US 11,973,538 B2
Eye safe diverged beam optical wireless communications system
William J. Brown, Durham, NC (US); and Hannah Clark, Durham, NC (US)
Assigned to 8 RIVERS CAPITAL, LLC, Durham, NC (US)
Appl. No. 17/760,677
Filed by 8 RIVERS CAPITAL, LLC, Durham, NC (US)
PCT Filed Sep. 17, 2020, PCT No. PCT/IB2020/058684
§ 371(c)(1), (2) Date Mar. 15, 2022,
PCT Pub. No. WO2021/053583, PCT Pub. Date Mar. 25, 2021.
Claims priority of provisional application 62/901,391, filed on Sep. 17, 2019.
Prior Publication US 2022/0393769 A1, Dec. 8, 2022
Int. Cl. H04B 10/50 (2013.01); G02B 5/02 (2006.01); G02B 19/00 (2006.01); H04B 10/11 (2013.01)
CPC H04B 10/503 (2013.01) [G02B 5/02 (2013.01); G02B 19/0047 (2013.01); G02B 19/009 (2013.01); H04B 10/11 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A diverged beam optical transmitter comprising:
a laser source configured to emit a light beam;
one or more lenses;
a diffuser placed between the laser source and the one or more lenses, and configured to increase an intrinsic divergence of the light beam and to fill some portion of the one or more lenses such that the light beam is eye safe after the one or more lenses, wherein the diffuser is an active element configured to change a degree of diffusion in response to an input, and
one or both of:
(i) an additional passive diffuser between the active diffuser and the one or more lenses, and
(ii) wherein the active element is a mechanically movable element that substantially prevents transmission of light in its resting position.