Apparatus and method for automatically detecting and optically scanning graphic matter

• US 5,929,435 A
• Filed: 07/03/1996
• Issued: 07/27/1999
• Est. Priority Date: 07/03/1996
• Status: Expired due to Term

• Current Assignee: Microtek International Incorporated (Zoetis Incorporated)
• Original Assignee: Microtek International Incorporated (Zoetis Incorporated)
• Inventors: Han, Loi
• Primary Examiner(s): LE, QUE TAN
• Application Number:
  US08/678,434
• Time in Patent Office: 1,119 Days
• Field of Search: 250/234, 250/559.4, 250/559.06, 250/559.36, 358/475, 358/256, 358/486, 358/488, 358/474, 382/319
• US Class Current: 250/234
• CPC Class Codes: H04N 1/00795 Reading arrangements details of scanning heads H04N1/024; scanning arrangements therefor H04N1/04
• CPC Class Codes: H04N 1/00803 Presence or absence of information

Abstract

An optical scanning apparatus for retrieving digital electronic images representative of opaque objects. The apparatus is equipped with a reflective scanning platform for supporting an opaque object thereon. A scanning camera, equipped with a light source for illuminating the platform, is aligned to retrieve images from objects placed upon the reflective scanning platform. An object sensor included with the scanning camera detects the presence of such images. Using the sensor during scanning, provides automotive detection of the end of the object thereby reducing the scan time.

Claims

1. An optical scanning apparatus comprising:

a reflective scanning platform;

a carriage including a surface, and mounted within a scanner housing and adapted for reciprocating movement along a line extending in a first direction parallel to the longitudinal centerline of the scanner;

a scanning camera having an opto-electrical transducer positioned proximate to said reflective scanning platform and adapted for movement relative to said platform and in a predetermined direction;

a first light source mounted on said scanning camera proximate the reflective platform and adapted to illuminate a first region of said platform along in the field of view of the scanning camera;

a control circuit connected in circuit with said scanning camera;

a second light source, mounted on said carriage, coupled to said scanning camera and adapted to illuminate a second region of said platform that is in front of the field of view of the scanning camera in the direction of movement;

an object sensor mounted on said scanning camera and adapted to sense light reflected back from said second region; and

said control circuit including a discriminator circuit electrically connected to said sensor and said control circuit.

2. An optical scanning apparatus as set forth in claim 1 wherein said object sensor is an optical sensor aligned to detect light from said light source and reflected off an object placed upon said reflective scanning platform.

3. An optical scanning apparatus as set forth in claim 2 wherein:

said object sensor, in response to the presence of said object placed upon said reflective scanning platform, being operative to generate a sensor signal representative of the presence of said object.

4. An optical scanning apparatus as set forth in claim 3 wherein:

said control circuit in response to said sensor signal, being operative to determine said sensor signal is representative of the presence of said object upon said reflective scanning platform.

5. An optical scanning apparatus as set forth in claim 1 wherein said control circuit includes:

said discriminator circuit to discriminate between an object sensor signal from said object sensor and a threshold value;

means for checking for the presence of an object;

means for scanning said object incrementally; and

means for detecting the end of said object.

6. An optical scanning apparatus as set forth in claim 1 wherein said optical sensor is aligned with said reflective platform and said light source such that upon an object being placed upon said reflective platform, light from said light source is received by said optical sensor by reflection off the object.

7. An optical scanning apparatus as set forth in claim 1 for scanning an object placed upon said reflective platform wherein said optical sensor is operative to receive light generated by said light source and reflected from said object.

8. An optical scanning apparatus as set forth in claim 1 wherein said object sensor positioned on said scanning camera is in spaced apart relation to said opto-electrical transducer.

9. An optical scanning apparatus as set forth in claim 8 including:

means for incrementally moving said scanning camera relative to said reflective platform; and

said optical sensor being moved in spaced apart relation to said opto-electrical transducer.

10. An optical scanning apparatus as set forth in claim 9 including:

a scanner lid operatively attached to said scanner to selectively overlie said reflective platform and having a surface with light absorbing properties.

11. An optical scanning apparatus as set forth in claim 10 wherein said control circuit includes:

means for checking for the presence of an object;

means for scanning said object incrementally; and

means for detecting the end of said object.

12. An optical scanning apparatus as set forth in claim 11 wherein said control circuit further includes:

means for incrementally scanning said object subsequent to detecting the end of said object.

13. An optical scanning apparatus as set forth in claim 12 wherein said object sensor is centered width-wise on said scanning camera.

14. An optical scanning apparatus as set forth in claim 13 wherein said object sensor includes a light emitting diode.

15. An optical scanning apparatus as set forth in claim 14 wherein said object sensor is mounted on the leading portion of said scanning camera.

16. An optical scanning apparatus for scanning an object comprising:

a scanner housing;

a scanning reflective platform formed in the upper surface of said scanner housing;

a cover having a relatively non-reflective region and a relatively reflective region and adapted to cover objects places on said platform;

a scanning camera having a CCD and positioned proximate to said reflective scanning platform;

at least one light source coupled to said scanning camera;

a control circuit connected in circuit with said scanning camera; and

an object sensor mounted on said scanning camera in spaced apart relation to said CCD, adapted to sense light generated by said light source and reflected from the relatively non-reflective region of said cover and connected in circuit with said control circuit;

whereby in response to a first light reflection from said object placed upon said reflective scanning platform, a first signal is generated, and in response to a second light reflection from said relatively non-reflective region, a second signal is generated, when said first light reflection has greater luminance than the second light reflection.

17. An optical scanning apparatus for scanning of an object comprising:

a reflective scanning platform;

a carriage adapted for linear motion beneath said platform;

a scanning camera positioned on said carriage, proximate to said reflective scanning platform and adapted to detect reflections from said reflective platform that have been reflected from at least one mirror positioned in a light path between said platform and said camera;

a light source coupled to said scanning camera and adapted to illuminate a first region of said platform;

a CPU connected in circuit with said scanning camera;

an object sensor mounted on said carriage and adapted to detect reflections directly from said reflective scanning platform and at a time prior to detection of reflection by said camera; and

a discriminator circuit electrically connected to said sensor and said CPU circuit to provide an output signal indicative of the presence or absence of an object to be scanned.

18. An optical scanning apparatus for scanning an object and determining the presence and absence of an object to be scanned comprising:

a reflective scanning platform;

a scanning camera adapted for reciprocating movement in a predetermined direction parallel to the longitudinal centerline of said reflective scanning platform;

at least one light source coupled to said scanning camera and adapted to illuminate said scanning platform;

an object sensor positioned and adapted to sense reflections of light directly through said platform and to generate a first signal indicative of the presence of an object and a second signal indicative of the absence of an object, said first signal and said second signal being proportional to the amount of light reflected;

a control circuit connected in circuit with said scanning camera, in circuit with said object sensor and including means for discriminating between said first signal and said second signal; and

means for scanning said object incrementally and in response to said control circuit upon receipt of said first signal.

19. An optical scanning apparatus for reflective scanning an object, comprising:

a scanner housing;

a scanner lid operatively attached to said scanner housing, having a closed position and including a surface with light absorbing properties;

a reflective scanning platform;

said scanner lid in its closed position overlying said scanning platform;

a scanning camera having a predetermined field of view on said reflective scanning platform;

said scanning camera movable relative to said scanning platform to perform scanning in a scanning direction;

at least one light source coupled to said scanning camera and adapted to illuminate a region of the platform ahead of the field of view in the scanning direction;

a control circuit connected in circuit with said scanning camera and adapted to scan a object when the presence is detected;

an object sensor mounted on said scanning camera and adapted and positioned to generate signals proportional to intensity of light reflected from said platform under said surface and without being reflected from a mirror positioned in a light path between said platform and said camera; and

said control circuit electrically connected to said object sensor and adapted to stop scanning of said object in response to receipt of said signals.

20. An optical scanning method, for implementation of scanning an object and detecting the presence oor absence of the object, in a scanner having at least one light source, an optical object sensor, a scanning camera and a control circuit mounted on a movable carriage and comprising the steps of:

moving said carriage in a line along a first direction from a position ahead of an object positioned on a stationary scanning platform positioned above said carriage to a position behind the object;

generating light from at least one light source and reflecting said light from said stationary scanning platform;

generating object sensor signals in said optical object sensor that are proportional to light reflected through said platform;

discriminating between first object sensor signals and second object sensor signals, the first signals corresponding to relatively low luminance and representative of ambient light reflected from said platform and the second object sensor signals representative of light corresponding to relatively high luminance and reflected from an object;

setting an interrupt flag upon receipt of said object sensor signals being greater than a threshold signal value;

checking for the presence of an object by checking said interrupt flag;

scanning said object incrementally; and

detecting the end of said object.