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US4881086A Expired / Lapsed US ⏱️ 0.0 years remaining

Laser recorder with sheet edge detection

Assignee: Minolta Co Ltd
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Filing: 1988-08-26
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Granted: 1989-11-14
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Expires: 2008-08-26
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Abstract

Abstract A laser-beam image recording apparatus for recording images on a light-sensitive sheet medium through irradiation of an information-carrying laser beam, comprising a laser beam generator for emitting a laser beam, a polygonal mirror for directing the laser beam toward a linear zone and deflecting the laser beam to swing repeatedly along the linear zone, roller arrangement for transporting a light-sensitive sheet medium to pass through the linear zone, a sensor for detecting an arrival of the leading edge of the sheet medium at the linear zone, and a control circuit for modulating the laser beam to be generated by the laser beam generator, the control circuit being operative to modulate the laser beam depending on the image to be recorded on a leading portion of a light-sensitive sheet medium before the sensor detects that the leading edge of the sheet medium which has been advancing toward the linear zone reaches the linear zone and to modulate the laser beam depending on the images to be recorded on a portion subsequent to the leading portion of the sheet medium after the sensor detects that the leading edge of the sheet medium advanced toward the linear zone has reached the linear zone.

Inventors

  • 👤 Naoya Misawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 14:51
CPC Classifications
G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1204; G06K15/1219

Claims Analysis

Total Claims: 33
Claim 1
Independent Claim 282 words
A laser-beam image recording apparatus for recording images on a light-sensitive sheet medium through irradiation of an information-carrying laser beam modulated depending on the image to be recorded by the beam, comprising (a) laser beam generating means for emitting a laser beam, (b) deflecting means for directing said laser beam toward a linear zone and deflecting the laser beam to swing repeatedly along the linear zone, (c) means for transporting a light-sensitive sheet medium to pass through said linear zone, (d) detecting means for detecting an arrival of the leading edge of the sheet medium at said linear zone, said detecting means including a sensor for producing an output signal responsive to the laser beam incident on said linear zone, the detecting means being operative to detect the arrival of the leading edge of the sheet medium at said linear zone on the basis of said signal, (e) said laser beam generating means having a first state operative to generate a laser beam for enabling said detecting means to detect the leading edge of a light-sensitive sheet medium, and a second state operative to generate said information-carrying laser beam, and (f) control means for controlling said laser beam generating means, said control means being operative to maintain said laser beam generating means in said first state before said detecting means detects that the leading edge of a light-sensitive sheet medium which has been advancing toward said linear zone reaches the linear zone and to shift the laser beam generating means from said first state into said second state after said detecting means detects that the leading edge of the light-sensitive sheet medium advanced toward said linear zone has reached the linear zone.
Claim 2
Dependent Claim 282 words
A laser-beam image recording apparatus for recording images on a light-sensitive sheet medium through irradiation of an information-carrying laser beam modulated depending on the image to be recorded by the beam, comprising (a) laser beam generating means for emitting a laser beam, (b) deflecting means for directing said laser beam toward a linear zone and deflecting the laser beam to swing repeatedly along the linear zone, (c) means for transporting a light-sensitive sheet medium to pass through said linear zone, (d) detecting means for detecting an arrival of the leading edge of the sheet medium at said linear zone, said detecting means including a sensor for producing an output signal responsive to the laser beam incident on said linear zone, the detecting means being operative to detect the arrival of the leading edge of the sheet medium at said linear zone on the basis of said signal, (e) said laser beam generating means having a first state operative to generate a laser beam for enabling said detecting means to detect the leading edge of a light-sensitive sheet medium, and a second state operative to generate said information-carrying laser beam, and (f) control means for controlling said laser beam generating means, said control means being operative to maintain said laser beam generating means in said first state before said detecting means detects that the leading edge of a light-sensitive sheet medium which has been advancing toward said linear zone reaches the linear zone and to shift the laser beam generating means from said first state into said second state after said detecting means detects that the leading edge of the light-sensitive sheet medium advanced toward said linear zone has reached the linear zone.
Claim 3
Dependent Claim 65 words
A laser-beam image recording apparatus as set forth in claim 1, in which said deflecting means comprises a rotatable polygonal mirror located to receive a laser beam from said laser beam generating means and re-direct the incident laser beam toward said linear zone, the laser beam incident on the linear zone being deflected to swing repeatedly along the linear zone as said polygonal mirror rotates.
Claim 4
Dependent Claim 44 words
A laser-beam image recording apparatus as set forth in claim 1, in which said laser beam generating means comprises a semiconductor laser radiation element and in which said control means is operative to control an electric signal to activate said semiconductor laser radiation element.
Claim 5
Dependent Claim 77 words
A laser-beam image recording apparatus as set forth in claim 1, in which said sensor is located to receive a laser beam reflected from a light-sensitive sheet medium extending through said linear zone and in which said control means is operative to control said laser beam generating means so that the generated by the laser beam generating means is directed to said sensor only in the presence of a light-sensitive sheet medium extending through said linear zone.
Claim 6
Dependent Claim 79 words
A laser-beam image recording apparatus as set forth in claim 4, in which said deflecting means and said linear zone are arranged so that, in the presence of a light-sensitive sheet medium extending through said linear zone, a laser beam generated by said laser beam generating means is incident on the light-sensitive sheet at a predetermined angle less than 90 degrees with respect to a plane normal to the surface of the sheet medium extending through the linear zone.
Claim 7
Dependent Claim 114 words
A laser-beam image recording apparatus as set forth in claim 4, in which said transport means comprises a support member having a light-absorptive surface for receiving thereon a light-sensitive sheet medium extending through said linear zone so that, in the presence of a light-sensitive sheet medium extending through said linear zone, a laser beam directed toward said linear zone is reflected from the surface of the light-sensitive sheet medium and re-directed toward said sensor and, in the absence of a light-sensitive sheet medium extending through said linear zone, a laser beam directed toward said linear zone is absorbed in the light-absorptive surface of said support member and is substantially not re-directed toward said sensor.
Claim 8
Dependent Claim 58 words
A laser-beam image recording apparatus as set forth in claim 6, in which said support member consists of a cylindrical drum having a center axis and rotatable about the center axis for transporting a light-sensitive sheet medium received on the peripheral surface thereof, said light-absorptive surface of said support member comprising the peripheral surface of said cylindrical drum.
Claim 9
Dependent Claim 70 words
A laser-beam image recording apparatus as set forth in claim 1, in which said sensor is located, in a direction in which a laser beam is to be directed toward said linear zone, beyond a plane containing said linear zone so that a laser beam directed toward said linear zone is allowed to reach said sensor only in the absence of a light-sensitive sheet medium extending through said linear zone.
Claim 10
Dependent Claim 48 words
A laser-beam image recording apparatus as set forth in claim 1, in which said control means is operative to control said laser beam generating means so that the laser beam generating means continuously generates a laser beam when the laser beam generating means is in said first state.
Claim 11
Dependent Claim 84 words
A laser-beam image recording apparatus as set forth in claim 1, in which said sensor is located to receive a laser beam directed to a predetermined location with respect to the direction in which the laser beam is incident on said linear zone, the deflecting means being operative to direct a laser beam toward said predetermined location only at a timing at which the laser beam is to pass through the predetermined location when said laser beam generating means is in said first state.
Claim 12
Dependent Claim 70 words
A laser-beam image recording apparatus as set forth in claim 1, in which said control means is operative to control said laser beam generating means such that said laser beam generating means generates a laser beam modulated depending on the images to be recorded on a leading end portion of a light-sensitive sheet medium supplied to said linear zone when the laser beam generating means is in said first state.
Claim 13
Dependent Claim 89 words
A laser beam image recording apparatus as set forth in claim 11, in which said sensor is located to receive a laser beam directed to a predetermined location with respect to the direction in which the laser beam is incident on said linear zone, said control means being operative to control said laser beam generating means to generate a laser beam at least at a timing at which the laser beam is to pass through said predetermined location when said laser beam generating means is in said first state.
Claim 14
Dependent Claim 210 words
A laser-beam image recording apparatus for recording images on a light-sensitive sheet medium through irradiation of an information-carrying laser beam, comprising (a) laser beam generating means for emitting a laser beam, (b) deflecting means for directing said laser beam toward a linear zone and deflecting the laser beam to swing repeatedly along the linear zone, (c) means for transporting a light-sensitive sheet medium to pass through said linear zone, (d) detecting means for detecting an arrival o the leading edge of the sheet medium at said linear zone, and (e) beam modulating means for modulating the laser beam to be generated by said laser beam generating means, said beam modulating means being operative to modulate the laser beam depending on the image to be recorded on a leading portion of a light-sensitive sheet medium before said detecting means detects that the leading edge of the light-sensitive sheet medium which has been advancing toward said linear zone reaches the linear zone and to modulate the laser beam depending on the images to be recorded on a portion subsequent to said leading portion of the light-sensitive sheet medium after said detecting means detects that the leading edge of the light-sensitive sheet medium advanced toward said linear zone has reached the linear zone.
Claim 15
Dependent Claim 210 words
A laser-beam image recording apparatus for recording images on a light-sensitive sheet medium through irradiation of an information-carrying laser beam, comprising (a) laser beam generating means for emitting a laser beam, (b) deflecting means for directing said laser beam toward a linear zone and deflecting the laser beam to swing repeatedly along the linear zone, (c) means for transporting a light-sensitive sheet medium to pass through said linear zone, (d) detecting means for detecting an arrival o the leading edge of the sheet medium at said linear zone, and (e) beam modulating means for modulating the laser beam to be generated by said laser beam generating means, said beam modulating means being operative to modulate the laser beam depending on the image to be recorded on a leading portion of a light-sensitive sheet medium before said detecting means detects that the leading edge of the light-sensitive sheet medium which has been advancing toward said linear zone reaches the linear zone and to modulate the laser beam depending on the images to be recorded on a portion subsequent to said leading portion of the light-sensitive sheet medium after said detecting means detects that the leading edge of the light-sensitive sheet medium advanced toward said linear zone has reached the linear zone.
Claim 16
Dependent Claim 61 words
A laser-beam image recording apparatus as set forth in claim 13, in which said detecting means comprises a sensor for producing an output signal responsive to the laser beam incident on said linear zone, the detecting means being operative to detect the arrival of the leading edge of the sheet medium at said linear zone on the basis of said signal.
Claim 17
Dependent Claim 109 words
A laser-beam image recording apparatus as set forth in claim 14, in which said sensor is located to receive a laser beam directed to a predetermined location with respect to the direction in which the laser beam is incident on said linear zone, said beam modulating means being operative to modulate the laser beam such that the laser beam generating means generates a laser beam at least at a timing at which the laser beam is to pass through said predetermined location before the leading edge of a light-sensitive sheet medium is detected to have reached said linear zone while a laser beam is swinging along said linear zone.
Claim 18
Dependent Claim 65 words
A laser-beam image recording apparatus as set forth in claim 13, in which said deflecting means comprises a rotatable polygonal mirror located to receive a laser beam from said laser beam generating means and re-direct the incident laser beam toward said linear zone, the laser beam incident on the linear zone being deflected to swing repeatedly along the linear zone as said polygonal mirror rotates.
Claim 19
Dependent Claim 45 words
A laser-beam image recording apparatus as set forth in claim 13, in which said laser beam generating means comprises a semiconductor laser radiation element and in which said beam modulating means is operative to control an electric signal to activate said semiconductor laser radiation element.
Claim 20
Dependent Claim 77 words
A laser-beam image recording apparatus as set forth in claim 14, in which said sensor is located to receive a laser beam reflected from a light-sensitive sheet medium extending through said linear zone and in which said control means is operative to control said laser beam generating means so that the generated by the laser beam generating means is directed to said sensor only in the presence of a light-sensitive sheet medium extending through said linear zone.
Claim 21
Dependent Claim 79 words
A laser-beam image recording apparatus as set forth in claim 18, in which said deflecting means and said linear zone are arranged so that, in the presence of a light-sensitive sheet medium extending through said linear zone, a laser beam generated by said laser beam generating means is incident on the light-sensitive sheet at a predetermined angle less than 90 degrees with respect to a plane normal to the surface of the sheet medium extending through the linear zone.
Claim 22
Dependent Claim 114 words
A laser-beam image recording apparatus as set forth in claim 18, in which said transport means comprises a support member having a light-absorptive surface for receiving thereon a light-sensitive sheet medium extending through said linear zone so that, in the presence of a light-sensitive sheet medium extending through said linear zone, a laser beam directed toward said linear zone is reflected from the surface of the light-sensitive sheet medium and re-directed toward said sensor and, in the absence of a light-sensitive sheet medium extending through said linear zone, a laser beam directed toward said linear zone is absorbed in the light-absorptive surface of said support member and is substantially not re-directed toward said sensor.
Claim 23
Dependent Claim 58 words
A laser-beam image recording apparatus as set forth in claim 20, in which said support member consists of a cylindrical drum having a center axis and rotatable about the center axis for transporting a light-sensitive sheet medium received on the peripheral surface thereof, said light-absorptive surface of said support member comprising the peripheral surface of said cylindrical drum.
Claim 24
Dependent Claim 70 words
A laser-beam image recording apparatus as set forth in claim 20, in which said sensor is located, in a direction in which a laser beam is to be directed toward said linear zone, beyond a plane containing said linear zone so that a laser beam directed toward said linear zone is allowed to reach said sensor only in the absence of a light-sensitive sheet medium extending through said linear zone.
Claim 25
Dependent Claim 276 words
A laser-beam image recording apparatus for recording images on a light-sensitive sheet medium through irradiation of an information-carrying laser beam modulated depending on the image to be recorded by the beam, comprising (a) laser beam generating means for emitting a laser beam, (b) means for directing said laser beam toward a linear zone and deflecting the laser beam to swing repeatedly along the linear zone, (c) means for transporting a light-sensitive sheet medium to pass through said linear zone, (d) detecting means for detecting an arrival of the leading edge of the sheet medium at said linear zone, said detecting means including a sensor for producing an output signal responsive to the laser beam directed to a predetermined location with respect to the direction in which the laser beam is incident on said linear zone, the detecting means being operative to detect the arrival of the leading edge of the sheet medium at said linear zone on the basis of said signal, and (e) control means for controlling said laser beam generating means, said control means being operative to control said laser beam generating means such that the laser beam is generated by the laser beam generating means at a timing at which the laser beam incident in said linear zone reaches said predetermined point before said detecting means detects that the leading edge of a light-sensitive sheet medium which has been advancing toward said linear zone reaches the linear zone and that laser beam generating means generates said information-carrying laser beam after said detecting means detects that the leading edge of the light-sensitive sheet medium advanced toward said linear zone has reached the linear zone.
Claim 26
Dependent Claim 276 words
A laser-beam image recording apparatus for recording images on a light-sensitive sheet medium through irradiation of an information-carrying laser beam modulated depending on the image to be recorded by the beam, comprising (a) laser beam generating means for emitting a laser beam, (b) means for directing said laser beam toward a linear zone and deflecting the laser beam to swing repeatedly along the linear zone, (c) means for transporting a light-sensitive sheet medium to pass through said linear zone, (d) detecting means for detecting an arrival of the leading edge of the sheet medium at said linear zone, said detecting means including a sensor for producing an output signal responsive to the laser beam directed to a predetermined location with respect to the direction in which the laser beam is incident on said linear zone, the detecting means being operative to detect the arrival of the leading edge of the sheet medium at said linear zone on the basis of said signal, and (e) control means for controlling said laser beam generating means, said control means being operative to control said laser beam generating means such that the laser beam is generated by the laser beam generating means at a timing at which the laser beam incident in said linear zone reaches said predetermined point before said detecting means detects that the leading edge of a light-sensitive sheet medium which has been advancing toward said linear zone reaches the linear zone and that laser beam generating means generates said information-carrying laser beam after said detecting means detects that the leading edge of the light-sensitive sheet medium advanced toward said linear zone has reached the linear zone.
Claim 27
Dependent Claim 65 words
A laser-beam image recording apparatus as set forth in claim 23, in which said deflecting means comprises a rotatable polygonal mirror located to receive a laser beam from said laser beam generating means and re-direct the incident laser beam toward said linear zone, the laser beam incident on the linear zone being deflected to swing repeatedly along the linear zone as said polygonal mirror rotates.
Claim 28
Dependent Claim 44 words
A laser-beam image recording apparatus as set forth in claim 23, in which said laser beam generating means comprises a semiconductor laser radiation element and in which said control means is operative to control an electric signal to activate said semiconductor laser radiation element.
Claim 29
Dependent Claim 77 words
A laser-beam image recording apparatus as set forth in claim 23, in which said sensor is located to receive a laser beam reflected from a light-sensitive sheet medium extending through said linear zone and in which said control means is operative to control said laser beam generating means so that the generated by the laser beam generating means is directed to said sensor only in the presence of a light-sensitive sheet medium extending through said linear zone.
Claim 30
Dependent Claim 79 words
A laser-beam image recording apparatus as set forth in claim 26, in which said deflecting means and said linear zone are arranged so that, in the presence of a light-sensitive sheet medium extending through said linear zone, a laser beam generated by said laser beam generating means is incident on the light-sensitive sheet at a predetermined angle less than 90 degrees with respect to a plane normal to the surface of the sheet medium extending through the linear zone.
Claim 31
Dependent Claim 114 words
A laser-beam image recording apparatus as set forth in claim 26, in which said transport means comprises a support member having a light-absorptive surface for receiving thereon a light-sensitive sheet medium extending through said linear zone so that, in the presence of a light-sensitive sheet medium extending through said linear zone, a laser beam directed toward said linear zone is reflected from the surface of the light-sensitive sheet medium and re-directed toward said sensor and, in the absence of a light-sensitive sheet medium extending through said linear zone, a laser beam directed toward said linear zone is absorbed in the light-absorptive surface of said support member and is substantially not re-directed toward said sensor.
Claim 32
Dependent Claim 58 words
A laser-beam image recording apparatus as set forth in claim 28, in which said support member consists of a cylindrical drum having a center axis and rotatable about the center axis for transporting a light-sensitive sheet medium received on the peripheral surface thereof, said light-absorptive surface of said support member comprising the peripheral surface of said cylindrical drum.
Claim 33
Dependent Claim 70 words
A laser-beam image recording apparatus as set forth in claim 23, in which said sensor is located, in a direction in which a laser beam is to be directed toward said linear zone, beyond a plane containing said linear zone so that a laser beam directed toward said linear zone is allowed to reach said sensor only in the absence of a light-sensitive sheet medium extending through said linear zone.

References Cited (Backward Citations)

US4292529A Cited
US4494130A Cited
JPS5831662A Cited
US4532429A Cited
US4617470A Cited
JPS5876853A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-11-13 1993-05-15 1993-11-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-11-13 1997-05-15 1997-11-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-11-13 2001-05-15 2001-11-14 $7700.00 Window Closed / Lapsed

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