Lens for a warning light
US6481873B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 13, 2001 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Jul 13, 2021 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21S43/26
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A convex lens for a warning light is provided with a plurality of prism-shaped prismatic elements projecting from the lens concave inner surface. The configuration and angular orientation of each prismatic element is selected to compensate for the curvature of the lens so that light refracted by each prismatic element emerges from the lens outer surface at substantially equivalent angles relative to an optical axis of the light. A preferred embodiment of the lens includes a matrix of prismatic elements that refract light incident on planar surfaces of the prismatic elements to an angle of 45° relative to an optical axis of the light. Each prismatic element also includes a convex radius at the convergence of the two refractive surfaces and concave radii at the junction of the planar surfaces with the inner surface of the lens. Light incident on these concave and convex surfaces is refracted along a range of angles to fill in the radiation pattern produced by the lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.