Modular omnidirectional bar code symbol scanning system with at least one service port for removable installation of scan module insert

• US 6,874,690 B2
• Filed: 05/03/2002
• Issued: 04/05/2005
• Est. Priority Date: 01/11/2002
• Status: Expired due to Term

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Good, Timothy A., Schmidt, Mark S., Lucera, Mark, Jefferson, Matt
• Primary Examiner(s): LE, THIEN MINH
• Application Number:
  US10/138,936
• Publication Number:
  US 20030141367A1
• Time in Patent Office: 1,068 Days
• Field of Search: 235/462, 235/472, 235/470, 235/454, 235/494
• US Class Current: 235/462.4
• CPC Class Codes: G06K 7/10861 sensing of data fields affixed to objects or articles, e.g. coded labels postal sorting B07C3/14, conveying articles B65G47/48
• CPC Class Codes: G06K 7/1098 the scanning arrangement having a modular construction

Abstract

A modular omnidirectional laser-based bar code symbol scanning system having at least one scan module insert that is removably disposed (e.g., removably installed) within a system housing (or portion thereof) through a service port (e.g., opening) in the system housing (or portion thereof). The scan module insert is a self-contained unit including at least the following components (in addition to mechanical support structures for such components): at least one laser diode, a rotating scanning element, an electric motor that rotates the rotating scanning element, one or more photodetectors, and analog signal processing circuitry that conditions (e.g., amplifies and/or filters out unwanted noise in) the electrical signal produced by the one or more photodetectors. The scan module insert can optionally include additional components including one or more light collecting optical elements, one or more beam folding mirrors, circuitry for detecting and decoding bar code symbols scanned by the system, etc. The modular architecture of omnidirectional laser scanner of the present invention enables quick access to the scan module insert for efficient repair/reconfiguration/configuration of the optical components, electro-optical, electro-mechanical components and/or electrical components integral thereto.

Claims

1. A laser scanning system for reading bar code symbols, said laser scanning system comprising:

a system housing having two scanning windows and two corresponding service ports integral thereto; and

two scan module inserts, each scan module insert being removably disposed within the system housing through a corresponding service port;

wherein each scan module insert projects an omnidirectional laser scanning pattern through one of said scanning windows; and

wherein each said scan module contains components including;

at least one laser diode for producing laser light;

a rotating scanning element for redirecting laser light incident thereon to produce one or more scanning laser beams;

an electric motor for rotating the rotating scanning element;

at least one photodetector for detecting light incident thereon and producing an electrical signal whose amplitude is proportional to the intensity of such detected light; and

analog signal processing circuitry for conditioning the electrical signal produced by the photodetector.

2. A laser scanning system comprising:

a system housing having two scanning windows and two corresponding service ports integral thereto; and

two scan module inserts, each scan module insert being removably disposed within said system housing through a corresponding service port;

wherein each said scan module contains components including;

at least one laser diode for producing laser light;

a rotating scanning element for redirecting laser light incident thereon to produce one or more scanning laser beams;

an electric motor for rotating the rotating scanning element;

at least one photodetector for detecting light incident thereon and producing an electrical signal whose amplitude is proportional to the intensity of such detected light; and

analog signal processing circuitry for conditioning the electrical signal produced by the photodetector; and

wherein components of one of said two scan module inserts contributes to production of a first omnidirectional laser scanning beam projected through one of the two scanning windows,

while components of the other of said two scan module inserts contributes to production of a second omnidirectional laser scanning beam projected through the other one of the two scanning windows.

3. A method of reconfiguring or repairing a laser scanning system, said method comprising the steps of:

(a) providing a system housing having at least one scanning window and at least one service port integral thereto, wherein at least one omnidirectional scanning beam is projected through said scanning window through operation of a first scan module insert, and wherein said first scan module insert is removably disposed within said system housing through said service port, and wherein said first scan module insert includes;

at least one laser diode for producing laser light;

a rotating scanning element for redirecting laser light incident thereon to produce one or more scanning laser beams;

an electric motor for rotating the rotating scanning element;

at least one photodetector for detecting light incident thereon and producing an electrical signal whose amplitude is proportional to the intensity of such detected light; and

analog signal processing circuitry that conditions the electrical signal produced by the photodetector;

(b) providing a second scan module insert, which includes;

at least one laser diode for producing laser light;

a rotating scanning element for redirecting laser light incident thereon to produce one or more scanning laser beams;

an electric motor for rotating the rotating scanning element;

at least one photodetector for detecting light incident thereon and produces an electrical signal whose amplitude is proportional to the intensity of such detected light; and

analog signal processing circuitry for conditioning the electrical signal produced by the photodetector;

(c) removing said first scan module insert from said system housing by passing said first scan module insert through said service port; and

(d) removably installing said second scan module into said system housing through said service port.

4. The method of claim 3, wherein said first and second scan module inserts have different configurations.

6. The method of claim 3, wherein said first and second scan module inserts each further include at least one light collecting optical element, corresponding to the at least one photodetector, that collects returning light (i.e., light from the scanning beam which has been reflected and/or scattered by a bar code label being read) and focuses such returning light onto the corresponding photodetector.

7. The method of claim 3, wherein said first and second scan module inserts each further include at least one beam folding mirror that redirects the scanning laser beam produced by the rotating scanning element through said scanning window, and redirects returning light back toward the rotating scanning element from which it originated.

8. The method of claim 3, wherein said first and second scan module inserts each further include at least one component selected from the group consisting of:

at least one light collecting optical element, corresponding to the at least one photodetector, for collecting returning light (i.e., light from the scanning beam which has been reflected and/or scattered by a bar code label being read) and focuses such returning light onto the corresponding photodetector;

at least one beam folding mirror for redirecting the scanning laser beam produced by the rotating scanning element through said scanning window, and redirects returning light back toward the rotating scanning element from which it originated;

analog-to-digital signal conversion circuitry for converting the analog electric signals produced by the analog signal processing circuitry into digital data signals;

bar code detection circuitry for forming a digitized representation (e.g., a sequence of binary bit values) of a bar code label being read from signals derived from the output of the analog signal processing circuitry;

bar code digitization circuitry for converting the digitized representation of the bar code symbol being read produced by said bar code detection circuitry into a corresponding digital word value;

bar code symbol decode circuitry for decoding the digital word value of the bar code label symbol being read produced by said bar code digitization circuitry to generate character data string values associated therewith;

interface circuitry for formatting one of said digitized representation and said digital word value of the bar code label symbol into a specific output format;

interface circuitry for converting the character data string values of a bar code label into a format suitable for transmission over a communication link to an external host system;

circuitry for communicating the character data string values over a communication link to an external host system;

circuitry for storing the character data string values in persistent memory for subsequent communication to an external host system;

laser drive circuitry for supplying current to the at least one laser diode and controls the output optical power levels of the at least one laser diode;

motor drive circuitry for supplying power to the motor that rotates the rotating scanning element;

a system controller for performing system control operations; and

power supply circuitry, operably coupled to an external power supply, for providing a regulated supply of electrical power to electrical components of the system.

9. The method of claim 3, wherein said first and second scan module inserts each further include two laser diodes and two corresponding photodetectors disposed on opposite sides of said rotating scanning element, in addition to analog signal processing circuitry that conditions the electrical signal produced by the two photodetectors.

10. The method of claim 6, wherein said first and second scan module inserts each further include:

two laser sources and two corresponding photodetectors disposed on opposite sides of said rotating scanning element, in addition to analog signal processing circuitry that conditions the electrical signal produced by the two photodetectors; and

two light collecting optical element corresponding to the two photodetectors disposed on opposite sides of said rotating scanning element.

11. The method of claim 7, wherein said first and second scan module inserts, when mated to the system housing, are each fixably disposed such that the exterior surface of the scan module insert is flush with the exterior surface of the system housing that is adjacent said service port.

12. The method of claim 7, wherein said first and second scan module inserts and the system housing include a mating mechanism that enables the respective scan module insert to be fixably mated and unmated to the system housing such that the respective scan module insert is disposed within the system housing and that also enables spatial registration of optical components mounted within the respective scan module insert to optical components mounted within the system housing.

13. The method of claim 12, wherein said mating mechanism comprises an interlocking flange structure with screw holes, posts and screws.

14. The method of claim 3, wherein a first electrical interconnect is integral to the system housing and is operably coupled to electric components integral thereto, and a second electrical interconnect is integral to each respective scan module insert and is operably coupled to electrical components integral thereto, wherein the first and second electrical interconnects are releasably coupled together to provide an electric connection between the electrical components operably coupled thereto.

15. The method of claim 14, wherein said first electrical interconnect and said second electrical interconnect are fixably mounted to the system housing and respective scan module insert, respectively, in a manner that provides for spatial registration and electrical connection between the two interconnects when the respective scan module insert is mated to system housing.

16. The method of claim 3, wherein said rotating scanning element comprises a rotating polygonal mirror.

17. The method of claim 3, wherein said rotating scanning element comprises a rotating multi-faceted holographic disk.

18. The method of claim 3, wherein the system housing includes two scanning windows and two corresponding service ports integral thereto;

and further comprising the step of providing two scan module inserts that are removably disposed within the system housing through a corresponding service port;

wherein each said scan module insert includes;

at least one laser diode that produces laser light;

a rotating scanning element that redirects laser light incident thereon to produce one or more scanning laser beams;

an electric motor that rotates the rotating scanning element;

at least one photodetector that detects light incident thereon and produces an electrical signal whose amplitude is proportional to the intensity of such detected light; and

analog signal processing circuitry that conditions the electrical signal produced by the photodetector.

5. The method of 3, wherein said first and second scan module inserts each further include at least one component selected from the group consisting of:

at least one light collecting optical element, corresponding to the at least one photodetector, that collects returning light (i.e., light from the scanning beam which has been reflected and/or scattered by a bar code label being read) and focuses such returning light onto the corresponding photodetector; and

at least one beam folding mirror that redirects the scanning laser beam produced by the rotating scanning element through said scanning window, and redirects returning light back toward the rotating scanning element from which it originated.

19. The method of 18, wherein components of one of said two scan module inserts contributes to production of an omnidirectional laser scanning beam projected through one of the two scanning windows, while components of the other of said two scan module inserts contributes to production of an omnidirectional laser scanning beam projected through the other one of the two scanning windows.

20. A bioptical laser scanning system comprising:

a system housing having first and second scanning windows and first and second service ports integral to said system housing, and corresponding to said first and second scanning windows, respectively;

a first scan module insert removably disposed within said system housing through said first service port, and projecting a first omnidirectional laser scanning pattern through said first scanning window;

a second scan module insert removably disposed within said system housing through said second service port, and projecting a second omnidirectional laser scanning pattern through said second scanning window, wherein said first and second omnidirectional laser scanning patterns intersect within 3D scanning volume disposed between said first and second scanning windows, and produce a complex omnidirectonal laser scanning pattern for reading bar code symbols omnidirectionally when presented within said 3D scanning volume; and

wherein said first and second scan module inserts each contain components including;

at least one laser diode for producing laser light;

a rotating scanning element for redirecting laser light incident thereon to produce one or more scanning laser beams;

an electric motor for rotating the rotating scanning element;

at least one photodetector for detecting light incident thereon and producing an electrical signal whose amplitude is proportional to the intensity of such detected light; and

analog signal processing circuitry for conditioning the electrical signal produced by the photodetector.

21. The bioptical laser scanning system of claim 20, wherein the components of said first scan module insert contributes to production of said first omnidirectional laser scanning beam projected through said first scanning window, while the components of said second scan module insert contributes to production of said second omnidirectional laser scanning beam projected through said second scanning window.

22. The bioptical laser scanning system of claim 20, wherein said first and second scan module inserts each further include at least one component selected from the group consisting of:

at least one light collecting optical element, corresponding to the at least one photodetector, that collects returning light (i.e., light from the scanning beam which has been reflected and/or scattered by a bar code label being read) and focuses such returning light onto the corresponding photodetector; and

at least one beam folding mirror that redirects the scanning laser beam produced by the rotating scanning element through the respective scanning window, and redirects returning light back toward the rotating scanning element from which it originated.

23. The bioptical laser scanning system of claim 20, wherein said first and second scan module inserts each further include at least one light collecting optical element, corresponding to the at least one photodetector, that collects returning light (i.e., light from the scanning beam which has been reflected and/or scattered by a bar code label being read) and focuses such returning light onto the corresponding photodetector.

24. The bioptical laser scanning system of claim 20, wherein said first and second scan module inserts each further include at least one beam folding mirror that redirects the scanning laser beam produced by the rotating scanning element through the respective scanning window, and redirects returning light back toward the rotating scanning element from which it originated.

25. The bioptical laser scanning system of claim 20, wherein said first and second scan module inserts each further include at least one component selected from the group consisting of:

at least one light collecting optical element, corresponding to the at least one photodetector, for collecting returning light (i.e., light from the scanning beam which has been reflected and/or scattered by a bar code label being read) and focuses such returning light onto the corresponding photodetector;

at least one beam folding mirror for redirecting the scanning laser beam produced by the rotating scanning element through said scanning window, and redirects returning light back toward the rotating scanning element from which it originated;

analog-to-digital signal conversion circuitry for converting the analog electric signals produced by the analog signal processing circuitry into digital data signals;

bar code detection circuitry for forming a digitized representation (e.g., a sequence of binary bit values) of a bar code label being read from signals derived from the output of the analog signal processing circuitry;

bar code digitization circuitry for converting the digitized representation of the bar code symbol being read produced by said bar code detection circuitry into a corresponding digital word value;

bar code symbol decode circuitry for decoding the digital word value of the bar code label symbol being read produced by said bar code digitization circuitry to generate character data string values associated therewith;

interface circuitry for formatting one of said digitized representation and said digital word value of the bar code label symbol into a specific output format;

interface circuitry for converting the character data string values of a bar code label into a format suitable for transmission over a communication link to an external host system;

circuitry for communicating the character data string values over a communication link to an external host system;

circuitry for storing the character data string values in persistent memory for subsequent communication to an external host system;

laser drive circuitry for supplying current to the at least one laser diode and controls the output optical power levels of the at least one laser diode;

motor drive circuitry for supplying power to the motor that rotates the rotating scanning element;

a system controller for performing system control operations; and

power supply circuitry, operably coupled to an external power supply, for providing a regulated supply of electrical power to electrical components of the system.

26. The bioptical laser scanning system of claim 20, wherein said first and second scan module inserts, when mated to the system housing, are each fixably disposed such that the exterior surface of the scan module insert is flush with the exterior surface of the system housing that is adjacent said service port.

27. The bioptical laser scanning system of claim 20, wherein said first and second scan module inserts and the system housing include a mating mechanism that enables the respective scan module insert to be fixably mated and unmated to the system housing such that the respective scan module insert is disposed within the system housing and that also enables spatial registration of optical components mounted within the respective scan module insert to optical components mounted within the system housing.

28. The bioptical laser scanning system of claim 27, wherein said mating mechanism comprises an interlocking flange structure with screw holes, posts and screws.

30. The bioptical laser scanning system of claim 20, wherein said rotating scanning element comprises a rotating polygonal mirror.

31. The bioptical laser scanning system of claim 20, wherein said rotating scanning element comprises a rotating multi-faceted holographic disk.

32. The bioptical laser scanning system of claim 30, wherein said first electrical interconnect and second electrical interconnect are fixably mounted to the system housing and respective scan module insert, respectively, in a manner that provides for spatial registration and electrical connection between the two interconnects when the respective scan module insert is mates to the system housing.

29. The of bioptical laser scanning system 20, wherein a first electrical interconnect is integral to the system housing and is operably coupled to electric components integral thereto, and a second electrical interconnect is integral to each respective scan module insert and is operably coupled to electrical components integral thereto, wherein the first and second electrical interconnects are releasably coupled together to provide electric connection between the electrical components operably coupled thereto.