Imaging based slot dataform reader

• US 5,717,195 A
• Filed: 03/29/1996
• Issued: 02/10/1998
• Est. Priority Date: 03/05/1996
• Status: Expired due to Term

• Current Assignee: Symbol Technologies, LLC (Zebra Technologies Corporation)
• Original Assignee: Metanetics Corporation
• Inventors: Feng, Chen, Wang, Ynjiun P.
• Primary Examiner(s): Hajec, Donald T.
• Assistant Examiner(s): LE, THIEN MINH
• Application Number:
  US08/623,544
• Time in Patent Office: 683 Days
• Field of Search: 235/462, 235/472, 235/454, 235/469, 235/470, 382/59, 382/2
• US Class Current: 235/470
• CPC Class Codes: G06K 7/1093 sensing, after transfer of the image of the data-field to an intermediate store, e.g. storage with cathode ray tube
• CPC Class Codes: G06K 7/14 using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence

Abstract

A fixed position dataform reader reads a dataform printed on a substrate and passed through a desired target area. The reader comprises a housing, a first camera assembly, image processing and decoder circuitry, and a mounting support. The housing has a base surface, a face surface, and at least one side surface interconnecting the base surface to the face surface and defining an interior region. The face surface defines an aperture. The first camera assembly includes a two-dimensional photosensor array supported in the interior region and an optics assembly spaced from the two-dimensional photosensor array to focus an image of the dataform onto the two-dimensional photosensor array. The image processing and decoder circuitry is coupled to the camera assembly for generating decoded data representative of the dataform. The mounting support is secured to the housing for mounting the reader in a fixed position with respect to the desired target area.

Claims

1. A fixed position dataform reader for reading a dataform printed on a substrate and passed through a two-dimensional target area, the reader comprising:

a) a housing having a base surface, a face surface and at least one side surface, interconnecting the base surface to the face surface, defining an interior region, the face surface defining an aperture;

b) a first camera assembly including a two-dimensional photosensor array supported in the interior region and an optics assembly spaced from the two-dimensional photosensor array to focus an image of the two-dimensional target area including the dataform onto the two-dimensional photosensor array, the photosensor array comprising a two-dimensional array of photosensors which are read out after an exposure period to generate a signal representative of an image of the two-dimensional target area including the dataform;

c) an analog to digital converter electrically coupled to the first camera assembly receiving the signal and converting the signal to a plurality of gray scale digital values representative of the image of the two-dimensional target area including the dataform;

d) a memory electrically coupled to the analog to digital converter for storing the plurality of gray scale digital data values;

e) image processing and decoder circuitry coupled to the camera assembly and the memory for determining a set of digital data values from the plurality of gray scale digital values which correspond to an image of the dataform and decoding the set of digital data values to generate decoded data representative of the dataform; and

f) a mounting support, secured to the housing, for mounting the reader in a fixed position with respect to the two-dimensional target area.

2. The fixed position dataform reader of claim 1, comprising a radio transmitter coupled to the signal processing and decoder circuitry for transmitting the decoded data to a remote host.

4. The fixed position dataform reader of claim 1, comprising a first reflective surface positioned in the interior region to redirect at least a portion of a field of view of the camera assembly into at least a portion of the two-dimensional target area.

6. The fixed position dataform reader of claim 4, wherein the first reflective surface is a mirrored surface.

11. The fixed position dataform reader of claim 1 wherein the dataform is a two-dimensional dataform.

3. A fixed position dataform reader for reading a dataform printed on a substrate and passed through a selected one of a first portion of a target area and a second port of the target area, the reader comprising:

a) a housing having a base surface, a face surface and at least one side surface, interconnecting the base surface to the face surface, defining an interior region, the face surface defining an aperture;

b) a first camera assembly including a two-dimensional photosensor array supported in the interior region and an optics assembly spaced from the two-dimensional photosensor array to focus an image of a dataform passed through the first portion of the target area onto the two-dimensional photosensor array;

c) image processing and decoder circuitry coupled to the camera assembly for generating decoded data representative of the dataform;

d) a mounting support, secured to the housing, for mounting the reader in a fixed position with respect to the desired target area; and

e) a second camera assembly including a second two-dimensional photosensor array supported in the housing interior region and a second optics assembly spaced from the second photosensor array to focus an image of a dataform passed through the second portion of the target area onto the second photosensor array.

12. The fixed position dataform reader of claim 3 wherein the dataform is a two-dimensional dataform.

5. A fixed position dataform reader for reading a dataform printed on a substrate and passed through a desired target area, the reader comprising:

a) a housing having a base surface, a face surface and at least one side surface, interconnecting the base surface to the face surface, defining an interior region, the face surface defining an aperture;

b) a first camera assembly including a two-dimensional photosensor array supported in the interior region and an optics assembly spaced from the two-dimensional photosensor array to focus an image of the dataform onto the two-dimensional photosensor array;

c) image processing and decoder circuitry coupled to the camera assembly for generating decoded data representative of the dataform; and

d) a mounting support, secured to the housing, for mounting the reader in a fixed position with respect to the desired target area; and

e) a first reflective surface positioned in the housing interior region to redirect at least a portion of a field of view of the camera assembly into at least a portion of the target area and a second reflective surface positioned in the housing interior region to redirect a second portion of the field of view into another portion of the target area.

7. The fixed position dataform reader of claim 5, wherein the first and second reflective surfaces are mirrored surfaces.

13. The fixed position dataform reader of claim 5 wherein the dataform is a two-dimensional dataform.

8. A method of completing a sales transaction for the sale of a plurality of items, each item including a dataform including encoded data identifying the item, the method comprising:

a) mounting at a fixed position a dataform reader including a camera assembly, a two-dimensional photosensor array comprising a two-dimensional array of photosensors, and an optic assembly for focusing an image of a two-dimensional target area onto the photosensor array;

b) passing a dataform of an item through the two-dimensional target area to focus an image of the two-dimensional target area including the dataform onto the two-dimensional photosensor array;

c) reading out the array of photosensors of the two-dimensional photosensor array after an exposure period to generate a signal representative of an image of the two-dimensional target area including the dataform;

d) converting the signal to a plurality of digital image data values representative of the image of the two-dimensional target area including the dataform;

e) storing the digital image data values in a memory;

f) processing the digital image data values stored in memory to determine a set of digital image data values corresponding to an image of the dataform;

g) decoding the set of digital image data values to generate decoded data identifying the item;

h) retrieving a price for the item corresponding to the decoded data identifying the item; and

i) repeating the steps (b) through (h) for each item.

9. The method of claim 8, wherein step (h) includes a substep of transmitting a representation of the decoded data by radio to a host terminal.

10. The method of claim 8 wherein the dataform in a two-dimensional dataform.