Abstract A surface inspecting apparatus is provided and includes a light source which illuminates the surface of an object to be inspected. A slit plate having a plurality of slits of different shape which determine the field of vision for the object is provided and is arranged in the path of the reflected light from the object to be inspected. A plurality of photo-electric conversion devices are provided for converting the reflected light from the object to be inspected which passes through the slits. Further means are provided for scanning the field of vision. By detecting the change of the light quantity of the reflected light from the object to be inspected which passes through the slits by the photo-electric conversion devices, it can be readily determined whether defects in the object to be inspected exist or not. Also by comparing the output of each of the photo-electric conversion devices, the shape of any defect can be determined.
A surface inspecting apparatus comprising: means for illuminating the surface of an object to be inspected; a slit plate having a plurality of slits of different shape, said slit plate rigidly positioned in the path of the reflected light from the object to be inspected, and slits determining the field of vision for the object to be inspected; a plurality of photo-electric conversion devices corresponding in number to said plurality of slits, each of said photoelectric devices positioned to receive the reflected light passing through one of said slits for converting the reflected light from the field of vision of the object to be inspected into a corresponding electrical signal; and means for comparing said electrical signals from said plurality of photo-electric conversion devices whereby the nature of any defect detected thereby can be determined.
Claim 2
Dependent Claim
135 words
A surface inspecting apparatus comprising: means for illuminating the surface of an object to be inspected; a slit plate having a plurality of slits of different shape, said slit plate rigidly positioned in the path of the reflected light from the object to be inspected, and slits determining the field of vision for the object to be inspected; a plurality of photo-electric conversion devices corresponding in number to said plurality of slits, each of said photoelectric devices positioned to receive the reflected light passing through one of said slits for converting the reflected light from the field of vision of the object to be inspected into a corresponding electrical signal; and means for comparing said electrical signals from said plurality of photo-electric conversion devices whereby the nature of any defect detected thereby can be determined.
Claim 3
Dependent Claim
24 words
A surface inspecting apparatus according to claim 1, wherein said slit plate comprises a plurality of polygon slits of different sizes from each other.
Claim 4
Dependent Claim
28 words
A surface inspecting apparatus according to claim 2, in which said plurality of slits are composed of a square one, a rectangular one and a rectangular strip one.
Claim 5
Dependent Claim
25 words
A surface inspecting apparatus according to claim 1, in which said slit plate comprises a plurality of circular slits of different sizes from each other.
Claim 6
Dependent Claim
18 words
A surface inspecting apparatus according to claim 1, which further includes means for scanning the field of vision.
Claim 7
Dependent Claim
61 words
A surface inspecting apparatus according to claim 1, further includes means for processing an output signal of the photo-electric conversion devices, said means for processing having a preamplifier for amplifying said output of said photo-electric conversion devices and a wave height discriminator circuit for discriminating between a signal due to a defect in the object to be inspected and other signals.