Optical distance measurement device

摘要

Optical range finders are configured to transmit optical bursts toward a target and detect a corresponding received burst. DC offset in the received burst due to square law detection can be offset based on a difference between high pass and low pass filtered portions of the received burst. Edge records associated with bursts can be obtained, and correlated with a reference signal or waveform to obtain a range estimate.

主权项

1. A range finding device, comprising a receiver that includes:
a detector configured to convert a received optical signal from an object into an analog signal; an analog filter configured to apply a dc offset associated with the received analog signal over the duration of a received signal burst; a zero-crossing detector configured to convert the received signal into binary logic states at successive sample points; a correlator configured to compare a stored transmit code sequence with one or more stored edge detected signal records to produce a derivative of a delayed correlation function; and a delay estimator configured to estimate a delay based on a zero-crossing point of the delayed correlation function.