A planar laser illumination and imaging (PLIIM) based device a linear image formation
and detection (IFD) module characterized by an F/# parameter mounted on a support
platform. The IFD module has a linear image detection array with vertically elongated
image detection elements and image formation optics having a field of view (FOV)
projected through the light transmission window into an illumination and imaging
field external to the hand-supportable housing and in which an object is presented
for illumination and imaging. Each vertically-elongated image detection element
having a height dimension (H) that is substantially greater than the width dimension
(W) thereof. A pair of planar laser illumination arrays (PLIAs) is mounted within
the hand-supportable housing and arranged on opposite sides of linear image formation
and detection module. Each PLIA includes a plurality of planar laser illumination
modules (PLIMs) for producing a plurality of spatially-incoherent planar laser
illumination beam (PLIB) components which are spatially aligned to produce a composite
planar laser illumination beam (PLIB) arranged in a coplanar relationship with
a portion of the FOV. Each PLIM includes a laser diode and beam focusing and diverging
optics for producing one PLIB component. For a given wavelength of planar laser
illumination, the height dimension (H) of each image detection element is selected
to provide the largest possible spatial averaging area, while the F/# parameter
of the linear IFD module is selected to provide the smallest possible average speckle
noise pattern size along the height dimension of vertically-elongated image detection
elements so that more individual speckle noise patterns can occur along the height
dimension of each vertically-elongated image detection element in the linear IFD
module. A series of linear images of object are sequentially detected by the linear
IFD module as the object moves past the hand-supportable housing, so that the series
of linear images can be grabbed and buffered for subsequent use in constructing
two-dimensional images of the object. The level of speckle noise power observed
at the linear image detection array is reduced through the spatial averaging of
individual speckle noise patterns occurring along the height dimension of the image
detection elements.