Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

RETRO-REFLECTOR

IP.com Disclosure Number: IPCOM000024432D
Original Publication Date: 1980-Aug-31
Included in the Prior Art Database: 2004-Apr-02
Document File: 1 page(s) / 66K

Publishing Venue

Xerox Disclosure Journal

Abstract

A retro-reflector, a segment of which is as shown in the figure, consists of a closely packed array of hemispherical surfaces 2 on one side of a sheet 3 of transparent material. On the other side of the sheet is an array of concentric spherical surf aces 4, each spherical surface concentric with a hemispherical surface. The spherical surfaces are coated with a reflective material such as aluminum or silver. Surfaces 2 and 4 have a radius of R1 and R2, respectively; index of refraction n2 of the sheet 3 is higher than nl.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 89% of the total text.

Page 1 of 1

XEROX DISCLOSURE JOURNAL

RETRO-R EFLEC TOR 350/97 C1. U.S. Proposed Paul L. Faust Classification

Int. C1. G02b 5/12

A retro-reflector, a segment of which is as shown in the figure, consists of a closely packed array of hemispherical surfaces 2 on one side of a sheet 3 of transparent material. On the other side of the sheet is an array of concentric spherical surf aces 4, each spherical surface concentric with a hemispherical surface. The spherical surfaces are coated with a reflective material such as
aluminum or silver. Surfaces 2 and 4 have a radius of R1 and R2, respectively; index of refraction n2 of the sheet 3 is higher than nl.

A ray 6 entering from the right is refracted at surface 2A, reflected at surface 4A and exits at surface 2B. If the n2, ratio of R1 to R2 is appropriately chosen for the two indices of refraction (n, and n ), the exit ray is parallel to the entering ray. The ratio of R1 to R2 may be compu i! ed from paraxial theory.

The array can be made by a molding process as follows: A closely packed array of rigid spheres (e.g., glass beads) of desired radius is overlain with a sheet of material whose thickness is R2-Rl. The sheet is either thermally or chemically plasticized. With the sheet in its plastic state, an appropriate hydrostatic pressure is applied from the side opposite the spheres until the sheet conforms to and forms a bond with the spheres. The sheet is made rigid by thermal or chemical means and the side opposite the spheres, now...