The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 2009
Filed:
Oct. 29, 2004
Kouichi Ichimura, Yokohama, JP;
Noritsugu Shiokawa, Yokohama, JP;
Mikio Fujii, Kawasaki, JP;
Kentaro Torii, Tokyo, JP;
Kenji Ohkuma, Yokohama, JP;
Kouichi Ichimura, Yokohama, JP;
Noritsugu Shiokawa, Yokohama, JP;
Mikio Fujii, Kawasaki, JP;
Kentaro Torii, Tokyo, JP;
Kenji Ohkuma, Yokohama, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
In the method of the present invention, one of each pair of photons connected through entanglement is distributed to a transmitting station, relay stations and a receiving station. After the photons reach secure sites, such as the relay stations, a base for detecting photons is determined between adjacent sites, and then photons are detected in each site, which makes it possible to obtain a secret key used for secure information transmission between relay stations using bases coincide with each other every time. Also, in the present invention, a high-quality random number sequence serving as a secret key is automatically generated in a physical manner every time by detecting a superposition state of an entanglement and procedures corresponding to those in which a secret key itself is transmitted in a form of a quantum cryptogram are performed.