Instrument for checking the surface condition of the ground, particularly of roads, motorways, airport runways, pavements, terraces

摘要

This instrument consists of a metal tube (10) intended to be laid vertically on the ground via a shoe (11) and of an optical system made up of eyepiece (14) mounted in the upper opening of the tube (10), of an objective (15) housed in the tube (10) and of a total reflection prism (16) located in the tube at an opening (13). By looking into the tube through the eyepiece (14), an enlarged right image of the surface of the ground can be seen at a grazing angle of incidence. IMAGE