US3584143A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Facsimile duplication of documents by means of digital signals
Assignee: Polaroid Corp
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Filing: 1969-01-22
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Granted: 1971-06-08
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Expires: 1989-01-22
Abstract
Abstract This specification discloses a facsimile system for duplicating documents at a remote location by means of digital signals transmitted over a conventional telephone line. The system scans the original document to determine the position of transitions in the original documents and digitally encode these positions. The resulting digital signals are transmitted to a remote location where a receiver in response to the received signals produces a facsimile of the original document. In the scanning of the original document, horizontal lines of the document are repeatedly scanned at a high rate and on each horizontal scan of a line, the position of only one or two transitions is encoded. The scanning of each horizontal line is repeated until all the transitions have been encoded. The resulting encoded positions are transmitted to a remote receiver as they are encoded. During each scan, usually, the position of a white-to-black transition in the scanned line is encoded and the relative position of the following black-to-white transition in the scanned line is encoded. The positions of a pair of such transitions are encoded during a single scan if the black-to-white transition of such pair closely follows the white-to-black transition of such pair. If the black-to-white transition does not closely follow the white-to-black transition, then the position of the black-towhite transition is encoded on the next following scan of the line.
Inventors
- 👤 Nathan Gold
- 👤 Richard F Weeks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 06:39
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/41; H04N1/411; H04N1/413
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
107 words
A facsimile transmitter for generating signals from which a document can be duplicated comprising means to scan the document to be duplicated, detecting means to detect transitions in said document as it is scanned by said scanning means, control means responsive to said detecting means to control said scanning means to scan the portions of said document containing transitions repeatedly and to scan portions of said documents containing no transitions a smaller number of times then said portions containing transitions are scanned, said control means including means to generate signals to a remote receiver, representing the positions of said transitions, synchronously with said scan of said document.
Claim 2
Dependent Claim
107 words
A facsimile transmitter for generating signals from which a document can be duplicated comprising means to scan the document to be duplicated, detecting means to detect transitions in said document as it is scanned by said scanning means, control means responsive to said detecting means to control said scanning means to scan the portions of said document containing transitions repeatedly and to scan portions of said documents containing no transitions a smaller number of times then said portions containing transitions are scanned, said control means including means to generate signals to a remote receiver, representing the positions of said transitions, synchronously with said scan of said document.
Claim 3
Dependent Claim
20 words
The invention as described in claim 1, wherein said synChronously generated signals comprise a fixed predetermined number of binary bits.
Claim 4
Dependent Claim
27 words
A facsimile transmitter as recited in claim 1, wherein said control means controls said scanning means to scan portions of said document containing no transitions only once.
Claim 5
Dependent Claim
57 words
A facsimile transmitter as recited in claim 1, wherein said control means controls said scanning means to scan successive parallel lines in said document and includes means responsive to said detecting means failing to detect a transition in a line to step said scanning means to scan the next successive line on said document to be duplicated.
Claim 6
Dependent Claim
104 words
A facsimile transmitter for generating signals from which a document can be duplicated to a remote receiver, comprising means to scan the document to be duplicated, detecting means to detect transitions in said document as it is scanned by said scanning means, control means to cause said scanning means to scan different lines of said document in succession and to scan the lines of said document containing transitions repeatedly, said control means including means to generate signals to said remote receiver synchronously with said scan and representing the positions of a small number of different transitions during each successive scan of the same line.
Claim 7
Dependent Claim
104 words
A facsimile transmitter for generating signals from which a document can be duplicated to a remote receiver, comprising means to scan the document to be duplicated, detecting means to detect transitions in said document as it is scanned by said scanning means, control means to cause said scanning means to scan different lines of said document in succession and to scan the lines of said document containing transitions repeatedly, said control means including means to generate signals to said remote receiver synchronously with said scan and representing the positions of a small number of different transitions during each successive scan of the same line.
Claim 8
Dependent Claim
33 words
A facsimile receiver for receiving signals generated by a facsimile transmitter as recited in claim 5 and including means to produce a facsimile of said document to be transmitted from said received signals.
Claim 9
Dependent Claim
48 words
A facsimile system comprising a transmitter as recited in claim 5, and a facsimile receiver in a location remote from said transmitter adapted to receive signals generated by said transmitter, said receiver including means to produce facsimile of said original document from the signals received from said transmitter.
Claim 10
Dependent Claim
30 words
A facsimile transmitter as recited in claim 5, wherein the number of transition positions which are represented by signals generated on each scan of a line is less than three.
Claim 11
Dependent Claim
23 words
A facsimile transmitter as recited in claim 5, wherein said means to generate signals generates digital signals representing the positions of said transitions.
Claim 12
Dependent Claim
48 words
A facsimile transmitter as recited in claim 5, wherein said control means includes means to generate signals representing the positions of transitions of a first type and signals representing the positions of transitions of a second type relative to the positions of said transitions of said first type.
Claim 13
Dependent Claim
28 words
A facsimile transmitter as recited in claim 10, wherein said transitions of said first type in light-to-dark transitions and said transitions of said second type are dark-to-light transitions.
Claim 14
Dependent Claim
75 words
A facsimile transmitter as recited in claim 10, wherein said means to generate signals generates binary signals of a first number of bits to represent each position of the transitions of said first type and generates binary signals of a second number of bits less than said first number of bits to represent each of the positions of the transitions of said second type relative to the positions of said transitions of said first type.
Claim 15
Dependent Claim
129 words
A facsimile transmitter as recited in claim 10, wherein said generating means is operable to generate signals representing the position of a transition of said first type and the position of the next succeeding transition of said second type relative to the position of the preceding transition of said first type on the same scan of the line only if such next succeeding transition of said second type is within a predetermined distance of such preceding transition of said first type, said generating means generating signals representing the position of such next succeeding transition of said second type on the next succeeding scan of the same line if the distance of such next succeeding transition from such preceding transition of said first type is greater than said predetermined distance.
Claim 16
Independent Claim
74 words
A method of duplicating a document at a remote location comprising scanning the portions of said document containiNg transitions repeatedly, scanning portions of said document containing no transitions a fewer number of times than said portions containing transitions are scanned, generating signals representing the positions of said transitions as said transitions are scanned, transmitting said signals to a remote location synchronously with said scanning, and producing a facsimile of said document from said signals.
Claim 17
Independent Claim
74 words
A method of duplicating a document at a remote location comprising scanning the portions of said document containiNg transitions repeatedly, scanning portions of said document containing no transitions a fewer number of times than said portions containing transitions are scanned, generating signals representing the positions of said transitions as said transitions are scanned, transmitting said signals to a remote location synchronously with said scanning, and producing a facsimile of said document from said signals.
Claim 18
Dependent Claim
89 words
A method of duplicating a document at a remote location as recited in claim 14 wherein the step of generating signals representing the positions of said transitions comprises generating signals to represent the positions of transitions of a first type relative to a reference line, generating signals to represent the positions of each transition of a second type relative to the positions of preceding transitions of said first type if such transitions of said second type are within a predetermined distance of the preceding transitions of said first type.
Claim 19
Dependent Claim
82 words
A facsimile transmitter for generating signals from which a document can be duplicated, comprising: means to scan the document line by line; means to detect transitions in said document during the scanning thereof; and means connected to said detecting means for generating digital signals representing the positions of transitions of first and second types during each line scan; said signals comprising a fixed word length for transitions of said first type and a variable word length for transitions of said second type.
Claim 20
Dependent Claim
82 words
A facsimile transmitter for generating signals from which a document can be duplicated, comprising: means to scan the document line by line; means to detect transitions in said document during the scanning thereof; and means connected to said detecting means for generating digital signals representing the positions of transitions of first and second types during each line scan; said signals comprising a fixed word length for transitions of said first type and a variable word length for transitions of said second type.
Claim 21
Dependent Claim
55 words
The invention as delineated in claim 16, wherein said fixed word length signal contains a predetermined number of binary bits and said variable word length signal contains a predetermined number of binary bits which varies as a function of the location of transitions of said second type with respect to ones of said first type.
Claim 22
Dependent Claim
38 words
The invention as stated in claim 17, wherein the number of bits comprising said variable word length varies from a predetermined amount only when the distance between transitions of said first and second types exceeds a predetermined amount.
Claim 23
Dependent Claim
33 words
The invention as set forth in claim 18, further including means for transmitting said transition position information to a remote receiver synchronously with each line scan via a fixed number of binary bits.
Claim 24
Dependent Claim
108 words
A facsimile transmitter for generating signals from which a document may be duplicated to a remote receiver, including: means to scan said document line by line; means to detect transitions of different types in said document; first means for generating binary coded digital signals responsive to a first type of detected transition; second means for generating binary coded digital signals responsive to a second type of detected transition; and means for causing said first means to generate binary coded digital signals responsive to said second type of detected transition when said second type of detected transition occurs beyond a predetermined distance from said first type of detected transition.
Claim 25
Dependent Claim
108 words
A facsimile transmitter for generating signals from which a document may be duplicated to a remote receiver, including: means to scan said document line by line; means to detect transitions of different types in said document; first means for generating binary coded digital signals responsive to a first type of detected transition; second means for generating binary coded digital signals responsive to a second type of detected transition; and means for causing said first means to generate binary coded digital signals responsive to said second type of detected transition when said second type of detected transition occurs beyond a predetermined distance from said first type of detected transition.
Claim 26
Dependent Claim
143 words
A receiver for reproducing a facsimile of a document transmitted from a remote transmitter, including: first means for receiving and storing binary coded digital signals corresponding to transitions occurring in said document; second means for receiving and storing binary coded signals corresponding to transitions occurring in said document; means for reproducing a facsimile of transitions of a first type in response to said digital signals received and stored in said first means; means for reproducing a facsimile of transitions of a second type in response to said digital signals received and stored in said second means; and means for causing said facsimile transition reproducing means to reproduce facsimiles of transitions of said second type in response to signals received and stored in said first means when transitions of said second type are positioned beyond a predetermined distance from transitions of said first type.
Claim 27
Dependent Claim
143 words
A receiver for reproducing a facsimile of a document transmitted from a remote transmitter, including: first means for receiving and storing binary coded digital signals corresponding to transitions occurring in said document; second means for receiving and storing binary coded signals corresponding to transitions occurring in said document; means for reproducing a facsimile of transitions of a first type in response to said digital signals received and stored in said first means; means for reproducing a facsimile of transitions of a second type in response to said digital signals received and stored in said second means; and means for causing said facsimile transition reproducing means to reproduce facsimiles of transitions of said second type in response to signals received and stored in said first means when transitions of said second type are positioned beyond a predetermined distance from transitions of said first type.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-07 | 1974-12-07 | 1975-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-07 | 1978-12-07 | 1979-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-07 | 1982-12-07 | 1983-06-08 | $7700.00 | Window Closed / Lapsed |