Image reading apparatus having a light source including a fluorescent lamp

• US 6,118,555 A
• Filed: 03/01/1996
• Issued: 09/12/2000
• Est. Priority Date: 03/02/1995
• Status: Expired due to Fees

• Current Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Original Assignee: Canon Ayutthaya Limited (Canon Inc.)
• Inventors: Sasaki, Kenichi, Matsuoka, Kazuhiko, Sugiyama, Miho
• Primary Examiner(s): Williams, Kimberly A.
• Application Number:
  US08/609,058
• Time in Patent Office: 1,656 Days
• Field of Search: 358/505, 358/506, 358/509, 358/474, 358/475, 358/487, 358/494, 358/500, 399/220, 399/221, 355/67, 362/260, 313/110, 313/111, 313/112, 250/208.1
• US Class Current: 358/475
• CPC Class Codes: H04N 1/02815 Means for illuminating the original, not specific to a particular type of pick-up head
• CPC Class Codes: H04N 1/0285 in combination with at least one reflector which is in fixed relation to the light source
• CPC Class Codes: H04N 1/0287 using a tubular lamp or a combination of such lamps

Abstract

In an image reading apparatus provided with a light source for illuminating an original, the light source includes a fluorescent lamp having a tube surface by means of which a part of a beam of light therefrom is condensed on the surface of the original by the optical action thereof, a line sensor for reading image information of the original and an optical device for causing image information of the original illuminated with the beam of light from the light source to be imaged on the line sensor.

Claims

1. An image reading apparatus comprising:

light source means for illuminating an original, said light source means including a cathode tube of which a tube surface thereof opposed to a surface of the original comprises a flat surface, wherein the cathode tube has a fluorescent flat surface;

reading means; and

imaging means for causing image information of the original illuminated with a beam of light from said light source means to be imaged on said reading means.

2. An image reading apparatus according to claim 1, wherein the original is a transmission type original.

3. An image reading apparatus according to claim 1, wherein said reading means comprises a line sensor in which a plurality of picture elements are one-dimensionally arranged in a main scanning direction.

4. An image reading apparatus according to claim 1, wherein said reading means comprises a three-line sensor in which three line sensors, each of which includes a plurality of picture elements one-dimensionally arranged in a main scanning direction, are juxtaposed in a sub scanning direction.

5. An image reading apparatus according to claim 1, wherein said reading means comprises an area sensor in which a plurality of picture elements are two-dimensionally arranged in a main scanning direction and in a sub scanning direction.

6. An image reading apparatus comprising:

light source means for illuminating an original, said light source means including a tube surface of which a cross-sectional shape thereof facing a surface of the original comprises a flat surface with respect to a main scanning direction and a concave surface with respect to a sub scanning direction;

reading means; and

imaging means for causing image information of the original illuminated with a beam of light from said light source means to be imaged on said reading means.

7. An image reading apparatus according to claim 6, wherein said light source means includes a fluorescent lamp, and an inner surface of the tube surface thereof facing the surface of the original has a fluorescent material applied thereto.

8. An image reading apparatus according to claim 7, wherein the fluorescent material is applied to a surface inside the fluorescent lamp opposed to the inner surface.