Method of producing digital images of objects using planar laser illumination beams and electronic image detection arrays

1. A method of illuminating an object and forming a digital image thereof, comprising the steps of:

(a) providing an image formation and detection module having imaging optics with an optical axis and a field of view (FOV) focused onto an electronic image detecting array;

(b) producing a plurality of substantially planar laser beam components from a planar laser illumination array (PLIA) having a plurality of planar laser illumination modules (PLIMs), and allowing said plurality of substantially planar laser beam components to combine so as to produce a composite substantially planar laser illumination beam having substantially planar spatial distribution characteristics that extend through said field of view,

wherein each said PLIM includes a visible laser diode (VLD), a focusing lens, and a cylindrical optical element arranged therewith so as to produce one of said plurality of substantially planar laser illumination beam components, and wherein each said PLIM is adjustable relative to other said PLIMs so as to permit precise positioning of each said PLIM relative to the optical axis of the imaging optics of said image formation and detection module; and

(c) illuminating an object with said composite substantially planar laser illumination beam, while focusing laser light reflected off said illuminated object, along said field of view and onto said electronic image detecting array to form a digital linear (1D) image of said illuminated object.

2. The method of claim 1 , wherein during step (b) said plurality of substantially planar laser illumination beam components produced from said plurality of planar laser illumination modules are combined so that said composite substantially planar laser illumination beam has substantially uniform power density characteristics over the entire spatial extent of said composite substantially planar laser illumination beam over a working range.

3. The method of claim 2 , wherein during step (b) each said substantially planar laser illumination beam component is focused so that the minimum beam width thereof occurs at a point or plane which is the maximum object distance at which said image formation and detection module is designed to form and detect images, and thereby compensating for decreases in the power density of said composite substantially planar laser illumination beam caused by the fact that the width dimension of said composite substantially planar laser illumination beam increases in length for increasing object distances located away from said imaging optics.

4. The method of claim 1 , wherein said image formation and detection module and said planar laser illumination array are both contained in a system housing.

5. The method of claim 4 , wherein said system housing has a first light transmission aperture, a second light transmission aperture and a third light transmission aperture, and wherein said first light transmission aperture is optically isolated from said second and third light transmission apertures; and

wherein step (b) comprises projecting said field of view through said first light transmission aperture, while projecting components of said composite substantially planar laser illumination beam are projected through said second and third light transmission apertures.

6. The method of claim 4 , which comprises supporting said system housing above a conveyor belt structure along which said object is transported.

7. The method of claim 1 , wherein (c) further comprises forming a plurality of digital linear images of said object as said object is transported past said image formation and detection module, and wherein said plurality of digital linear images are automatically buffered and processed so as to produce a digital 2-D image of said object.