Portable data collection device with variable focusing module for optic assembly

• US 6,431,452 B2
• Filed: 01/30/2001
• Issued: 08/13/2002
• Est. Priority Date: 01/31/1997
• Status: Expired due to Term

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Metanetics Corporation
• Inventors: Feng, Chen
• Primary Examiner(s): Lee, Michael G.
• Assistant Examiner(s): St. Cyr, Daniel
• Application Number:
  US09/772,358
• Publication Number:
  US 20010003346A1
• Time in Patent Office: 560 Days
• Field of Search: 235/462.09, 235/462.01, 235/462.24, 235/462.25, 235/462.45, 235/472.01
• US Class Current: 235/472.01
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources

Abstract

A portable data collection device including an imaging assembly including a two dimensional (2D) photosensor array. The imaging assembly is selectively actuatable with a first trigger for reading a target dataform in the imaging assembly'"'"'s target area and actuatable with a second trigger for capturing a image of the target object in the target area. The device also includes an illumination assembly including an circuit board assembly supporting illumination and targeting light emitting diodes and a lens array or panel positioned adjacent the circuit board assembly for focusing an even pattern of illumination on the target area and generating a crosshair illumination pattern for aiming the device at the target dataform. The device further includes an optic assembly for focusing reflected illumination from the target area onto the two dimensional photosensor array. The optic assembly includes a focusing optic for changing a best focus distance of the optic assembly as a function of moving a wedge shaped optic with respect to a stationary optic to change a thickness of the focusing optic.

Claims

1. A portable data collection device comprising:

a) a camera assembly, including an array of photosensor elements generating a signal representative of an image of a target area, the image including a dataform positioned in the target area; and

b) an optic assembly positioned to focus illumination reflected from a generally rectangular target area onto the array of photosensor elements, the optic assembly including a focusing optic through which reflected illumination from the target area passes, the focusing optic including a movable lens movable along a path of travel transverse to a central ray of the reflected illumination passing through the optic assembly, movement of the movable lens changing a best focus distance of the optic assembly wherein the best focus distance corresponds to a distance between the device and the dataform which results in a clear image of the dataform being focused onto the array of photosensor elements.

2. The portable data collection device of claim 1 wherein the focusing optic includes the moveable lens and a stationary lens configured such that moving the moveable lens with respect to the stationary lens along the path of travel of the moveable lens changes the thickness of the focusing optic through which the reflected light passes and correspondingly changes the best focus distance.

3. The portable data collection device of claim 2 wherein the moveable lens and the stationary lens are comprised of wedge shaped pieces of glass each having an inclined surface and wherein the inclined surfaces are in sliding contact.

4. The portable data collection device of claim 3 wherein the focusing optic is part of a focusing assembly which includes structure operatively connected to the moveable optic to move the moveable lens along its path of travel.

5. The portable data collection device of claim 1 further including an illumination assembly directing illumination towards the target area, the illumination assembly including a targeting arrangement for directing an illumination targeting pattern aid in aiming the portable data collection device, the targeting arrangement including first and second targeting light emitting diodes and first and second targeting optics, the first targeting optics positioned adjacent the first targeting light emitting diode and generating a first illumination targeting pattern and the second targeting optics positioned adjacent the second targeting light emitting diode and generating a second illumination targeting pattern, the first and second targeting pattern substantially coinciding to form a single illumination targeting pattern when the device is at a minimum distance best focus position.

6. The portable data collection device of claim 5 wherein the first targeting optics includes a light entry optic surface facing the first targeting light emitting diode and a light exit optic surface directed toward the target area and wherein the second targeting optics includes a light entry optic surface facing the second targeting light emitting diode and a light exit optic surface directed toward the target area and further wherein the light entry optic surfaces of each of the first and second targeting optics comprise aspheric optic surfaces.

7. The portable data collection device of claim 6 wherein the light exit optic surface of each of the first and second targeting optics comprise a plurality of cylindrical surfaces.

8. The portable data collection device of claim 5 wherein the first and second targeting optics are supported in a panel having a generally planar front surface which faces the target area and wherein the light exit optic surface of each of the first and second targeting optics is tilted with respect to the generally planar front surface of the panel.

9. The portable data collection device of claim 8 wherein an angle of tilt of the first targeting optics light exit optic surface with respect to the generally planar front surface of the panel is substantially equal to an angle of tilt of the second targeting optics light exit optic surface with respect to the generally planar front surface of the panel.

10. The portable data collection device of claim 9 wherein the first targeting optics light exit optic surface comprises first and second vertically oriented cylindrical optic surfaces and first and second horizontally oriented cylindrical optic surfaces and wherein the targeting pattern generated by the first targeting optics is a crosshair pattern and further wherein the second targeting optics light exit optic surface comprises first and second vertically oriented cylindrical optic surfaces and first and second horizontally oriented cylindrical optic surfaces and wherein the targeting pattern generated by the second targeting optics is a crosshair pattern.

11. The portable data collection device of claim 1 further including image processing and decoder circuitry receiving the signal representative of the image of the target area and generating decoded data representative of the dataform.