Patent ID: 9494422
Filing Date: 2016-11-15
CPC Classification: G01B,G01N

Claim Text:
1. A lighting device for inspection, comprising: a surface light source that emits inspection light; a lens that is provided on a light axis of the inspection light emitted from the surface light source, the lens being a closest lens to the inspection object, and between an inspection object and the surface light source; and a first diaphragm that is provided between the surface light source and the lens, or between the lens and the inspection object, wherein positions of the surface light source and the lens with respect to the inspection object are set such that an image plane on which the surface light source is imaged in focus is present near the inspection object, a position of the first diaphragm with respect to the lens is set such that a central axis of an irradiation solid angle determined by the inspection light, which is incident on an outer edge part of the image plane, is parallel to the light axis, or is displaced from the light axis and tilted by a predetermined amount, and the inspection object has a convex inspection surface, the first diaphragm is arranged outside a focal point of the lens such that the central axis of the irradiation solid angle is tilted from an outer edge side toward a center side of the image plane.