| 摘要 |
<p>A light detection device comprising a first detecting portion 4 to detect fluorescence from a first detection position A on a conveyor path 115 along which a sheet P is conveyed; a second detecting portion 5 to detect afterglow from a second detection position B on the conveyor path 115 along which the sheet P is conveyed; a lighting portion 3 to apply excitation light over a range including the first detection position A and not including the second detection position B; a first reference member 10 to emit reference light toward the first detecting portion 4, the first reference member 10 including fluorescent material which emits fluorescence by being excited by the lighting portion 3; a second reference member 11 to emit reference light toward the second detecting portion 5 when the sheet P is present at the second detection position B, the reference light not influencing a result of detection by the second detecting portion 5; and a correction controller 9 to correct a result of detection by the first detecting portion 4 based on the reference light detected by the first detecting portion 4 and to correct a result of detection by the second detecting portion 5 based on the reference light detected by the second detecting portion 5.</p> |
