Download THRESHOLD I:

5,880,821
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number of said return pulses coincide Within a speci?ed
precision, at Which time an average of said predeter
mined number of said return pulses are utiliZed in said
17. A laser range ?nder apparatus for determining a range
to a target based upon a ?ight time of a pulse toward said
target, said apparatus comprising:
a laser transmit section for generating a number of laser
pulses for transmission to a target;
a laser receive section for receiving re?ected laser pulses
from said target;
a precision timing section coupled to said laser transmit
section and said laser receive section for determining a
?ight time of said laser pulses to said target and said
re?ected laser pulses from said target;
a central processor section coupled to said precision
timing section for determining a range to said target
derived from said ?ight time of said laser pulses and
said ?ight time of said re?ected laser pulses; and
a user selectable target acquisition mode sWitch coupled
to said processor for selecting betWeen at least a high
sensitivity mode and a loW sensitivity receiver mode of
operation Wherein said central processor places
detected return pulses in a stack until a predetermined
central processor section to determine said range to said
target.
18. The laser range ?nding apparatus according to claim
17 Wherein said computing section determines a ?rst preci
sion for a ?rst set of said transmitted and pulses and a second
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precision for a second set of said pulses.
19. The range ?nder according to claim 18 Wherein said
central processor section includes means for holding passage
of range signals to said stack if the range signals are shorter
than a predetermined range value.
20. The range ?nder according to claim 18 Wherein said
precision timing circuit receives a hold off signal from said
central processor for preventing processing of a received
pulse prior to passage of a predetermined time folloWing
transmission of each of said transmitted pulses.