Threshold for Millimeter-Wave (60 GHz)-Induced Ocular Injury

Millimeter waves (MMW) absorbed by skin or cornea may induce damage by heat. We have developed a 60 GHz MMW exposure-induced eye injury model that reproducibly presents the extent of such ocular injury, including its clinical process and healing process. Findings by the model suggested an ocular damage threshold for an exposure dose of about 60 GHz 200–300 mW/cm2 for 6 min. Using the probit model, DD50, defined as the dose to cause ocular damage with 50% probability, was estimated to be 233 mW/cm2. A novel finding was that exposure of 60 GHz 400 mW/cm2 to a closed eyelid for 6 min not only damaged the eyelid (including the palpebral conjunctiva), but the eyeball surface beneath (the bulbar conjunctiva and cornea) it.