US 2015/0316492 A1 · Apparatus and Method of Detecting Foreign Material on Upper Surface of Transparent Substrate Using Polarized Light

Abstract

Provided are an apparatus and a method of detecting a foreign material capable of detecting only a foreign material on a surface of a substrate except for a foreign material on a lower surface of the substrate in a manufacturing process of a transparent substrate passing light therethrough, such as a glass substrate used in a flat panel display (FPD) such as a liquid crystal display (LCD), an organic light emitting diode (OLED), a plasma display panel (PDP), a sapphire wafer used in some of semiconductors, or the like, and in a pattern forming process in a manufacturing process of the FPD and the semiconductor using the transparent substrate.

Claims10

Dependent claims

An apparatus for detecting a foreign material on an upper surface of a transparent substrate using polarized light, comprising:

a light source part irradiating light to the transparent substrate;
a first detecting part detecting P-polarized light in scattered light of foreign materials attached onto the transparent substrate by the irradiated light;
a second detecting part detecting S-polarized light in the scattered light of the foreign materials attached onto the transparent substrate by the irradiated light;
and
a controlling part comparing a brightness of the P-polarized light detected by the first detecting part and a brightness of the S-polarized light detected by the second detecting part with each other to distinguish the foreign material attached onto the upper surface of the transparent substrate and a foreign material attached onto a lower surface of the transparent substrate from each other.

2 more elements

A method of detecting a foreign material on an upper surface of a transparent substrate using polarized light, comprising:

irradiating light having a predetermined incident angle to the transparent substrate;
detecting P-polarized light in scattered light of foreign materials attached onto the transparent substrate by the irradiated light;
detecting S-polarized light in the scattered light of the foreign materials attached onto the transparent substrate by the irradiated light;
comparing a brightness of the P-polarized light and a brightness of the S-polarized light with each other to distinguish the foreign material attached onto the upper surface of the transparent substrate and a foreign material attached onto a lower surface of the transparent substrate from each other;
and
removing the foreign material attached onto the lower surface of the transparent substrate.

3 more elements

Dependencies are inferred from the claim text.

Apparatus and Method of Detecting Foreign Material on Upper Surface of Transparent Substrate Using Polarized Light

Life of this patent

Apparatus and Method of Detecting Foreign Material on Upper Surface of Transparent Substrate Using Polarized Light

Life of this patent

Abstract

Claims10