Planar laser illumination and imaging module (PLIIN) based semiconductor chips

• US 6,971,578 B2
• Filed: 02/05/2002
• Issued: 12/06/2005
• Est. Priority Date: 12/18/1995
• Status: Expired due to Fees

• Current Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Original Assignee: Metrologic Instruments Incorporated (Honeywell International Inc.)
• Inventors: Tsikos, Constantine J.
• Primary Examiner(s): Lee, Michael G.
• Assistant Examiner(s): Kim, Ahshik
• Application Number:
  US10/067,540
• Publication Number:
  US 20030042308A1
• Time in Patent Office: 1,400 Days
• Field of Search: 235/462.01, 235/462.14, 235/462.22, 235/462.24, 235/454, 235/462.11, 235/462.2, 235/462.31
• US Class Current: 235/462.14
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: G02B 26/106 having diffraction gratings as scanning elements, e.g. holographic scanners holographic optical elements G02B5/32, holography G03H
• CPC Class Codes: G02B 27/48 Laser speckle optics
• CPC Class Codes: G06K 17/0022 arrangements or provisious for transferring data to distant stations, e.g. from a sensing device "transfer between computer elements G06F13/00 "; data-transmission H04L
• CPC Class Codes: G06K 2207/1012 Special detection of object
• CPC Class Codes: G06K 2207/1013 Multi-focal
• CPC Class Codes: G06K 7/10 by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
• CPC Class Codes: G06K 7/10564 Light sources
• CPC Class Codes: G06K 7/10574 Multiple sources
• CPC Class Codes: G06K 7/10584 Source control
• CPC Class Codes: G06K 7/10594 Beam path
• CPC Class Codes: G06K 7/10603 Basic scanning using moving elements
• CPC Class Codes: G06K 7/10623 Constructional details
• CPC Class Codes: G06K 7/10633 by oscillation
• CPC Class Codes: G06K 7/10663 using hologram
• CPC Class Codes: G06K 7/10673 Parallel lines
• CPC Class Codes: G06K 7/10693 for omnidirectional scanning
• CPC Class Codes: G06K 7/10702 Particularities of propagating elements, e.g. lenses, mirrors G06K7/10831 takes precedence
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/10732 Light sources
• CPC Class Codes: G06K 7/10792 : Special measures in relation to the object to be scanned
• CPC Class Codes: G06K 7/10801 : Multidistance reading
• CPC Class Codes: G06K 7/10811 : Focalisation
• 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
• 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 7/10871 : randomly oriented data-fields, code-marks therefore, e.g. concentric circles-code
• CPC Class Codes: G06K 7/10881 : constructional details of hand-held scanners
• CPC Class Codes: G06K 7/10891 : the scanner to be worn on a finger or on a wrist
• CPC Class Codes: G06K 7/109 : adaptations to make the hand-held scanner useable as a fixed scanner
• CPC Class Codes: G06K 7/14 : using light without selection of wavelength, e.g. sensing reflected white light G06K7/10831 - G06K7/1097 take precedence
• CPC Class Codes: G07G 1/0054 : with control of supplementary check-parameters, e.g. weight or number of articles
• CPC Class Codes: H01L 21/28575 : on semiconductor bodies comprising AIIIBV compounds
• CPC Class Codes: H01L 29/452 : on AIII-BV compounds
• 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

Methods of and systems for illuminating objects using planar laser illumination beams having substantially-planar spatial distribution characteristics that extend through the field of view (FOV) of image formation and detection modules employed in such systems. Each planar laser illumination beam is produced from a planar laser illumination beam array (PLIA) comprising an plurality of planar laser illumination modules (PLIMs). Each PLIM comprises a visible laser diode (VLD, a focusing lens, and a cylindrical optical element arranged therewith. The individual planar laser illumination beam components produced from each PLIM are optically combined to produce a composite substantially planar laser illumination beam having substantially uniform power density characteristics over the entire spatial extend thereof and thus the working range of the system. Preferably, each planar laser illumination beam component is focused so that the minimum beam width thereof occurs at a point or plane which is the farthest or maximum object distance at which the system is designed to acquire images, thereby compensating for decreases in the power density of the incident planar laser illumination beam due to the fact that the width of the planar laser illumination beam increases in length for increasing object distances away from the imaging optics. Advanced high-resolution wavefront control methods and devices are disclosed for use with the PLIIM-based systems in order to reduce the power of speckle-noise patterns observed at the image detections thereof. By virtue of the present invention, it is now possible to use both VLDs and high-speed CCD-type image detectors in conveyor, hand-held and hold-under type imaging applications alike, enjoying the advantages and benefits that each such technology has to offer, while avoiding the shortcomings and drawbacks hitherto associated therewith.

Claims

1. A planar laser illumination and imaging module (PLIIM) realized on a semiconductor chip for integration into a system having a working range, said PLIIM comprising:

a pair of micro-sized diffractive or refractive cylindrical lens arrays mounted upon a pair of linear arrays of surface emitting lasers (SELs) for producing a plurality of substantially planar laser beam components,

said pair of linear arrays being fabricated on opposite sides of a linear electronic image detection array provided with optics having a field of view (FOV),

wherein said plurality of substantially planar laser beam components produce a composite substantially planar laser illumination beam that has substantially planar spatial distribution characteristics that extend through said field of view so that laser light reflected off an object illuminated by said composite substantially planar laser illumination beam is focused along said field of view and onto said linear electronic image detection array to form an image of said illuminated object; and

wherein said composite substantially planar laser illumination beam has substantially uniform power density characteristics over the spatial extent of said composite substantially planar laser illumination beam and thus over the working range of said system into which said PLIIM is integrated.

2. A PLIIM-based semiconductor chip for integration into a system having a working range, said PLIIM-based semiconductor chip comprising:

a pair of linear SEL arrays for producing a plurality of substantially planar laser illumination beam components;

a linear electronic image detection array having field of view (FOV) arranged in a coplanar relationship with said plurality of substantially planar laser illumination beam components,

wherein said linear electronic image detection array and said pair of linear SEL arrays are each formed on a common semiconductor substrate so that said linear electronic image detection array is arranged between said pair of linear SEL arrays; and

an integrated circuit package encasing said linear electronic image detection array and said pair of linear SEL arrays, said integrated circuit package having

electrical connector pins for connection to a host system,

first and second elongated light transmission windows disposed over said pair of linear SEL arrays, and

a third light transmission window disposed over said linear electronic image detection arrays;

wherein said plurality of substantially planar laser beam components are projected through said first and second elongated light transmission windows and produce a composite substantially planar illumination beam that has substantially planar spatial distribution characteristics that extend through said field of view projected through said third light transmission window, so that laser light reflected off an object illuminated by said composite substantially planar laser illumination beam is focused along said field of view and onto said image detection array to form an image of said illumination object; and

wherein said composite substantially planar laser illumination beam has substantially uniform power density characteristics over the spatial extent of said composite substantially planar laser illumination beam and thus over the working range of said system.

3. A micro-imaging device for integration into a system having a working range, said micro-imaging device comprising:

a PLIIM-based semiconductor chip mounted on a mechanically oscillating scanning element in order to sweep both the FOV of a linear image detection array and a coplanar planar laser illumination beam (PLIB) through a 3-D volume of space in which objects bearing bar code and other machine-readable indicia may pass;

wherein said PLIIM-based semiconductor chip includes a pair of micro-sized diffractive or refractive cylindrical lens arrays mounted upon a pair of linear arrays of surface emitting lasers (SELs) for producing a plurality of substantially planar laser beam components;

wherein said pair of linear arrays are fabricated on opposite sides of a linear electronic image detection array provided with optics having a field of view (FOV);

wherein said plurality of substantially planar laser beam components produce a composite substantially planar laser illumination beam that has substantially planar spatial distribution characteristics that extend through said field of view so that laser light reflected off an object illuminated by said composite substantially planar laser illumination beam is focused along said field of view and onto said linear electronic image detection array to form an image of said illuminated object; and

wherein said composite substantially planar laser illumination beam has substantially uniform power density characteristics over the spatial extent of said composite substantially planar laser illumination beam and thus over the working range of said system into which said micro-imaging device is integrated.

4. A PLIIM-based semiconductor chip comprising:

a plurality of linear SEL arrays which are electronically-activated to electro-optically illuminate the entire 3-D field of view (FOV) of an electronic image detection array without using mechanical scanning mechanisms;

wherein a plurality of micro-sized diffractive or refractive cylindrical lens arrays are mounted upon said plurality of linear SELs for producing a plurality of substantially planar laser beam components;

wherein said pair of linear SEL arrays are fabricated on opposite sides of said electronic image detection array provided with optics providing said 3-D FOV;

wherein said plurality of substantially planar laser beam components produce a composite substantially planar laser illumination beam that has substantially planar spatial distribution characteristics that extend through said 3-D FOV so that laser light reflected off an object illuminated by said composite substantially planar laser illumination beam is focused along said 3-D FOV and onto said image detection array to form an image of said illuminated object; and

wherein said composite substantially planar laser illumination beam has substantially uniform power density characteristics over the spatial of said composite substantially planar laser illumination beam and thus over the working range of said system into which said PLIIM-based semiconductor chip is integrated.

5. A PLIIM-based semiconductor chip for integration into a system having a working range, said PLIIM-based semiconductor chip comprising:

a miniature 2-D camera having a 2-D array of SEL diodes arranged about a centrally located 2-D area-type electronic image detection array having optics with a field of view (FOV), and said 2-D array of SEL diodes and 2-D area-type electronic image detection array are both mounted on a semiconductor substrate,

a micro-sized cylindrical lens arrays mounted upon said 2-D array of SEL diodes, for producing a plurality of substantially planar laser illumination beams;

an IC package for encapsulating said 2-D array of SEL diodes and said 2-D area-type electronic image detection array, and having

a centrally-located light transmission window positioned over said 2-D area-type electronic image detection array, and

a peripheral light transmission window positioned over said micro-sized cylindrical lens arrays and said 2-D array of SEL diodes;

wherein said plurality of substantially planar laser beam components are projected through said peripheral light transmission window and produce a composite substantially planar laser illumination beam that has substantially planar spatial distribution characteristics that extend through said field of view projected through said centrally-located light transmission window, so that laser light reflected off an object illuminated by said composite substantially planar laser illumination beam is focused along said field of view and onto said 2-D area-type electronic image detection array to form an image of said illuminated object; and

wherein said composite substantially planar laser illumination beam has substantially uniform power density characteristics over the spatial extent of said composite substantially planar laser illumination beam and thus over the working range of said system.

6. The PLIIM-based semiconductor chip of claim 5, wherein a light focusing lens element is aligned with and mounted over said centrally-located light transmission window to define a 3-D field of view (FOV) for forming images on said 2-D area-type electronic image detection array, whereas a 2-D array of cylindrical lens elements is aligned with and mounted over said peripheral light transmission window to substantially planarize laser emissions from linear SEL arrays comprising said 2-D array of SEL diodes during operation.

7. The PLIIM-based semiconductor chip of claim 6, wherein each cylindrical lens element is spatially aligned with a row or column is said 2-D area-type electronic image detection array, and each linear array of SELs in said 2-D array of SEL diodes, over which a cylindrical lens element is mounted, is electrically addressable (i.e. activatable) by laser diode control and drive circuits.

8. The PLIIM-based semiconductor chip of claim 7, wherein said laser diode control and drive circuits are fabricated on said semiconductor substrate.

9. The PLIIM-based semiconductor chip of claim 7, wherein said 2-D area-type electronic image detection array has a 3-D field of view (FOV), and said 2-D array of SEL diodes enables the illumination of an object residing within said 3D FOV during illumination operations, and the formation of an image strip on the corresponding rows (or columns) of detector elements in said 2-D area-type electronic image detection array.

10. A planar laser illumination and imaging module (PLIIM) realized on a semiconductor chip for integration into a system having a working range, said PLIIM-based semiconductor chip, said PLIIM comprising:

a linear electronic image detection array having image formation optics providing a field of view (FOV);

a pair of micro-sized cylindrical lens arrays mounted upon a pair of linear arrays of surface emitting lasers (SELs) fabricated on opposite sides of said linear electronic image detection array, so as to produce a plurality of substantially planar laser illumination beam (PLIB) components;

said linear electronic image detection array and said linear SEL arrays being formed a common semiconductor substrate, and encased within an integrated circuit (IC) package having electrical connector pins for establishing interconnections with a host system; and

first and second elongated light transmission windows disposed over said pair of linear arrays of SELs; and

a third light transmission window disposed over said linear electronic image detection array;

wherein said plurality of substantially planar laser beam components are projected through said first and second elongated light transmission windows and produce a composite substantially planar laser illumination beam that has substantially planar spatial distribution characteristics that extend through said field of view projected through said third light transmission window, so that laser light reflected off an object illuminated by said composite substantially planar laser illumination beam is focused along said field of view and onto said linear electronic image detection array to form an image of said illuminated object; and

wherein said composite substantially planar laser illumination beam has substantially uniform power density characteristics over the spatial extent of said composite substantially planar laser illumination beam and thus over the working range of said system.

11. The PLIIM-based chip of claim 10, wherein said micro-sized cylindrical lens arrays are fabricated from either diffractive or refractive optical material.

12. The PLIIM of claim 10, wherein said pair of linear arrays of SELs and said linear electronic image detection array are arranged in optical isolation of each other to avoid light leaking onto said linear electronic image array from within said IC package.

13. The PLIIM-based chip of claim 10, mounted on a mechanically oscillating scanning element in order to sweep both said FOV and coplanar composite substantially planar laser beam through a 3-D volume of space in which objects bearing bar code and/or other machine-readable indicis or graphical intelligence may pass.

14. A planar laser illumination and imaging module (PLIIM) for integration into a system having a working range, said PLIIM comprising:

a 2-D area-type electronic image detection array mounted on a common semiconductor substrate;

imaging optics with a field of view, mounted over said 2-D area-type electronic image detection array;

a 2-D array of surface emitting lasers (SELs) disposed about said 2-D area-type electronic image detection array; and

a 2-D array of cylindrical lens elements mounted over said 2-D array of SELs for producing a plurality of substantially planar laser beam components;

first and second elongated light transmission windows disposed over said 2-D array of cylindrical lens elements;

wherein said plurality of substantially planar laser beam components are projected through said first and second elongated light transmission windows and produce a composite substantially planar laser illumination beam that has substantially planar spatial distribution characteristics that extend through said field of view projected through a third light transmission window disposed over said 2-D area-type electronic image detection array, so that laser light reflected off an object illuminated by said composite substantially planar laser illumination beam is focused along said field of view and onto said image detecting array to form an image of said illuminated object; and

wherein said composite substantially planar laser illumination beam has substantially uniforms power density characteristics over the spatial extent of said composite substantially planar laser illumination beam and thus over the working range of said system.