The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 06, 2004
Filed:
Oct. 04, 2001
Laurent Potin, Bordeaux, FR;
Thales Avionics S.A., Velizy Villacoublay, FR;
Abstract
Visors for helmets are generally of spherical shape and of constant thickness, and articulated to the side walls of a helmet at the level of the forehead, about an axis of articulation passing through the center of their sphere. Thus shaped and mounted, they are seen off axis by a helmet wearer leading to optical distortions for him caused by diffraction effects on their internal and external faces. Visors with shapes modified to minimize the optical distortions perceived by a helmet wearer are proposed here. A first type of modification consists of a relative pivoting, in the vertical plane, of one of the faces of the visor with respect to the other and of a slight reduction in the ratio of the radius of curvature of the outer face of the visor to that of the inner face of the visor compared to the usual concentric bispherical visor. A second type of modification consists of adopting one or two aspherical surfaces of particular shape. A third type of modification consists of using a holographic diffraction mask fixed to one of the faces of the visor.