US 11,909,224 B2
Photovoltaic cell for laser beam power detection
Ortal Alpert, Ness Ziona (IL); Ori Refael Mor, Tel Aviv (IL); Lior Golan, Ramat Gan (IL); Ran Sagi, Tel Aviv (IL); and Eyal Conforti, Tel Aviv (IL)
Assigned to Wi-Charge Ltd., Rehovot (IL)
Appl. No. 17/440,809
Filed by Wi-Charge Ltd., Rehovot (IL)
PCT Filed Mar. 20, 2020, PCT No. PCT/IL2020/050336
§ 371(c)(1), (2) Date Sep. 20, 2021,
PCT Pub. No. WO2020/188576, PCT Pub. Date Sep. 24, 2020.
Claims priority of provisional application 62/821,143, filed on Mar. 20, 2019.
Prior Publication US 2022/0190649 A1, Jun. 16, 2022
Int. Cl. H02J 50/30 (2016.01); H01L 31/054 (2014.01); H02S 40/30 (2014.01); H01L 31/0216 (2014.01)
CPC H02J 50/30 (2016.02) [H01L 31/02168 (2013.01); H01L 31/0547 (2014.12); H02S 40/30 (2014.12); Y02E 10/52 (2013.01)] 3 Claims
OG exemplary drawing
 
1. A power converting device for converting optical power into electrical power adapted for optical wireless power transmission using a laser beam, said power converting device comprising:
a photovoltaic cell having a plurality of conductors on a surface adapted to receive said laser beam, said photovoltaic cell having at least one junction having a bandgap energy between 0.75 eV and 1.2 eV; and
a cover layer disposed upon said photovoltaic cell, said cover layer comprising a material adapted to restrict transmission, by either absorption or reflection, of illumination having wavelengths outside of the range of the wavelength of said laser beam, and to transmit said laser beam towards said photovoltaic cell;
wherein:
said laser beam has a first wavelength between 700 nm and 1500 nm;
said wavelengths of said illumination outside of the range of said wavelength of said laser beam fall within a second range of wavelengths of 550 nm to 700 nm;
the transmission of said cover layer for said wavelength of said laser beam is at least 50% higher than its transmission for wavelengths within the second range of 550 nm to 700 nm, such that said power converting device has an efficiency of conversion to electrical power at said wavelength of said laser beam at least 2.5 times higher than its efficiency at a wavelength of 550 nm;
said cover layer being configured to absorb or reflect at least a third wavelength between 300 nm and 550 nm, so that at least 50% of the power of said third wavelength is absorbed or reflected before reaching said at least one junction, when illuminated through said cover layer from any direction between ±20° to the normal to the surface of said external layer, and said power converting device conversion efficiency for said third wavelength being less than 10%; and
said power converting device conversion efficiency for a fourth wavelength between 1500 nm and 2000 nm being below 5%.