Development of a Low-Cost Ophthalmic Slit Lamp Prototype for Community Eye Clinics in Ondo State

Ophthalmic slit lamp examination is fundamental to anterior segment eye disease diagnosis, but the high cost of commercial slit lamps limits their availability at community eye clinics and mission hospitals in Ondo State. This study develops a low-cost ophthalmic slit lamp prototype for use at community eye clinics in Ondo State. The prototype employs a high-brightness white LED light source, an adjustable slit aperture mechanism fabricated from aluminium sheet metal, an acrylic cylindrical lens for slit beam formation, and a 10x binocular magnifier optical system mounted on a joystick-controlled chin-rest assembly. The illumination and observation systems are arranged at standard biomicroscopy variable angle geometry. Illumination intensity is adjustable through a pulse-width modulated dimmer circuit. A smartphone camera adapter attachment allows documentation of anterior segment findings via a compatible smartphone camera. Optical bench testing confirmed slit width adjustment from 0.2 to 8 millimetres and illumination beam angulation range of forty degrees on each side. Total fabrication cost excluding the smartphone camera was under forty thousand naira, compared to the minimum two hundred thousand naira cost of the lowest-priced commercial alternative. A clinical usability evaluation by two ophthalmologists at Ondo State Specialist Hospital, Akure, confirmed the prototype provided adequate anterior segment visualization for detection of conjunctival lesions, corneal opacities, and iris abnormalities in fifteen patient examinations. Image quality was rated as acceptable for clinical documentation purposes. The study recommends further refinement of the objective lens system and field clinical testing at community clinics. Keywords: slit lamp, ophthalmic device, low-cost prototype, community eye clinic, Ondo State.