Claims
- 1. In a scanning mechanism: means for providing a beam of high intensity light,
- a medium,
- a start of scan detector located spatially from said medium,
- means for imaging said beam to a spot at said medium and at said scan detector,
- scanning means positioned in the optical path of said beam for scanning said beam across said medium,
- means optically located between said scanning means and said medium in the path of said scanned beam for deflecting a portion of the scanned beam to said scan detector,
- said imaging means comprising first and second cylindrical lenses,
- said first cylindrical lens being optically located between said medium and said scanning means and in the path of only the scanned beam directed to said medium,
- said second cylindrical lens being optically located between said deflecting means and said start of scan detector and in the path of only the deflected scanned beam,
- said first and second cylindrical lenses being so positioned in the path of the scanned beam that runout errors are substantially corrected at said medium and said scan detector, the plane of no power of said cylindrical lenses being oriented in the direction of scan,
- said second cylindrical lens being positioned from said start of scan detector at substantially the same optical distance said first cylindrical lens is positioned from said medium, and
- said second cylindrical lens being optically matched with said first cylindrical lens and having substantially the same focal length and aperture as said first cylindrical lens.
- 2. The structure as recited in claim 1 further comprising: means for modulating said light beam, said medium being a light sensitive medium.
- 3. The system as defined in claim 1 wherein the scanning means includes a multifaceted polygon having reflective sides for reflecting the beam onto said medium and means for rotating said polygon such that the reflected beam is scanned in successive traces across said medium.
- 4. The system as defined in claim 3 wherein said light source is a laser which emits a beam of collimated light of substantially uniform intensity.
- 5. The structure as recited in claim 4 further comprising: means for modulating said light beam, said medium being a light sensitive medium.
RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 625,219, filed Oct. 23, 1975, now abandoned, which in turn is a continuation of U.S. application Ser. No. 309,873, filed Nov. 27, 1972, now abandoned.
US Referenced Citations (8)
Non-Patent Literature Citations (3)
Entry |
"Laser Raster Scanner with Separated Incident and Reflected Beams;" by D. H. McMurtry; IBM Tech. Disc. Bul.; vol. 14, No. 8, Jan., 1972, pp. 2460-2461. . |
"Laser Raster Scanner;" by M. R. Latta; IBM Tech. Disc. Bul.; vol. 13, No. 12, May, 1971; pp. 3879-3880. |
"Optical Deflector For Non Impact Printing;" by Brown et al; IBM Tech. Disc. Bul.; vol. 13, No. 3, Aug. 1970; pp. 643-644. |
Continuations (2)
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Number |
Date |
Country |
Parent |
625219 |
Oct 1975 |
|
Parent |
309873 |
Nov 1972 |
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