To provide improved scratch resistance while transmitting light in a plurality of wavelength ranges. A transmission member (20) includes a base material (30) that transmits far-infrared rays, and a first functional film (32) that is formed on the base material (30). Average transmittance of the transmission member (20) with respect to light at a wavelength from 8 μm to 12 μm is equal to or larger than 50%, and transmittance of the transmission member (20) with respect to light from a laser beam source that emits light in a wavelength range from 0.8 μm to 1.8 μm is equal to or larger than 80%. A refractive index of an outermost layer (34) of the first functional film (32) with respect to light from the laser beam source is equal to or larger than 1.7.
TRANSMISSION MEMBER
2025-01-23
Patent
Electronic Resource
English