| 摘要 |
PURPOSE:To make it possible to easily detect the coating film even a can is moving at a high speed, by irradiating the interior of a can to be measured with ultraviolet rays with a specific wavelength, and measuring and detecting the absorption degree thereof three-dimensionally and instantaneously. CONSTITUTION:For example, a detector is constituted of an irradiation lamp 1 emitting ultraviolet rays with a wavelength of 300nAm, a half mirror 2 arranged so as to be inclined at an angle of 45 deg. to an optical axis, detectors D1, D2, a convex lens 4, amplifiers A1, A2, an operator circuit A3, a control circuit A4 and a detector S. When a can 3 to be measured is irradiated with ultraviolet rays from the lamp 1, irregularily reflected light is absorbed, when internal coating is applied to the can, because of the internal coating and is not emitted to the outside of the can 3. When no internal coating is applied, light is emitted to the outside of the can 3 because of non-absorption and condensed by the convex lens 4 through the half mirror 2 and converted to electric signals by the detectors D1, D2 while these signals are operated and compared by the operator circuit A3 and the control circuit A4 to operate an alarm apparatus. Therefore, the coating film of the can be easily detected. |
