AUTOMATED OBJECT IDENTIFICATION AND ATTRIBUTE ACQUISITION SYSTEM HAVING A MULTI-COMPARTMENT HOUSING WITH OPTICALLY-ISOLATED LIGHT TRANSMISSION APERTURES FOR OPERATION OF A PLANAR LASER ILLUMINATION AND IMAGING (PLIIM) BASED LINEAR IMAGING SUBSYSTEM AND A LASER-BASE

• US 6,988,661 B2
• Filed: 05/16/2002
• Issued: 01/24/2006
• Est. Priority Date: 06/07/1999
• Status: Expired due to Fees

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Zhu, Xiaoxun, Knowles, C. Harry, Amundsen, Thomas, Naylor, Charles A., Schnee, Michael D., Tsikos, Constantine J., Dobbs, Russell Joseph
• Primary Examiner(s): LE, THIEN MINH
• Application Number:
  US10/150,491
• Publication Number:
  US 20030019933A1
• Time in Patent Office: 1,349 Days
• Field of Search: 23546201-46247, 235/472.01, 235/472.02, 235/472.03, 235/454, 235/455, 235/494, 235/383, 235/375
• US Class Current: 235/462.01
• CPC Class Codes: G02B 19/0014 at least one surface having optical power
• CPC Class Codes: G02B 19/0052 the light source comprising a laser diode coupling into light guides using intermediate optical elements G02B6/4204; semiconductor lasers having optical devices external to the laser cavity H01S5/005
• CPC Class Codes: G02B 19/0085 for use with both a detector and a source , e.g. in a transceiver, G02B19/009, G02B19/0095 take precedence
• CPC Class Codes: G02B 19/009 for use with infrared radiation
• CPC Class Codes: G02B 19/0095 for use with ultraviolet radiation
• CPC Class Codes: G02B 26/10 Scanning systems
• CPC Class Codes: G02B 27/095 Refractive optical elements
• CPC Class Codes: G02B 27/48 Laser speckle optics
• CPC Class Codes: G06K 7/10 by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
• CPC Class Codes: G06K 7/10594 Beam path
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/146 the method including quality enhancement steps
• CPC Class Codes: G06Q 10/00 Administration; Management
• CPC Class Codes: G06Q 30/00 Commerce
• CPC Class Codes: G06V 20/62 Text, e.g. of license plates, overlay texts or captions on TV images
• CPC Class Codes: G06V 30/144 using a slot moved over the image; using discrete sensing elements at predetermined points; using automatic curve following means
• CPC Class Codes: H01S 5/005 Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping H01S5/026, H01S5/18388 take precedence
• CPC Class Codes: H01S 5/02325 Mechanically integrated components on mount members or optical micro-benches
• CPC Class Codes: H01S 5/4025 Array arrangements, e.g. constituted by discrete laser diodes or laser bar H01S5/42 takes precedence

Abstract

An automated object identification and attribute acquisition system comprising a planar light illumination and imaging subsystem (PLIIM) based linear imaging subsystem, and a laser-based object profiling subsystem integrated within a multi-compartment system housing. The system housing has a substantially unitary construction and includes a first optically-isolated compartment formed in its upper deck portion for containing the PLIIM based linear imaging subsystem and associated components therewithin. The system housing also includes a second optically-isolated compartment formed in its lower deck portion, disposed below the first optically-isolated compartment; for containing the laser-based object profiling subsystem and associated components therewithin. First and second light transmission apertures are formed in the first optically-isolated compartment, for enabling the transmission of a planar laser illumination beam (PLIB) from the PLIIM based linear imaging sybsystem, and towards the object to be illuminated. A third light transmission aperture is formed in the first optically-isolated compartment, and spatially aligned with the first and second light transmission apertures, for enabling the field of view (FOV) of a linear image detection array provided in the PLIIM-based linear imaging subsystem, to project from the linear image detection array towards the illuminated object to be imaged. A fourth light transmission aperture is formed in the second optically-isolated compartment, and spatially distanced from the first optically-isolated compartment, for enabling the transmission of one or more laser scanning beams from the laser-based object profiling subsystem, towards the object being illuminated and imaged. By virtue of the present invention, it is now possible to automatically identify a moving object such as a package moving along a conveyor belt structure, and acquire geometrical and surface attributes thereof, using a single integrated device of substantially unitary construction, thereby simplifying system installation, set-up and maintenance in diverse field of operation

Claims

1. An automated object identification and attribute acquisition system comprising:

a planar light illumination and imaging (PLIIM) based linear imaging subsystem for automatically producing linear images of an object moving relative to said automated object identification and attribute acquisition system, so that said linear images can be buffered and used to construct a 2-D image of said object for subsequent processing and identification of said object;

a laser-based object profiling subsystem for laser scanning said object, acquiring information about the surface and/or geometrical attributes of said object, and producing information representative of said attributes; and

a system housing of substantially unitary construction having upper and lower deck portions, and including

a first optically-isolated compartment formed in the upper deck portion of said system housing for containing said PLIIM-based linear imaging subsystem and associated components therewithin, and

a second optically-isolated compartment formed in the lower deck portion of said system housing, disposed below said first optically-isolated compartment, for containing said laser-based object profiling subsystem and associated components therewithin;

first and second light transmission apertures formed in said first optically-isolated compartment, for enabling the transmission of a planar laser illumination beam (PLIB) from said PLIIM based linear imaging subsystem, and towards said object to be illuminated by said PLIB;

a third light transmission aperture formed in said first optically-isolated compartment, and spatially aligned with said first and second light transmission apertures, for enabling the transmission of a field of view (FOV) of a linear image detection array provided in said PLIIM-based linear imaging subsystem, to project from said linear image detection array towards said illuminated object to be imaged within said FOV which is coplanar with said PLIB; and

a fourth light transmission aperture formed in said second optically-isolated compartment, and spatially distanced from said first optically-isolated compartment, for enabling the transmission of one or more laser scanning beams from said laser-based object profiling subsystem, towards said object being illuminated and imagined, so as to profile the surface of said object.

2. The automated object identification and attribute acquisition system of claim 1, wherein said laser-based object profiling subsystem is a laser doppler imaging and profiling (LDIP) based subsystem capable of producing a pair of angularly spaced apart amplitude-modulated (AM) laser scanning beams for transmission through said fourth light transmission aperture, and measuring the profile characteristics of said laser scanned object as well as the velocity thereof.

3. The automated object identification and attribute acquisition system of claim 1, wherein said laser-based object profiling subsystem comprises a light source for illuminating the surface of the object with a structured light beam, and an electronic image detection array for detecting an image of said illuminated object.

4. The automated object identification and attribute acquisition system of claim 1, wherein said PLIIM-based linear imaging subsystem comprises:

a pair of planar laser illumination arrays (PLIAs) disposed in said system housing, each said planar laser array (PLIA) including a plurality of laser diodes arranged together in a linear manner and said PLIAs being arranged in relation to said linear image detection array, and for producing a pair of planar laser illumination beams (PLIBs), and projecting said pair of PLIBs through said first and second light transmission apertures and oriented such that the plane of said PLIBs is coplanar with said FOV of said linear image detection array so that the object can be simultaneously illuminated by said PLIBs and imaged within said FOV of said linear image detection array,

whereby a series of linear images of said object are sequentially detected by said linear image detection array as said object moves past first, second and third light transmission apertures, so that said series of linear images can be grabbed and buffered for subsequent use in constructing two-dimensional (2-D) images of said object.

5. The automated object identification and attribute acquisition system of claim 1, which further comprises:

an image frame grabber for grabbing linear images detected by said linear image detection array,

an image data buffer for buffering said grabbed linear images;

an image processing computer operably associated with said image data buffer, for processing said buffered linear images; and

a camera control computer for controlling said linear image formation and said detection module, and said pair of planar laser illumination arrays.

6. The automated object identification and attribute acquisition system of claim 1, wherein the FOV within said PLIIM-based linear linear imaging subsystem is provided by image forming optics having a fixed focal distance and a fixed focal length providing a fixed FOV.

7. The automated object identification and attribute acquisition system of claim 1, wherein the FOV within said PLIIM-based linear linear imaging subsystem is provided by image forming optics having a variable focal distance and a fixed focal length providing a fixed FOV.

8. The automated object identification and attribute acquisition system of claim 1, wherein the FOV within said PLIIM based linear imager is provided by image forming optics having a variable focal distance and a variable focal length providing a variable FOV.

9. The automated object identification and attribute acquisition system of claim 1, wherein said system housing is mounted over a conveyer-belt structure.

10. An automated object identification and attribute acquisition system comprising:

a planar light illumination and imaging (PLIIM) based linear imaging subsystem for automatically producing linear images of an object moving relative to said automated object identification and attribute acquisition system, so that said linear images can be buffered and used to construct a 2-D image of said object for subsequent processing and identification of said object;

a laser-based object profiling subsystem for laser scanning said object, acquiring information about the surface and/or geometrical attributes of said object, and producing information representative of said attributes; and

a system housing of substantially unitary construction having

a first optically-isolated compartment formed in the upper deck portion of said system housing for containing said PLIIM-based linear imaging subsystem and associated components therewithin, and

a second optically-isolated compartment formed in the lower deck portion of said system housing, disposed below said first optically-isolated compartment, for containing said laser-based object profiling subsystem and associated components therewithin;

first light transmission aperture formed in said first optically-isolated compartment, for enabling the transmission of a planar laser illumination beam (PLIB) from said PLIIM-based linear imaging subsystem, and towards said object to be illuminated by said PLIB;

a second light transmission aperture formed in said first optically-isolated compartment, and spatially aligned with said first light transmission aperture, for enabling the transmission of a field of view (FOV) of a linear image detection array provided in said PLIIM-based linear imaging subsystem, to project from said linear image detection array towards said illuminated object to be imaged within said FOV which is coplanar with said PLIB; and

a third light transmission aperture formed in said second optically-isolated compartment, and spatially distanced from said first optically-isolated compartment, for enabling the transmission of one or more laser scanning beams from said laser-based object profiling subsystem, towards said object being illuminated and imaged, so as to profile the surface of said object.

11. The automated object identification and attribute acquisition system of claim 10, wherein said laser-based object profiling subsystem is a laser doppler imaging and profiling (LDIP) based subsystem capable of producing a pair of angularly spaced apart amplitude-modulated (AM) laser scanning beams for transmission through said third light transmission aperture, and measuring the profile characteristics of said laser scanned object as well as the velocity thereof.

12. The automated object identification and attribute acquisition system of claim 10, wherein said laser-based object profiling subsystem comprises a light source for illuminating the surface of the object with a structured light beam, and an electronic image detection array for detecting an image of said illuminated object.

13. The automated object identification and attribute acquisition system of claim 10, wherein said PLIIM-based linear imaging subsystem comprises:

a planar laser illumination array (PLIA) disposed in said system housing, and including a plurality of laser diodes arranged together in a linear manner and said planar laser illumination arrays being arranged in relation to said linear image detection array, and for producing said planar laser illumination beam (PLIB), and projecting said PLIB through said first light transmission aperture and oriented such that the plane of said PLIB is coplanar with the field of view of said linear image detection array so that the object can be simultaneously illuminated by said PLIBs and imaged within said field of view of said linear image detection array,

whereby a series of linear images of said object are sequentially detected by said linear image detection array as said object moves past first, second and third light transmission apertures, so that said series of linear images can be grabbed and buffered for subsequent use in constructing two-dimensional (2-D) images of said object.

14. The automated object identification and attribute acquisition system of claim 10, which further comprises:

an image frame grabber for grabbing linear images detected by said linear image detection array,

an image data buffer for buffering said grabbed linear images;

an image processing computer operably associated with said image data buffer, for processing said buffered linear images; and

a camera control computer for controlling said linear image formation and said detection module, and said pair of PLIAs.

15. The automated object identification and attribute acquisition system of claim 10, wherein the FOV within said PLIIM-based linear imaging subsystem is provided by image forming optics having a fixed focal distance and a fixed focal length providing a fixed FOV.

16. The automated object identification and attribute acquisition system of claim 10, wherein the FOV within said PLIIM-based linear imaging subsystem is provided by image forming optics having a variable focal distance and a fixed focal length providing a fixed FOV.

17. The automated object identification and attribute acquisition system of claim 10, wherein the FOV within said PLIIM-based linear imaging subsystem is provided by image forming optics having a variable focal distance and a fixed focal length providing a fixed FOV.

18. The automated object identification and attribute acquisition system of claim 10, wherein said system housing is mounted over a conveyer-belt structure.