2019 journal article

Trade-off between field-of-view and resolution in the thermal-integrated argus II system

Translational Vision Science and Technology, 8(4).

co-author countries: Israel 🇮🇱 United States of America 🇺🇸
author keywords: ultralow vision; visual prosthesis; field-of-view; spatial resolution; rehabilitation
Source: ORCID
Added: November 4, 2022

To investigate the effect of a wider field-of-view (FOV) of a retinal prosthesis on the users' performance in locating objects.One female and four male subjects who were blind due to end-stage retinitis pigmentosa and had been implanted with the Argus II retinal prosthesis participated (aged 63.4 ± 15.4). Thermal imaging was captured by an external sensor and converted to electrical stimulation to the retina. Subjects were asked to localize and to reach for heat-emitting objects using two different FOV mappings: a normal 1:1 mapping (no zoom) that provided 18° × 11° FOV and a 3:1 mapping (zoom out) that provided 49° × 35° FOV. Their accuracy and response time were recorded.Subjects were less accurate and took longer to complete the tasks with zoom out compared to no zoom. Localization accuracy decreased from 83% (95% confidence interval, 75%, 90%) with no zoom to 76% (67%, 83%) with zoom out (P = 0.07). Reaching accuracy differed between the two mappings only in one subject. Response time increased by 43% for the localization task (24%, 66%; P < 0.001) and by 20% for the reaching task (0%, 45%; P = 0.055).Argus II wearers can efficiently find heat-emitting objects with the default 18° × 11° FOV of the current Argus II. For spatial localization, a higher spatial resolution may be preferred over a wider FOV.Understanding the trade-off between FOV and spatial resolution in retinal prosthesis users can guide device optimization.