various times available in Braille, large print, audio cassette, and 5-1/4" floppy diskette.
Although The Smith-Kettlewell Technical File is no longer in active publication, we offer this online archive as a resource of both current and historical value.
While many of the articles about devices and techniques remain…
Eccentric power refractors need to be calibrated for accommodation and gaze position for individual participants. Calibration however can be time consuming. We look at different conditions in which calibration is necessary or preferable.
This project is now completed. Please see the Publication section for results.
Crowding increases with eccentricity, and is most readily observed in the periphery. During natural, active vision however, central vision plays an important role. Measures of critical distance to estimate crowding are difficult in central vision, as these distances are small. Any overlap of flankers with the target may create an overlay masking confound. The crowding factor method avoids this issue by simultaneously modulating target size and flanker distance and using a ratio to compare crowded to uncrowded conditions. This method was developed and applied in the periphery (Petrov &…
There is continuing debate as to whether smooth pursuit relies on the foveation of a moving target, especially when the target is compact. Previous studies have shown that gaze is placed on the center-of-mass of a target during saccadic eye movements. This research aims to understand whether eye placement is similarly centered during smooth pursuit and whether foveation is necessary for pursuing a small stimulus.