Patent ID: 9690200
Date: 2017-06-27
CPC Classifications: G03F

Claim:
1. An optical apparatus, comprising: a stage configured to support a substrate; a first optical system configured to provide a first light onto the substrate; a gantry configured to support the first optical system to transfer the first optical system above the stage; and a second optical system disposed between the gantry and the stage to detect displacement of the first optical system, wherein the second optical system comprises: a beam source configured to generate a second light that is different from the first light; a sensor array configured to receive the second light provided to the first optical system to detect the displacement of the first optical system; a beam splitter connected to the gantry, disposed adjacent to the first optical system, and configured to split the second light into an aiming beam and a transmission beam; and a beam reflector disposed at an end portion of the first optical system to provide a reflected beam induced from the aiming beam to the sensor array, wherein the aiming beam is parallel to the first optical system and the transmission beam is parallel to the gantry.