Optical data reader with control mechanism implemented behind the window

• US 6,917,723 B1
• Filed: 04/25/2000
• Issued: 07/12/2005
• Est. Priority Date: 04/25/2000
• Status: Expired due to Term

• Current Assignee: PSC Scanning, Inc. (Datalogic ADC Incorporated)
• Original Assignee: PSC Scanning, Inc. (Datalogic ADC Incorporated)
• Inventors: Tamburrini, Thomas E., Schler, Matt D.
• Primary Examiner(s): Do, Anh Hong
• Application Number:
  US09/557,637
• Time in Patent Office: 1,904 Days
• Field of Search: 382/317, 382/321, 340/555, 340/674, 340/511, 235/462.25, 235/472.01, 235/462.45, 235/440, 235/445
• US Class Current: 382/317
• CPC Class Codes: G06K 2207/1012 Special detection of object
• CPC Class Codes: G06K 7/10851 Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device basic electronic circuitry H03

Abstract

In an optical data reader, light is aimed out through a window at objects located in front of the window, and reflections from the objects and/or the window itself are detected. The amount of detected light is compared to one or more expected levels to determine when an object is present in front of the window and/or whether the window is properly installed. The optical reader is controlled based on this determination. Control functions that may be implemented in this manner include, for example, waking up the data reader when an object is detected in front of the glass, and disabling the data reader if the window is removed.

Claims

1. A method of controlling a data reader, the method comprising the steps of:

illuminating an object located immediately in front of a specific portion of a window with light from a light source;

detecting an amount of light from the light source that has been reflected by the object;

determining whether an object is present or absent from immediately in front of the specific portion of the window by comparing the amount of light detected in the detecting step to an amount of light expected when an object is present immediately in front of the specific portion of the window; and

initiating a data reader control function in response to a determination made in the determining step.

2. The method of claim 1, wherein, the data reader control function is initiated in the initiating step when it is determined, in the determining step, that an object is present immediately in front of the specific portion of the window.

3. The method of claim 1, wherein, the data reader control function is initiated in the initiating step when it is determined, in the determining step, that an object is absent from immediately in front of the specific portion of the window.

4. The method of claim 1, wherein, in the determining step, the determination that the object is present immediately in front of the specific portion of the window is made when an operator'"'"'s hand is present in an immediate vicinity of the specific portion of the window.

5. The method of claim 4, wherein the control function comprises a volume control function.

6. The method of claim 4, wherein the control function comprises a wake-up function.

7. The method of claim 1, wherein, in the determining step, the determination that the object is present immediately in front of the specific portion of the window is made when an operator'"'"'s hand is present in a general vicinity of the specific portion of the window.

8. The method of claim 7, wherein the control function comprises a wake-up function.

9. The method of claim 1 wherein the specific region of the window includes markings on the face of the window identifying an active region, wherein the object comprises an operator'"'"'s hand being positioned in front of the specific portion of the window for initiating a data reader control function.

10. A method of controlling a data reader, the method comprising the steps of:

illuminating an object located in front of a window with light from a light source;

detecting an amount of light from the light source that has been reflected by the object;

determining whether an object is present or absent from in front of the window by comparing the amount of light detected in the detecting step to an amount of light expected when an object is present in front of the window; and

initiating a data reader control function in response to a determination made in the determining step,

wherein, in the determining step, a first determination is made when the object is present in an immediate vicinity of the window, and a second determination is made when the object is present in a general vicinity of the window, and

wherein, in the initiating step, a first data reader control function is initiated when the first determination is made in the determining step, and a second data reader control function is initiated when the second determination is made in the determining step.

11. The method of claim 10, wherein the first control function comprises a volume control function, and the second control function comprises a wake-up function.

12. A method of controlling a data reader having a window, the method comprising the steps of:

illuminating the window with light from a light source;

detecting an amount of light from the light source that has been reflected by the window;

determining whether the window is present by comparing the amount of light detected in the detecting step to an amount of light expected when a window is present; and

disabling the data reader if it is determined, in the determining step, that the window is not present.

13. The method of claim 12, wherein the data reader includes a laser, and the step of disabling the data reader comprises the step of turning the laser off.

14. An apparatus comprising:

a window having a first region;

a light source positioned behind the window, aimed to illuminate an object located in front of the window;

a first light detector positioned behind the window, aimed to detect light from the light source that has been reflected by the object;

a first comparator that compares an amount of light detected by the first light detector to a first threshold, and asserts a first output when the amount of light detected by the first light detector exceeds a first threshold; and

an optical data reader having a second light detector, the second light detector positioned behind the window and aimed to detect light arriving from objects located in front of the window, wherein the optical data reader is controlled by an assertion of the first output.

15. The apparatus of claim 14, wherein the amount of light detected by the first-light detector exceeds the first threshold when an object is present in front of the window in an immediate vicinity of the first region of the window.

16. The apparatus of claim 15, wherein the optical data reader adjusts a volume in response to the assertion of the first output.

17. The apparatus of claim 15, wherein the optical data reader initiates a wake-up function in response to the assertion of the first output.

18. The apparatus of claim 15, wherein the optical data reader is controlled by the assertion of the first output when the assertion of the first output continues for at least one second.

19. The apparatus of claim 14, wherein the amount of light detected by the first light detector exceeds the first threshold when an object is present in front of the window in a general vicinity of the window.

20. The apparatus of claim 19, wherein the optical data reader initiates a wake-up function in response to the assertion of the first output.

21. The apparatus of claim 14, wherein the amount of light detected by the first light detector exceeds the first threshold when the window is installed in front of the light source and the first light detector, and

wherein the optical data reader is disabled when the first output is not asserted.

22. The apparatus of claim 21, wherein the optical data reader comprises a laser, and the laser is turned off when the optical data reader is disabled.

23. The apparatus of claim 14, further comprising a second comparator that compares the amount of light detected by the first light detector to a second threshold, and asserts a second output when the amount of light detected by the first light detector exceeds a second threshold, and

wherein the optical data reader is controlled by an assertion of the second output.

24. The apparatus of claim 23, wherein the amount of light detected by the first light detector exceeds the first threshold when an object is present in front of the window in an immediate vicinity of the first region of the window, and the amount of light detected by the first light detector exceeds the second threshold when an object is present in front of the window in a general vicinity of the window.

25. The apparatus of claim 24, wherein the optical data reader adjusts a volume in response to the assertion of the first output, and initiates a wake-up function in response to the assertion of the second output.

26. The apparatus of claim 14, further comprising:

a second comparator that compares the amount of light detected by the first light detector to a second threshold, and asserts a second output when the amount of light

detected by the first light detector exceeds a second threshold; and

a third comparator that compares the amount of light detected by the first light detector to a third threshold, and asserts a third output when the amount of light

detected by the first light detector exceeds a third threshold,

wherein the optical data reader is controlled by an assertion of the first output, and the optical data reader is controlled by an assertion of the second output.

27. The apparatus of claim 26, wherein the amount of light detected by the first light detector exceeds the first threshold when an object is present in front of the window in an immediate vicinity of the first region of the window, the amount of light detected by the first light detector exceeds the second threshold when an object is present in front of the window in a general vicinity of the window, and the amount of light detected by the first light detector exceeds the third threshold when the window is properly installed in the apparatus.

28. The apparatus of claim 27, wherein the optical data reader adjusts a volume in response to the assertion of the first output, wherein the optical data reader initiates a wake-up function in response to the assertion of the second output, and wherein the optical data reader is disabled when the third output is not asserted.

29. The apparatus of claim 14, wherein a single light detector serves as both the first light detector and the second light detector.

30. The apparatus of claim 14, wherein the first light detector and the second light detector are not the same detector.

31. The apparatus of claim 14, wherein the light source includes a modulator that modulates the light generated by the light source, and wherein the light detector includes a discriminator that detects the modulated light and rejects non-modulated light.

32. The apparatus of claim 31, wherein the discriminator comprises a bandpass filter.

33. The apparatus of claim 31, wherein the discriminator comprises a demodulator.

34. The apparatus of claim 31, wherein the modulator comprises a switch that switches the light source on and off, and the discriminator comprises a subtractor that subtracts a light measurement made when the switch is off from a light measurement made when the switch is on.

35. The apparatus of claim 14, further comprising an optical data receiver that, when a wireless optical data transmission arrives at the light detector from a remote device, monitors the output signal generated by the light detector and extracts data contained in the data transmission from the output signal, wherein the extracted data is provided to the optical reader.

36. The apparatus of claim 35, wherein the optical reader uses the extracted data to configure or to reprogram the optical reader.

37. The apparatus of claim 35, further comprising an optical data transmitter that transmits data from the optical reader to the remote device by modulating the light generated by the light source based on the data being transmitted.

38. The apparatus of claim 14, wherein the optical reader comprises a barcode reader.

39. The apparatus of claim 14, wherein the optical reader comprises a flying-spot laser barcode reader.

40. A method of controlling a data reader, the method comprising the steps of:

illuminating an object located in front of a window with light from a light source;

detecting an amount of light from the light source that has been reflected by the object;

determining whether the amount of light detected exceeds a first threshold and initiating a first data reader control function if it is determined that the first threshold is exceeded;

determining whether the amount of light detected exceeds a second threshold and initiating a second data reader control function if it is determined that the second threshold is exceeded.

41. A method according to claim 40 wherein the steps of determining comprise simultaneously comparing the amount of light detected to the first and second thresholds.

42. A method according to claim 40 wherein the first data reader control function comprises a wake-up function.

43. A method according to claim 40 wherein the second data reader control function comprises a window detection function.

44. A method according to claim 40 wherein the first threshold is exceeded upon a user placing a hand over the window and first data reader control function comprises a user actuated function.

45. A method according to claim 40 further comprising

determining whether the amount of light detected exceeds a third threshold and initiating a third data reader control function if it is determined that the third threshold is exceeded.