Surface inspection method and surface inspection device
First Claim
1. A surface inspection method for projecting a laser beam to an inspection surface and for scanning and detecting foreign objects or the like on the inspection surface, comprising a step of being had a required number of detecting regions by a photodetector against a projecting site of said laser beam, a step of receiving a detection light at said photodetector so that a detection light intensity is varied between said detecting regions, a step of acquiring a required number of output signals with different detection light intensities on an inspection site, and a step of selecting an output signal which is an unsaturated output signal and has the highest value among the required number of output signals as a surface detection signal.
1 Assignment
0 Petitions
Accused Products
Abstract
A surface inspection method for projecting a laser beam to an inspection surface and for scanning and detecting foreign objects or the like on the inspection surface, comprising a step of being had a required number of detecting regions by a photodetector against a projecting site of the laser beam, a step of receiving a detection light at the photodetector so that a detection light intensity is varied between the detecting regions, a step of acquiring a required number of output signals with different detection light intensities on an inspection site, and a step of selecting an output signal which is an unsaturated output signal and has the highest value among the required number of output signals as a surface detection signal.
-
Citations
8 Claims
- 1. A surface inspection method for projecting a laser beam to an inspection surface and for scanning and detecting foreign objects or the like on the inspection surface, comprising a step of being had a required number of detecting regions by a photodetector against a projecting site of said laser beam, a step of receiving a detection light at said photodetector so that a detection light intensity is varied between said detecting regions, a step of acquiring a required number of output signals with different detection light intensities on an inspection site, and a step of selecting an output signal which is an unsaturated output signal and has the highest value among the required number of output signals as a surface detection signal.
- 5. A surface inspection device, comprising an inspection light projecting system for projecting a laser beam to an inspection surface, a scattering light receiving system for detecting scattering lights, and an arithmetic operation unit for performing calculation to detect foreign objects or the like based on scattering light detection output of said scattering light receiving system, wherein said scattering light receiving system has a required number of detecting regions and detects detection lights so that the scattering light intensities to receive the detection light are varied between the detecting regions, and said arithmetic operation unit selects an unsaturated scattering light detecting output with the highest value among a plurality of scattering light detecting output obtained at the same site as a surface inspection signal, and foreign objects or the like are inspected based on the surface inspection signal.
Specification