US3867571A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flying spot scanner
Assignee: Xerox Corp
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Filing: 1972-11-27
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Granted: 1975-02-18
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Expires: 1992-11-27
Abstract
Abstract A flying spot scanning system is provided by utilizing reflected light from a multifaceted rotating polygon which is then directed to the scanned medium. A light source illuminates at least one of the facets of the polygon during each scanning cycle to provide the spot scan. In each scanning cycle, information is transmitted to scanned medium by modulating the light from the light source in accordance with a video signal. To assure a uniform spot size at the scanned medium, an optical convolution of elements is selected in combination with the light source such that an adequate depth of focus at the medium is assured. An imaging lens is provided in series with a lens, which expands an original light beam, to converge the expanded beam to illuminate the selected facet or contiguous facets that are to control the movement of a spot throughout a scan angle. In the preferred embodiment, the rotation of the polygon is synchronized in phased relation to the scan rate used to obtain the video signal.
Inventors
- 👤 Gary K Starkweather
- 👤 David E Damouth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:28
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/04; H04N1/047; H04N1/053; B; B41; B41J; B41J2/00; B41J2/435; B41J2/47; B41J2/471; G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1204; G06K15/1219; H04N3/00; H04N3/02; H04N3/08; H04N1/113; H04N1/1135; H04N1/12; H04N2201/00; H04N2201/024; H04N2201/02406; H04N2201/02439; H04N2201/02443; H04N2201/04; H04N2201/047; H04N2201/04701; H04N2201/0471; H04N2201/04744; H04N2201/04753; H04N2201/04758; H04N2201/04767; H04N2201/04768; H04N2201/04794; H04N2201/04798
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
155 words
An electro-optical system for recording information from an electrical signal onto a scanned medium comprising: means for providing a beam of high intensity light, means for modulating the light beam in accordance with the information content of an electrical signal comprising a bit stream, first optical means for expanding said modulated beam, second optical means in convolution with said first optical means for imaging said expanded beam to a spot in a focal plane at a predetermined distance from said second optical means, scanning means positioned between said second means and the focal plane for scanning the spot across a light sensitive medium in said focal plane to impart the information content of said spot to said medium, and electrical means for synchronizing the transmission rate of the electrical signal to the velocity of the spot across the medium, said electrical means varying the number of bits per second in accordance with a predetermined function.
Claim 2
Dependent Claim
155 words
An electro-optical system for recording information from an electrical signal onto a scanned medium comprising: means for providing a beam of high intensity light, means for modulating the light beam in accordance with the information content of an electrical signal comprising a bit stream, first optical means for expanding said modulated beam, second optical means in convolution with said first optical means for imaging said expanded beam to a spot in a focal plane at a predetermined distance from said second optical means, scanning means positioned between said second means and the focal plane for scanning the spot across a light sensitive medium in said focal plane to impart the information content of said spot to said medium, and electrical means for synchronizing the transmission rate of the electrical signal to the velocity of the spot across the medium, said electrical means varying the number of bits per second in accordance with a predetermined function.
Claim 3
Dependent Claim
50 words
The system as defined in claim 1 wherein the scanning means includes a multifaceted polygon having reflective sides for reflecting the light converging from said second optical means onto said medium and means for rotating said polygon such that the reflected light is scanned in successive traces across said medium.
Claim 4
Dependent Claim
25 words
The system as defined in claim 2 wherein said light source is a laser which emits a beam of collimated light of substantially uniform intensity.
Claim 5
Dependent Claim
52 words
The system as defined in claim 3 wherein said electrical means includes a function generator with an output waveform proportionate to the variation in velocity of the spot as it scans said medium, whereby the transmission rate of the electrical signal is proportionate to the velocity of the spot in each scan.
Claim 6
Dependent Claim
30 words
The system as defined in claim 4 wherein the output waveform is the function 1/secant2 Alpha , where Alpha is the angle of scan of said beam from said polygon.
Claim 7
Dependent Claim
134 words
A flying spot scanning system for recording information from an electrical signal onto a scanned medium comprising: means for providing a beam of high intensity light, means for modulating the light beam in accordance with the information content of an electrical signal represented by a stream of binary digits, means for focusing said modulated beam to a spot upon the surface of a light sensitive medium, scanning means positioned in the optical path of said modulated beam for scanning the spot across said medium to impart the information content of said spot to said medium, and electrical means for synchronizing the bit rate of the stream of binary digits to the velocity of the spot across the medium, said electrical means varying the number of bits per second in accordance with a predetermined function.
Claim 8
Dependent Claim
134 words
A flying spot scanning system for recording information from an electrical signal onto a scanned medium comprising: means for providing a beam of high intensity light, means for modulating the light beam in accordance with the information content of an electrical signal represented by a stream of binary digits, means for focusing said modulated beam to a spot upon the surface of a light sensitive medium, scanning means positioned in the optical path of said modulated beam for scanning the spot across said medium to impart the information content of said spot to said medium, and electrical means for synchronizing the bit rate of the stream of binary digits to the velocity of the spot across the medium, said electrical means varying the number of bits per second in accordance with a predetermined function.
Claim 9
Dependent Claim
47 words
The system as defined in claim 6 wherein the scanning means includes a multifaceted polygon having reflective sides for reflecting the light incident to it onto said medium and means for rotating said polygon such that the reflected light is scanned in successive traces across said medium.
Claim 10
Dependent Claim
25 words
The system as defined in claim 7 wherein said light source is a laser which emits a beam of collimated light of substantially uniform intensity.
Claim 11
Dependent Claim
40 words
The system as defined in claim 8 wherein the bit rate of the signal is determined by means for clocking the bit stream, said clocking means having an output frequency dependent upon an input voltage for varying said bit rate.
Claim 12
Dependent Claim
60 words
The system as defined in claim 8 wherein said electrical means includes a function generator with an output waveform proportionate to the variation in velocity of the spot as it scans said medium, said output waveform being the input voltage to said clocking means, whereby said bit rate is varied proportionate to the velocity of the spot in each scan.
Claim 13
Dependent Claim
30 words
The system as defined in claim 10 wherein the output waveform is the function 1/secant2 Alpha , where Alpha is the angle of scan of said beam from said polygon.
Claim 14
Independent Claim
110 words
A method for recording information from an electrical signal onto a scanned medium comprising the steps of: providing a beam of high intensity light, modulating the light beam in accordance with the information content of an electrical signal represented by a stream of binary digits, focusing said modulated beam to a spot upon the surface of a light sensitive medium, scanning said spot across said medium to impart the information content of said spot to said medium, synchronizing the bit rate of the stream of binary digits to the velocity of the spot across the medium, and varying the number of bits per second in accordance with a predetermined function.
Claim 15
Independent Claim
110 words
A method for recording information from an electrical signal onto a scanned medium comprising the steps of: providing a beam of high intensity light, modulating the light beam in accordance with the information content of an electrical signal represented by a stream of binary digits, focusing said modulated beam to a spot upon the surface of a light sensitive medium, scanning said spot across said medium to impart the information content of said spot to said medium, synchronizing the bit rate of the stream of binary digits to the velocity of the spot across the medium, and varying the number of bits per second in accordance with a predetermined function.
Claim 16
Dependent Claim
47 words
The method as defined in claim 12 wherein said synchronizing step includes synchronizing the bit rate from a predetermined rate in accordance with said predetermined function such that said bit rate is proportional to the velocity of said spot at any given point in a given scan.
Claim 17
Dependent Claim
32 words
The method as defined in claim 13 wherein the predetermined bit rate in said synchronizing step is varied in accordance with the function 1/secant2 Alpha , where Alpha is the scan angle.
References Cited (Backward Citations)
US3573849A
Cited
US3701999A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |