| 摘要 |
<p>The invention relates to an optical-electronic device of simple theroretical conception, allowing the direction and the speed to be detected of a running vehicle without direct external reference points, and which, although is placed completely isolated within its interior, yields data which can be also very precise, rapidly and continuously. It uses a ray of coherent laser light - produced on the spot - of low intensity, and used as a relative reference element, in combination with parallel reflecting planes. With a time measurement repeated in rapid sequence, by means of a clock with electronic data processor and by means of a photodetector, from the laser ray the computation elements necessary for determining the displacements due to the traveling speed and referred to outer reference elements previously extrapolated during the instrument calibration step are drawn. By being calibrated in compliance with the different cases, the device can measure both low and high speed values on any types of vehicles on to which it may be installed. The instrument is moved around its supporting point in a way very similar to the radar aerials, but as soon as the travelling direction has been identified, this movement is limited to short verification periods spaced over time.</p> |
