Optical scanning head

• US 5,291,009 A
• Filed: 02/27/1992
• Issued: 03/01/1994
• Est. Priority Date: 02/27/1992
• Status: Expired

• Current Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Original Assignee: Alexander R. Roustaei
• Inventors: Roustaei, Alexander R.
• Primary Examiner(s): PITTS, HAROLD I
• Application Number:
  US07/843,266
• Time in Patent Office: 733 Days
• Field of Search: 235/462, 235/472, 235/466
• US Class Current: 235/462.42
• CPC Class Codes: G03F 7/705 Modelling or simulating from physical phenomena up to complete wafer processes or whole workflow in wafer productions
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10742 including a diffuser for diffusing the light from the light source to create substantially uniform illumination of the target record carrier
• CPC Class Codes: G06K 7/10811 Focalisation
• CPC Class Codes: G06K 7/1092 sensing by means of TV-scanning

Abstract

The ornamental design for a bar code Scanner using the Light Emitting Diode (LED), Optical Scanner assembly and Charge-Coupled Devices (CCD) capable of reading the barcode symbols at the variable distance, as shown and described. The optical passive elements for increasing the depth of field and method of fabricating the scanning head by mass-production techniques are also disclosed.

Claims

1. A device for scanning and decoding information encoded in an optical code, said device comprising:

a printed circuit board having a front, a center, and a rear with a longitudinal centerline bisecting said printed circuit board into a left side and a right side;

a plurality of LEDs disposed on said printed circuit board near said front for projecting light outward from said front, a first portion of said plurality of LEDs disposed on said left side, each LED of said first portion being directed to emit light at a non-zero angle so that its light intersects said longitudinal centerline at an angle different from other LEDs of said first portion, and a second portion disposed on said right side, each LED of said second portion being directed to emit light at a non-zero angle, so that its light intersects said centerline at an angle different from other LEDs of said second portion so that a fan of light is emitted which becomes increasingly broader at greater distances from said plurality of LEDs;

an optic module disposed at said center of said printed circuit board for filtering reflected light which is reflected from the optical code and for focusing said reflected light at a focal plane;

a CCD detector disposed at said rear of said printed circuit board substantially at said focal plane, for receiving said reflected light and generating an electrical signal in response thereto;

a conversion means for converting said electrical signal into a digital signal corresponding to said bar code; and

a voltage source for providing a driving voltage to said plurality of LEDs, said CCD detector and said conversion means.

2. A device as in claim 1 wherein said plurality of LEDs is disposed in a generally "V"-shaped arrangement.

3. A device as in claim 1 wherein said fan of light is projected to form a field of view within which said optical code can be read.

4. A device as in claim 3 wherein said field of view is within the range of zero to 9 inches.

5. A device as in claim 1 wherein said optic module comprises a plurality of lenses disposed within a dark room for shielding out external light.

6. A device as in claim 1 wherein said plurality of LEDs is disposed as close as possible to said window.

7. A device as in claim 1 wherein said plurality of LEDs comprises six LEDs with three LEDs disposed on each of said left side and said right side of said printed circuit board.

8. A device as in claim 5 wherein said plurality of lenses comprises at least two plano-convex lenses and one bi-convex lens disposed along a common optical path.

9. A device as in claim 8 wherein said optic module further comprises at least one optical filter disposed along said common optical path.