THREE-PARTY SPEECH VIDEO TELEPHONE CONFERENCE SYSTEM

摘要

PURPOSE:To attain a conference among three parties with one video telephone set by connecting a line of each video telephone set to a 3-party speech circuit at an exchange side. CONSTITUTION:While subscribers A, B are in communication, if a subscriber C joins the speech, the subscriber A depresses a 3-party speech button 9 and sends the signal to an ISDN exchange 11. The ISDN exchange 11 uses the signal to operate a 3-party speech circuit 12 thereby connecting the lines of the three parties. Then the subscriber A dials a telephone number of the subscriber C by using a pushbutton 6. After the subscriber C is replied, the 3-party speech picture button 8 is depressed, then a picture 5 is split into a subscriber B picture 5a and a subscriber C picture 5b and the subscribers B, C are respectively displayed on them.