Measurement of standard visual range
AssigneeLicentia Patent-Verwaltungs-G.m.b.H.
InventorHerbert Sedlacek
Life of this patent
Estimating the term…
Abstract
For determining the standard visual range by determining the relation between a measured signal and a reference signal, the two signals are processed purely electronically by amplifying one of the signals in an amplifier having a digitally programmed amplification factor controlled by a digital value representing the computed range, forming a quotient between the output of the amplifier and the other of the signals, employing the resulting quotient value to adjust the amplifier amplification factor to a value representative of the standard visual range, and providing a digital output corresponding to the amplification factor.
Claims6
In apparatus for use in a system producing pulses of light and introducing the light into a scattering volume where the light is scattered, which apparatus serves to determine the standard visual range in an atmosphere corresponding to the scattering volume, and includes electro-optical measured signal producing means connected for monitoring the light scattered in the scattering volume and producing a measured signal representative of the amount of scattering, means for producing a reference signal, and comparator means having two inputs and an output, the improvement wherein said apparatus further comprises:
- means connecting one input of said comparator means to one of said signal producing means;
- variable-gain amplifier means connected between the other of said signal producing means and the other input of said comparator means for applying to said other comparator means input a signal whose value is a function of the signal produced by said other signal producing means and the gain of said amplifier means;
- gain adjusting means connected to said amplifier means and arranged to be controlled by digital signals for adjusting the gain of said amplifier means in response to such digital signals;
- digital counter means connected between the output of said comparator means and said gain adjusting means for performing a counting operation under control of the signal at the output of said comparator means and for supplying to said gain adjusting means signals representing its digital state and constituting the digital signals controlling said gain adjusting means;
- and
- indicator means connected to said counter means for providing a visible indication of the count state of said counter means.
Dependencies are inferred from the claim text.