A laser scanner apparatus is disclosed herein for measuring the geometry
and physical dimensions of one or more objects in a specified location or
platform. The specified location or platform is within a range less than
a predetermined maximum object distance. The laser scanner includes a
waveform generator that generates a predetermined reference waveform to
an analog laser that provides an modulated laser beam responsive to the
reference waveform, an optical scanning system which 1) transmits and
scans the object with the modulated laser light beam and 2) includes a
means for receiving reflected the modulated laser light from the surface
of an object on the platform or specified location, an avalanche
photo-detector positioned to receive the processed modulated light from
the optical processing system, and convert energy in the incident light
into an amplitude-modulated range signal, a mixer is provided to
down-convert the frequency of the range signal into a lower (LF)
frequency. In practice, a first electrical circuit receives the
down-converted range signal and converts it into a converted waveform
that has a sinusoidal wave falling and rising that correspond to the zero
crossings. The reference waveform is also applied to a mixer that
down-converts it to the LF frequency. A second electrical circuit
receives the down-converted reference waveform and converts it a second
converted waveform that has a sinusoidal wave falling and rising that
correspond to the zero crossings. A computer receives the first and
second converted waveforms and outputs a highly accurate signal
indicative of the time delay there between. The time delay is used by the
computer system to determine the physical dimension of the particular
scanning.