Analysis Study of Spectral and Thermal Properties of Near-Infrared Blocking Ophthalmic lenses

Abstract

Near-infrared (NIR) blocking ophthalmic lenses are commercially available, but data supporting their properties and performance are difficult to find. This study aims to provide objective data through clinical results of NIR blocking ophthalmic lenses and to verify color reproducibility and thermal properties and performance according to the influence of NIR for practical use. Near-infrared blocking spectacle lenses (NIBSL) (polymerized, coated) and other types of spectacle lenses (clear, tinted) were manufactured and classified into 0, 2, and 3 grades (10 types) of luminous transmittance. The near-infrared environment was configured and the color reproducibility evaluation factors, such as sharpness (MTF50), chromatic aberration (CA), and color accuracy (△E), were compared in an outdoor environment (1000 lux). The thermal properties were analyzed by observing the temperature changes on the surface of the spectacle lens and pig skin in real time in environments of 36℃ and 60℃. NIBSL showed no difference in object discrimination and color recognition compared to other types of spectacle lenses. In terms of thermal characteristics, NIBSL showed a smaller increase in lens surface temperature, and the pig skin temperature was maintained lower, showing excellent insulation performance. These results suggest that NIBSL can be used in everyday life without problems in visual ability and color reproducibility, and may be useful in protecting eyes from the thermal hazards of near-infrared light. In addition, we presented a new research method that improves the accuracy and reliability of optical functional spectacle lenses in the near-infrared region (harmful to humans).