Patent ID: 8448937

Claim:
A medium supplying apparatus comprising: a loading rack having a plurality of sheet-shaped media stacked therein; a separation mechanism that separates one medium at a time from the plurality of media and transports the medium; an irradiation unit that emits light onto a surface of the medium which is to be separated, the irradiation unit including: a first irradiation section that emits a first irradiation beam onto the surface of the medium at a first incidence angle; and a second irradiation section that emits a second irradiation beam onto the surface of the medium at a second incidence angle, which is different from the first incidence angle, the first irradiation beam and the second irradiation beam being selectively emitted; a light receiving unit that receives the reflected light reflected from the surface of the medium, the light emitted by the irradiation unit, and detects an intensity of the reflected light, the light receiving unit including: a first specularly-reflected light receiving section that receives the specularly-reflected light component of the reflected light at the time of emission of the first irradiation beam and detects an intensity of the specularly-reflected light; a second specularly-reflected light receiving section that receives the specularly-reflected light component of the reflected light at the time of emission of the second irradiation beam and detects an intensity of the specularly-reflected light; and a diffusely-reflected light receiving unit that receives a diffusely-reflected light component of the reflected light and detects an intensity of the diffusely-reflected light component; and a controller connected to the separation mechanism, the irradiation unit, and the light receiving unit, wherein based on a ratio of the diffusely-reflected light intensity at the time of emission of the first irradiation beam to the specularly-reflected light intensity detected by the first specularly-reflected light receiving section and a ratio of the diffusely-reflected light intensity at the time of emission of the second irradiation beam to the specularly-reflected light intensity detected by the second specularly-reflected light receiving section, the controller controls the separation mechanism to set a separating force for separating a next medium.