Detection device and image forming apparatus for reducing a cavity effect

摘要

A detection device includes: a detection member that includes an emission member emitting a beam toward a direction of a transportation path and a beam receiving member receiving a reflected beam reflected from a medium; a transmissive member that is provided to allow a regular reflected beam of the beam reflected from the medium to be obliquely incident thereto, and through which the beam emitted from the emission member is transmitted; and a multiple-layered antireflective film that is provided on the transmissive member, the antireflective film being formed such that a maximum value of reflectivity of a first incident beam incident at the same angle as an incident angle of the regular reflected beam becomes smaller than a maximum value of reflectivity of a second incident beam incident in the direction perpendicular to the transmissive member within a visible light wavelength range.

主权项

1. A detection device comprising:
a detection member that includes an emission member emitting a beam toward a direction of a transportation path transporting a medium thereon and a beam receiving member receiving a reflected beam emitted from the emission member and reflected from the medium transported along the transportation path, and that detects at least one of an image formed on the medium transported along the transportation path, or the medium; a transmissive member that is provided to allow a regular reflected beam of the beam reflected from the medium to be obliquely incident thereto, and through which the beam emitted from the emission member is transmitted; and a multiple-layered antireflective film that is provided on the transmissive member, the antireflective film being formed such that a maximum value of reflectivity of a first incident beam incident at the same angle as an incident angle of the reflected beam is smaller than a maximum value of reflectivity of a second incident beam incident in the direction perpendicular to the transmissive member within a visible light wavelength range.