GB1523095A - Method for the optical measurement of distances - Google Patents

Abstract

1523095 Measuring dimensions COMMISSARIAT A L'ENERGIE ATOMIQUE 4 May 1977 [7 May 1976] 18708/77 Heading G1A To determine the width of an object, an image of it is formed by a microscope, and the image is scanned by a camera so as to form a visual display on a screen; two parallel lines are superimposed on the screen and are moved until they coincide with opposite edges of the displayed object. The circuitry for generating and moving the lines also produces numbers representing their position, and these numbers are used to compute the line separation, and hence the object width. If desired, each line may be replaced by a pair of lines separated by the permissible tolerance on the width of the object, so that the operator can see if the object is within desired limits or not. Various ways of processing the number associated with the lines are disclosed; for example the number for each line can be entered into a respective counter, each counter then being counted down to zero and the time between the moments that the counters reach zero represents separation, Fig. 2 (not shown). Alternatively, each number may be stored and compared with an increasing count, the difference in time between the moments at which that count equals the numbers being representative of the separations, Fig. 3 (not shown). Suitable time measuring circuitry is given, Fig. 4 (not shown), as well as a four line embodiment for tolerance display, Fig. 5 (not shown).