| 摘要 |
An apparatus for detecting an edge of a transparent substrate includes a light source provided on a rear side of the edge of the transparent substrate, a first polarizer provided between the transparent substrate and the light source and arranged to convert light from the light source to linearly polarized light, a light receiving unit provided on a front side of the edge of the transparent substrate, and a second polarizer provided between the transparent substrate and the light receiving unit, and having a polarization axis that is perpendicular or substantially perpendicular to a polarization axis of the first polarizer. The light receiving unit is configured to observe, through the second polarizer, the linearly polarized light that is converted by the first polarizer and is transmitted through the edge of the transparent substrate, the linearly polarized light that is converted by the first polarizer and passes outside the transparent substrate, and emitted light that is converted by the first polarizer, and is propagated through inside of the transparent substrate and emitted from a side surface of the edge of the transparent substrate.
|
