Fluorescent penetrant inspection sensor

Claim 1

A nondestructive testing apparatus for detecting flaws on a surface of a workpiece, the workpiece being treated with a substance which fluoresces in the presence of exciting radiation, the substance being trapped in flaws in the workpiece surface, said apparatus comprising: a light source for directing a beam of exciting radiation onto the surface of the workpiece; detector means for sensing radiation within a predetermined frequency range and generating an electrical signal representative thereof; a plurality of lenses positioned for receiving fluorescing radiation emitted from the surface in response to the exciting radiation, said lenses focusing said fluorescing radiation onto said detector means, said plurality of lenses being circumferentially arranged around the directed radiation beam; a plurality of light receiving means included in said radiation detector means, each of said lenses focusing radiation on at least one of said light receiving means; a radiation to electrical signal converter; and a plurality of light transmitting means, each of said light transmitting means coupled to one of said light receiving means for coupling said radiation to said converter; a light filter located between each of said plurality of lenses and said detector means for blocking reflected exciting radiation; processing means responsive to said fluorescing radiation for generating an indication of a flaw; and means for effecting movement of said directed beam of exciting radiation for radiating different locations on the workpiece surface, said movement means generating a signal representative of a location of the beam on the workpiece surface, said movement means including an oscillating deflecting mirror positioned to deflect the radiation beam from the light source onto said workpiece surface, said mirror effecting a scanning motion of said radiation beam, said processing means being responsive to said signal for providing data identifying the location of the flaw.

Claim 8

A method for detecting and locating flaws on the surface of a workpiece using a radiation source for generating a directed laser beam of exciting radiation and a radiation detector responsive to emitted radiation from the surface of the workpiece, said method comprising the steps of: (a) applying a fluorescent penetrant to the workpiece which seeps into flaws of the workpiece surface, the penetrant being of the type which fluoresces in response to impinging radiation; (b) orienting the workpiece in the radiation beam for exposure to the radiation beam; (c) defocusing the laser beam; (d) refocusing the beam onto the workpiece surface with a diameter of about four mils; (e) providing a signal representative of beam position on the workpiece surface; (f) focusing emitted radiation from the penetrant on the radiation detector; and (g) correlating the intensity of emitted radiation with the beam position signal for determining the presence and location of a flaw.

Claim 9

A method for detecting and locating flaws on the surface of a workpiece using a radiation source for generating a directed laser beam of exciting radiation and a radiation detector responsive to emitted radiation from the surface of the workpiece, said method comprising the steps of: (a) applying a fluorescent penetrant to the workpiece which seeps into flaws of the workpiece surface, the penetrant being of the type which fluoresces in response to impinging radiation; (b) orienting the workpiece in the radiation beam for exposure to the radiation beam; (c) defocusing the laser beam; (d) refocusing the beam onto the workpiece surface with a diameter of about four mils; (e) providing a signal representative of beam position on the workpiece surface; (f) focusing emitted radiation from the penetrant on the radiation detector; and (g) correlating the intensity of emitted radiation with the beam position signal for determining the presence and location of a flaw.