COMPUTER-BASED ASSESSMENT OF VISUAL-ACUIT Y - TECHNICAL REALIZATION

Testing of visual acuity for distant vision can be computerized by usi ng monitor screens to present optotypes. Because of the limited spatia l resolution of conventional monitors, measurement of visual acuity fo r near vision is not possible. This paper describes a new computer-aid ed method for the measurement of both near and distant visual acuity. Our approach to the assessment of visual acuity for near vision is bas ed on a recently developed liquid crystal display (a screen, LCD) meas uring 10.5 mm x 15 mm. The LCD permits the presentation of optotypes f or the measurement of visual acuity between 0.063 and 1.25 at a viewin g distance of 40 cm (near/distant). The presentation of optotypes for the assessment of the acuity of distant vision uses a standard 17 '' m onitor that permits visual acuity figures of between 0.032 and 1.6 to be assessed.