HIGHLY ACCURATE DISTANCE MEASUREMENT DEVICE

摘要

Highly accurate electro-optical time of flight distance measuring device for determining a distance to a target. It is comprising at least a transmitter for sending out a pulse shaped optical radiation to the target, in particular as a pulse modulated laser beam from a laser diode, as well as a receiver for an optical signal, which signal is comprising parts of the optical radiation scattered back from the target, built for turning the optical signal to an electrical signal, in particular as a photodiode or avalanche photodiode, and a filter with a transfer-function for filtering the electrical signal, in particular an analog lowpass or bandpass filter whereby the filter is built in such a way that its transfer-function is of at least 4th order, in particular 5th or 7th or higher order, so that aliasing is suppressed. Further a waveform-sampler, as an analog-to-digital- converter, for digitalizing the pulse shape from the filtered electrical signal as time- and value-quantized digital data, and a computation means for a numerical evaluation of the distance according to the pulse shape or a pulse shape representing numerical signature from the digital data, in particular with a resolution in time being orders of magnitude better than the time-quantisation interval of the waveform sampler is comprised.