Method of forming relief surfaces
US5384571A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 1993 |
| Grant date | Jan 24, 1995 |
| Priority date | — |
| Expiry date | Jan 11, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B27/0018
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A ultrablack article made of a resin containing light absorbing pigments or dyes and its method of manufacture. The surface of the article is provided with light reflecting projections that cause incident light to reflect from the sides of such projections at least twice and preferably at least three times before reflecting from the articles surface. The vast majority of the incident light is thereby transmitted into the article where it is absorbed. The projections are advantageously conical, pyramidal or ridge shaped. The total incident light that reflects from the surface and from the interior of the article is not greater than 0.5%. The surface can be made by applying cone or pyramid shaped light beams to photoresist stepwise to make cones and pyramids and by scanning to make ridges. Means are provided to transfer such surfaces to more suitable resins and to do so continuously.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.