Telewriting system

Claim 2

A telewriting system for transmitting information such as handwriting and graphics from an originating station to remote stations and reproducing said information at said remote stations comprising, in combination: a graphical input terminal including a stylus, a first writing surface upon which said stylus produces said information, and means for producing digital signals representative of the location of said stylus with respect to said surface; a transmitter for transmitting said digital signals along a transmission line so that said signals are substantially immune from signal distortions and noise introduced by said line, said transmitter including a first signal generator for generating synchronization signals to control the division of said digital signals into data words representative of said location of said stylus at any specified time, and timing means for controlling the insertion of said synchronization signals between said digital signals; a receiver at said remote stations for taking said digital signals from said transmission line and reconverting said digital signals into analog signals; a laser for writing upon a second writing surface; means responsive to said analog signals for deflecting said laser about said second writing surface so as to reproduce said information thereon at said remote stations; and a projector for projecting said second writing surface onto a viewing surface simultaneous with the reproduction of said information thereon.

Claim 3

Apparatus in accordance with claim 1 including a second signal generator for generating control signals for controlling the operation of auxiliary equipment at said remote locations, said timing means controlling the insertion of said control signals between said digital signals.

Claim 4

Apparatus in accordance with claim 2 wherein said transmitter and said receiver, respectively, include first and second data sets for inserting said digital, said synchronization, and said control signals on said transmission line in a preselected frequency band and at a preselected level at said originating station and for removing said signals from said line at said remote stations, respectively.

Claim 5

Apparatus in accordance with claim 1 wherein said transmitter includes register means for storing said digital signals from said graphical input terminal: a data set for linking said register means to said transmission line, said data set including a source of timing pulses; and means for using said timing pulses to control the movement of said digital signals from said input terminal to said register means and from said register means to said data set.

Claim 6

Apparatus in accordance with claim 1 wherein said receiver includes register means for storing said digital signals from said transmission line: a data set for linking said register means to said transmission line; detection means for detecting said synchronization and said control signals; digital to analog converter means for converting said digital signals to analog signals indicative of said location of said stylus; and means responsive to said detection means for controlling the movement of said digital signals from said register means to said digital to analog converter means.

Claim 7

Apparatus in accordance with claim 1 wherein said second writing surface is responsive to radiation in a specified frequency band, said laser generating radiation witHin said band, and said projector includes a source of radiation outside said frequency band whereby said second surface can be projected without affecting said information thereon.

Claim 8

A telewriting system for transmitting information such as handwriting and graphics from an originating station to remote stations and reproducing said information at said remote stations comprising, in combination: a graphical input terminal including a stylus, a first writing surface upon which said stylus produces said information, and means for producing digital signals representative of the location of said stylus with respect to said surface; a transmitter for transmitting said digital signals along a transmission line so that said signals are substantially immune from signal distortions and noise introduced by said line, said transmitter including means for inserting synchronization signals and control signals at preselected locations between said digital signals, said synchronization signals designating the locations at which said digital signals are divided into data words representing said location of said stylus at a specified time, said control signals controlling the operation of auxiliary equipment at said remote locations; a receiver at said remote stations for taking said digital signals from said transmission line and reconverting said digital signals into analog signals, said receiver including a detector for detecting said synchronization and said control signals; a laser for writing upon a second writing surface; means responsive to said analog signals for deflecting said laser about said second writing surface so as to reproduce said information thereon at said remote stations; and a projector for projecting said second writing surface onto a viewing surface simultaneous with the reproduction of said information thereon.

Claim 9

A telewriting system for transmitting information such as handwriting and graphics from an originating station to remote stations and reproducing said information at said remote stations comprising, in combination: a graphical input terminal including a stylus, a first writing surface upon which said stylus produces said information, and means for producing digital signals representative of the location of said stylus with respect to said surface; a transmitter for transmitting said digital signals along a transmission line so that said signals are substantially immune from signal distortions and noise introduced by said line, said transmitter including means for inserting synchronization signals and control signals at preselected locations between said digital signals, said synchronization signals designating the locations at which said digital signals are divided into data words representing said location of said stylus at a specified time, said control signals controlling the operation of auxiliary equipment at said remote locations; a receiver at said remote stations for taking said digital signals from said transmission line and reconverting said digital signals into analog signals, said receiver including a detector for detecting said synchronization and said control signals; a laser for writing upon a second writing surface; means responsive to said analog signals for deflecting said laser about said second writing surface so as to reproduce said information thereon at said remote stations; and a projector for projecting said second writing surface onto a viewing surface simultaneous with the reproduction of said information thereon.

Claim 10

Apparatus in accordance with claim 7 wherein said receiver includes a register for dividing said digital signals into data words and a converter for converting said digital data words to analog signals, said detector controlling the grouping of said digital signals into data words by said register in response to said synchronization signals.

Claim 11

A telewriting system for transmitting information such as writing and graphics from a first location and reproducing said information at a second location comprising, in combination: an input terminal at said first location including a first recording means on which said information is produced, and means for producing digital signals representative of said information; a transmitter for transmitting said digital signals along a transmission line including means for inserting synchronization and control signals at preselected locations between said digital signals, said synchronization signals designating the locations at which said digital signals are divided into data words representing segments of said information, said control signals controlling apparatus at said second location, and a data set for inserting said digital, synchronization and control signals on said transmission line; a receiver at said second location for receiving said signals from said transmission line including a detector for detecting said synchronization and control signals, and means responsive to said detector for converting said digital signals into analog signals representative of said information; a beam of radiation; a second recording means responsive to said beam; means responsive to said analog signals for deflecting said beam about said second recording means so as to reproduce said information thereon; and means for projecting said second recording means onto a viewing surface thereby to display said information.

Claim 12

A telewriting system for transmitting information such as writing and graphics from a first location and reproducing said information at a second location comprising, in combination: an input terminal at said first location including a first recording means on which said information is produced, and means for producing digital signals representative of said information; a transmitter for transmitting said digital signals along a transmission line including means for inserting synchronization and control signals at preselected locations between said digital signals, said synchronization signals designating the locations at which said digital signals are divided into data words representing segments of said information, said control signals controlling apparatus at said second location, and a data set for inserting said digital, synchronization and control signals on said transmission line; a receiver at said second location for receiving said signals from said transmission line including a detector for detecting said synchronization and control signals, and means responsive to said detector for converting said digital signals into analog signals representative of said information; a beam of radiation; a second recording means responsive to said beam; means responsive to said analog signals for deflecting said beam about said second recording means so as to reproduce said information thereon; and means for projecting said second recording means onto a viewing surface thereby to display said information.