Apparatus for detecting particles on a glass surface and a method thereof

A glass surface's particle detecting method for detecting whether particles existing on a surface of glass which is being transferred are attached to an upper side or a lower side of a glass substrate, comprising the steps of:

• a first step of irradiating a laser beam on an upper surface of glass in a first direction perpendicular to a second direction in which a glass substrate moves, wherein the laser beam is irradiated from one upper side of the glass substrate to other upper side of the glass substrate, and receiving a beam diffused by the particles to output the beam as a video image;
• and
• a second step of irradiating a laser beam on a lower surface of glass in a first direction perpendicular to a second direction in which the glass substrate moves, wherein the laser beam is irradiated from one lower side of the glass substrate to other lower side of the glass substrate, and receiving a beam diffused by the particles to output the beam as a video image.