NEAR INFRARED RAY CUT-OFF EYEGLASSES, FACE PROTECTION TOOL, AND NEAR INFRARED RAY CUT-OFF FILTER

摘要

Provided are near infrared ray cut-off eyeglasses, a face protection tool and a near infrared ray cut-off filter, which enable the cut off of near infrared ray at lower cost compared with a case in which gold (Au) is used, while allowing proper transmission of light of a visible region. An ion-gun-type ion plating device (200) is used. Titanium (Ti) is set as a cathode (250) and, at the same time, an argon (Ar) gas and a nitrogen gas that serves as a reactive gas are used to form a thin titanium nitride film on an almost transparent base (240). The flow rates of the reactive gas and others are adjusted, so that near infrared ray cut-off eyeglasses which have a transmittance of light of a visible region of 8% or more and a transmittance of light of a near infrared region of 30% or less can be produced.