Quiescent circle and arc generator

• Main Author: PENNEY; CARL M
• Format: Patent
• Language: English
• Published: 13.01.1987
• Edition: 4
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PERFORMING OPERATIONS; PHYSICS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

The optical properties of circular prisms, which are also known as axicons, are utilized in optical systems that generate one or more quiescent, steady in time, sharply focused circular and arc-shaped patterns of light. A laser beam incident on the circular prism is deviated by the prism effect and the emerging beam focused onto a target surface by a spherical lens or zoom lens; the radius of the circle is conveniently adjusted. Systems with stationary optics are described to efficiently form two concentric, uniform circles, or two offset circular or approximately circular arcs, from input beams derived from one or two lasers. These structured light patterns are used in tracking an edge or groove, for instance to locate the workpiece joint in robotic arc welding.