Inventor · disambiguated record
Tatsuaki Okamoto
Also filed as: OKAMOTO TATSUAKI
30 granted patents·2,153 citations·filing 1985–2021
97Inventor score
Files withNIPPON TELEGRAPH & TELEPHONE15TAKASHIMA KATSUYUKI10MITSUBISHI ELECTRIC CORP4SUZUKI KOUTAROU1
Top patents by PatentIndex Score
30 records- 0197US4977595AMethod and apparatus for implementing electronic cashNIPPON TELEGRAPH & TELEPHONE·Filed 1990·Granted Dec 11, 1990·433 cites·54 claims
- 0290US4625076ASigned document transmission systemNIPPON TELEGRAPH & TELEPHONE·Filed 1985·Granted Nov 25, 1986·149 cites·25 claims
- 0387US8938623B2Cryptographic processing system, key generation device, encryption device, decryption device, cryptographic processing method, and cryptographic processing programTAKASHIMA KATSUYUKI·Filed 2011·Granted Jan 20, 2015·12 cites·8 claims
- 0486US8913742B2Cryptographic processing system, key generation device, encryption device, decryption device, signature processing system, signature device, and verification deviceTAKASHIMA KATSUYUKI·Filed 2011·Granted Dec 16, 2014·11 cites·15 claims
- 0582US8559638B2Cryptographic processing systemTAKASHIMA KATSUYUKI·Filed 2010·Granted Oct 15, 2013·6 cites·47 claims
- 0679US6072876AMethod and system for depositing private key used in RSA cryptosystemNIPPON TELEGRAPH & TELEPHONE·Filed 1997·Granted Jun 6, 2000·127 cites·30 claims
- 0777US5396558AMethod and apparatus for settlement of accounts by IC cardsNIPPON TELEGRAPH & TELEPHONE·Filed 1993·Granted Mar 7, 1995·235 cites·12 claims
- 0876US9413531B2Cryptographic system, cryptographic method, cryptographic program, and decryption deviceMITSUBISHI ELECTRIC CORP·Filed 2013·Granted Aug 9, 2016·4 cites·12 claims
- 0973US5926548AMethod and apparatus for implementing hierarchical electronic cashNIPPON TELEGRAPH & TELEPHONE·Filed 1997·Granted Jul 20, 1999·215 cites·13 claims
- 1070US9183411B2Cryptographic processing system, key generation device, encryption device, decryption device, cryptographic processing method, and cryptographic processing program utilizing attribute information for generation of a key for decryption or encryptionTAKASHIMA KATSUYUKI·Filed 2011·Granted Nov 10, 2015·3 cites·8 claims
- 1170US8577030B2Cryptographic processing system, key generation device, key delegation device, encryption device, decryption device, cryptographic processing method, and cryptographic processing programTAKASHIMA KATSUYUKI·Filed 2010·Granted Nov 5, 2013·3 cites·5 claims
- 1270US5224162AElectronic cash systemNIPPON TELEGRAPH & TELEPHONE·Filed 1992·Granted Jun 29, 1993·194 cites·11 claims
- 1368US5901229AElectronic cash implementing method using a trusteeNIPPON TELEGRAPH & TELEPHONE·Filed 1996·Granted May 4, 1999·163 cites·24 claims
- 1467US7222108B2Electronic cash implementing method and equipment using user signature and recording medium recorded thereon a program for the methodNIPPON TELEGRAPH & TELEPHONE·Filed 2002·Granted May 22, 2007·13 cites·12 claims
- 1567US4969189AAuthentication system and apparatus thereforNIPPON TELEGRAPH & TELEPHONE·Filed 1989·Granted Nov 6, 1990·127 cites·31 claims
- 1666US6480605B1Encryption and decryption devices for public-key cryptosystems and recording medium with their processing programs recorded thereonNIPPON TELEGRAPH & TELEPHONE·Filed 1998·Granted Nov 12, 2002·72 cites·31 claims
- 1766US6212637B1Method and apparatus for en-bloc verification of plural digital signatures and recording medium with the method recorded thereonNIPPON TELEGRAPH & TELEPHONE·Filed 1998·Granted Apr 3, 2001·59 cites·70 claims
- 1865US9106408B2Signature processing system, key generation device, signature device, verification device, signature processing method, and signature processing programTAKASHIMA KATSUYUKI·Filed 2011·Granted Aug 11, 2015·2 cites·10 claims
- 1964US5502765AMethod and apparatus for settlement of accounts by IC cardsNIPPON TELEGRAPH & TELEPHONE·Filed 1994·Granted Mar 26, 1996·129 cites·6 claims
- 2061US6003765AElectronic cash implementing method with a surveillance institution, and user apparatus and surveillance institution apparatus for implementing the sameNIPPON TELEGRAPH & TELEPHONE·Filed 1997·Granted Dec 21, 1999·64 cites·21 claims
- 2160US9385867B2Cryptographic processing system, key generation device, encryption device, decryption device, key delegation device, cryptographic processing method, and cryptographic processing programTAKASHIMA KATSUYUKI·Filed 2011·Granted Jul 5, 2016·1 cites·12 claims
- 2253US11888968B2Signature device, verification device, signature method, verification method, and computer readable mediumMITSUBISHI ELECTRIC CORP·Filed 2021·Granted Jan 30, 2024·0 cites·13 claims
- 2351US11909873B2Decryption device, cryptographic system, and decryption methodMITSUBISHI ELECTRIC CORP·Filed 2021·Granted Feb 20, 2024·0 cites·8 claims
- 2450US6539364B2Electronic cash implementing method and equipment using user signature and recording medium recorded thereon a program for the methodNIPPON TELEGRAPH & TELEPHONE·Filed 1998·Granted Mar 25, 2003·69 cites·25 claims
- 2550US5446796AMethod and apparatus for settlement of accounts by IC cardsNIPPON TELEGRAPH & TELEPHONE·Filed 1994·Granted Aug 29, 1995·62 cites·4 claims
- 2647US9203622B2Cryptographic processing system, cryptographic processing method, cryptograhpic processing program, and key generation deviceTAKASHIMA KATSUYUKI·Filed 2012·Granted Dec 1, 2015·0 cites·15 claims
- 2744US9722783B2Cryptographic systemMITSUBISHI ELECTRIC CORP·Filed 2013·Granted Aug 1, 2017·0 cites·12 claims
- 2844US9407438B2Cryptographic system, cryptographic method, and cryptographic programTAKASHIMA KATSUYUKI·Filed 2013·Granted Aug 2, 2016·0 cites·11 claims
- 2942US8458478B2Signature generating apparatus, signature verifying apparatus, and methods and programs thereforSUZUKI KOUTAROU·Filed 2008·Granted Jun 4, 2013·0 cites·28 claims
- 3039US8929542B2Cryptographic processing system, key generation device, key delegation device, encryption device, decryption device, cryptographic processing method, and cryptographic processing programTAKASHIMA KATSUYUKI·Filed 2010·Granted Jan 6, 2015·0 cites·6 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →