Loading patent…
AssigneeErwin Sick Gesellschaft mit Beschrankter Haftung, Optik-Elektronic
InventorsSiegfried Mankel, Klaus Ostertag, Heinz Schreyer
Estimating the term…
Optical fault seeking apparatus for material webs uses an optical scanning device to scan the material webs point by point line by line. The optical scanning device consists of a laser light source (17) which projects a light beam via a micro-objective (19), a cylindrical lens (20), and a further objective onto a mirror wheel arrangement (14) which is located substantially at the focus of a strip-like concave mirror (23). A light beam (24) is produced in the image space of the strip-like concave mirror (23) and generates a scanning light bead in a scanning plane through which the material web passes. The mirror wheel arrangement (14) has at least first and second alternately operating types of mirror surfaces which serve to alternately project light beads of different size and/or shape onto the material web thus enabling different types of fault to be reliably detected. The different types of scanning light bead are produced either by different curvatures of the faces (15) and (17) of the mirror wheel arrangement (14) or by the use of other optical means alone or in combination with differently shaped faces of the mirror wheel. Certain embodiments operate using two mirror wheels in tandem.
Optical fault seeking apparatus for material webs comprising an optical scanning device including mirror wheel means and a light source for projecting beams of light onto a material web moving in a scanning plane of the apparatus to form beads of light thereon and for scanning said beads of light cyclically across the scanning plane transverse to the direction of movement of the material web, at least one light receiving device arranged to pick up light from the light beads formed on the web and to guide this light to at least one associated photoelectric converter for producing an electrical signal corresponding to the light received, and wherein said mirror wheel means has at least first and second alternately operating types of mirror surfaces of which the first projects a first light bead having a first characteristic onto said material web and the second projects a second light bead having a second different characteristic onto said material web.
Dependencies are inferred from the claim text.