1. Field of the Invention
The present invention relates to a communication terminal apparatus to be used for a remote meeting (a meeting held between persons who are physically apart from each other, a certain communication system thus being needed to enable these persons to communicate with each other), which apparatus has such functions as communicating through so-called tele-writing and controlling documents.
2. Discussion of the Background
A tele-writing apparatus is defined in the CCITT (International Telegraph and Telephone Consultative Committee) Recommendation T.150, as being a remote communication terminal which communicates with another remote communication terminal via a communication line, which terminal has a display device and a hand writing inputting device, which terminal transfers hand writing input information, that is, information which has been input by hand writing, to the other terminal while a conversation is taking place, and which terminal helps the persons taking part in the conversation to understand the transferred hand writing input information by displaying it.
The Shimazu corporation has developed such a tele-writing apparatus named "pen-telephone" (type TW101, hand writing communication terminal equipment with a facsimile function), which apparatus displays, on respective liquid crystal displays of both the present apparatus and another apparatus, drawing information comprising characters and diagrams, the liquid crystal displays having transparent tablets respectively formed therein, and inputs information by hand writing on the transparent tablets so that the corresponding input image information is displayed on the liquid crystal displays of both the apparatuses in real time.
Further, in a system for a remote meeting utilizing such tele-writing apparatuses, it is necessary to communicate, that is, transmit and receive, and treat the following two types of data: a bulk type data and a real time type data. The bulk type data is typically utilized as a facsimile data based on raster images, and the real time type data is typically utilized as a tele-writing data based on position information.
Either only the tele-writing apparatus itself may be used, or the tele-writing apparatus may be used together with a display of a raster image, in a remote meeting. In the remote meeting, a common document is displayed on both apparatuses, the contents of the displayed document being then controlled (modified) through the real time type data. The document controlling (modifying) may include specifying the document, modifying it by hand writing, enlarging/reducing the size thereof, scrolling the contents, and rotating a direction thereof.
In the "pen-telephone", it is possible for the hand writing inputting to be performed only with respect to the presently displayed contents. Thus, in a case where a memorandum to be referred to in the present conversation includes a plurality of pages, it is necessary that the presently displayed contents is to be deleted after the contents are printed out once, and further, it is then necessary that the other hand written information be written.
This action interrupts the smooth proceeding of a remote meeting, and further the previous drawing information, which has been deleted after printing of the displayed contents, cannot be displayed again. Further, the "pen-telephone" does not have functions for storing a memorandum including a plurality of pages.
Further, the tele-writing apparatus according to the CCITT Recommendation T.150 only transmits/receives hand written information. It does not define other functions for transmitting/receiving a document and other functions for displaying/controlling contents of the document. Such a tele-writing apparatus cannot provide a smooth remote meeting.
Further, according to the Recommendation T.150, it is normal for the tele-writing apparatus to be used alone. Thus, it is possible to use the apparatus for making a memorandum of a meeting. Further, in a case where the operation mode of the tele-writing apparatus is changed between a first simple tele-writing mode and a second mode in which a document is transmitted/received, it is necessary to store the presently displayed file of information, to finish the current operation according to the first mode, to start another operation according to the second mode, and then to load the file. Such troublesome operations may interfere with the smooth proceeding of the meeting.