| 摘要 |
PURPOSE:To detect surely foreign matter by irradiating excitation light to an object to be inspected, shutting off the excitation light reflected from said objest and detecting only the fluorescence from the foreign matter. CONSTITUTION:The light from a lamp 15 is irradiated via a condenser lens 16, a half mirror 18 and an objective lens 19 to an object 2 to be inspected. The detection of the light from the object 2 is accomplished by a photomultiplier tube 23 via the lens 19, the mirror 18, a slit 20 and a condenser lens 21. A visible light filter 22 is placed in the midway of the optical path for detection and only the wavelength region of the fluorescence emitted from foreign matter is detected. The object 2 is moved by motors 5, 6 during inspection and the presence or absence of the foreign matter over the entire surface of the object to be inspected is detected. The positional coordinates of the foreign matter on the object 2 are recorded in a recording part 13 for defect address. |
