PURPOSE: To provide a speed measuring apparatus of a space filter type which can obtain correct measuring results in spite of its compact and low-cost structure, and a speed controlling system and an automobile equipped with the measuring apparatus.
CONSTITUTION: A speed measuring device 1 is set to a shaft 3 which shows little change in the distance to a road surface 4 while a vehicle 2 is running, so that the distance between the device 1 and the road surface 4 is maintained to be approximately constant. In consequence, a light shielding plate with a small hole formed on the focal plane of a photodetecting lens is eliminated in the device 1, the reflected light from the road surface 4 can be efficiently utilized and a light source part of the device 1 can be made smaller.
| JP2021121510 | WHEEL |
| JP3365799 | [Title of Invention] Distance / Velocity Measuring Device |
| JPH03111762 | SPECKLE SPEED SENSOR |
UNO TETSUYA
TAKAGI JUNICHI
