An edge position detecting apparatus includes a light emitting device, a detecting device, and a calculating circuit. The light emitting device includes a plurality of light sources with different emission wavelengths. The light emitting device irradiates a conveyed object with linear light along a width direction of the conveyed object, the width direction being perpendicular to a conveying direction of the conveyed object. The detecting device detects, at a plurality of positions in the width direction of the conveyed object, intensity of reflected light of light emitted by the light emitting device. The calculating circuit calculates, based on a detection result of the detecting device, a position of an edge of the conveyed object in the width direction.

An edge position detecting apparatus includes a light emitting device, a detecting device, and a calculating circuit. The light emitting device includes a plurality of light sources with different emission wavelengths. The light emitting device irradiates a conveyed object with linear light along a width direction of the conveyed object, the width direction being perpendicular to a conveying direction of the conveyed object. The detecting device detects, at a plurality of positions in the width direction of the conveyed object, intensity of reflected light of light emitted by the light emitting device. The calculating circuit calculates, based on a detection result of the detecting device, a position of an edge of the conveyed object in the width direction.

A defect inspection device includes: a radiation source configured to emit an electromagnetic wave radially to a separator roll; a TDI sensor configured to detect the electromagnetic wave which has passed through the separator roll; and a moving mechanism configured to move an inspection region of the separator roll with a distance kept substantially constant between the radiation source and the separator roll and with a distance kept substantially constant between the radiation source and the TDI sensor.