Patent ID: 7187457
Filing Date: 2007-03-06
Classification: G01B

Abstract:
1. An apparatus for measuring sizes of articles comprising: a light projecting device for projecting light toward an article from one side of an article; a photo-sensor device arranged on the other side of the article and including a plurality of photo-detectors arranged in array in a first direction such that light projected from the light projecting device and impinging upon the photo-sensor device without being interrupted by the article is received by one or more photo-detectors; a driving device for reciprocally moving the light projecting device and photo-sensor device relative to the article in a second direction perpendicular to the first direction; a shifting device for shifting the photo-sensor device in the first direction into at least first and second positions which are mutually separated by a distance smaller than a pitch at which the photo-detectors are arranged in array; a control device for controlling the driving device and shifting device such that when the light projecting device and photo-sensor device are moved by the driving device in a forward direction, the photo-sensor device is in the first position and when the light projecting device and photo-sensor device are moved by the driving device in a backward direction, the photo-sensor device is in the second position; and a signal processing device for processing output signals generated from the photo-detectors under a control of a control signal supplied from the control device to measure size of the article with a resolution higher than the pitch at which the photo-detectors are arranged in array.