Optically active materials and articles and systems in which they may be used

Patent metadata

Field	Value
Publication number	US-10417534-B2
Application number	US-201715437880-A
Country	US
Kind code	B2
Filing date	Feb 21, 2017
Priority date	Dec 15, 2008
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

Another embodiment of the present application relates to a method of manufacturing an optically active article, comprising: obtaining an optically active sheeting; and positioning an infrared-reflecting material on the optically active sheeting to form a pattern. The optically active article may be, for example, a license plate.

First claim

The invention claimed is:

1. A retroreflective article, comprising:
a multilayer optical film covering at least a portion of a retroreflective sheeting, which retroreflects incident light; and
wherein the multilayer optical film exhibits a relatively high reflectance for light within a first spectral range and a relatively low reflectance and high transmission for light within a second spectral range, wherein the multilayer optical film forms a pattern that can be read by a sensor;
wherein the first spectral range is between about 700 nm to about 1100 nm and the second spectral range is between about 400 nm to about 700 nm.

2. The retroreflective article of claim 1 , wherein the retroreflective article is one of a license plate and a traffic sign.

3. The retroreflective article of claim 1 , wherein the pattern includes one of a machine readable information, bar code, character, graphic and image.

4. The retroreflective article of claim 1 , wherein the retroreflective sheeting is one of beaded sheeting or prismatic sheeting.

5. The retroreflective article of claim 1 , wherein the multilayer optical film is attached to the retroreflective sheeting by one of lamination, bonding, mechanical fixation and use of an adhesive.

Assignees

• 3M Innovative Properties Co

Inventors

• Smithson Robert L W
• Biernath Rolf W

Classifications

• B60R13/10 Primary

  Registration, licensing, or like devices · CPC title

• G06V10/143

  Sensing or illuminating at different wavelengths · CPC title

• G02B5/0816

  Multilayer mirrors, i.e. having two or more reflecting layers (G02B5/0883, G02B5/0891 take precedence) · CPC title

• Y10T156/10

  Methods of surface bonding and/or assembly therefor · CPC title

• G02B5/136

  plural reflecting elements forming part of a unitary body (G02B5/124 takes precedence) · CPC title