A communication device having a facsimile module that can carry out confidential communication regardless of the type of communication device of a caller. A called station number (telephone or facsimile number) detector to which a telephone set on a called side is connected is an integrated...http://www.google.com.tw/patents/US5727050?utm_source=gb-gplus-share專利 US5727050 - Communication device having a facsimile module for carrying out confidential communication 
