Highly efficient NIR light distribution for imaging based intrusion detection
US9606229B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2014 |
| Grant date | Mar 28, 2017 |
| Priority date | — |
| Expiry date | Aug 25, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J5/0806
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus is provided that includes a near infrared (NIR) light emitting diode (LED) having a predominant axis of NIR light transmission from the NIR LED and a lens that disperses NIR light received from the NIR LED with respect to first and second planes, the lens having an air to lens light entry boundary where light from the NIR LED enters a surface of the lens and a lens to air boundary where the light exits the lens in each of the first and second planes, wherein an intersection formed by the second plane with the surface is a line that is concave on each side of the predominant axis, and wherein a radius of the air to lens light entry boundary of the line successively increases over each span of a predetermined number of degrees progressing outwards along the line from the predominant axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.