1,249,498. Radar. ZELLWEGER Ltd. 12 Feb., 1969 [28 Feb., 1968], No. 7569/69. Heading H4D. A Doppler vehicle speeding radar has its horizontal beam 4, Fig. I, directed with the flow of traffic 3 at an angle a and is coupled to a camera positioned just above the beam and directed along an axis which although in the same vertical plane as the beam 4 may deviate in elevation from the horizontal. The camera is delayed from photographing a speeding vehicle 2 until it is within a " photozone " 5 parallel to beam 4. The view of the photozone 5, road edges 15, 16 vertical plane 12 of beam 4 and camera axis, and horizon 11 is as shown in Fig. 2. Since the photozone is not marked on the roadway and a lined plate fixed in front of the camera film and marked with the zone 5 would give the position of the zone varying with the inclination of the camera (Fig. 3), a template marked as Fig. 2 or with additional positioning lines 31, 32, 33, Fig. 5, is positioned on the developed photograph or superimposed on a screen projection thereof, using the centre plane line 12 and the horizon line 21 to line up with the photograph. The zone 5 then overlies the speeding vehicle. If the horizon is not visible in the photograph, line 21 can be lined up with distant objects in the photozone having the same height above ground as the camera, eg the top of the side door of a vehicle.
展开▼
