摘要 |
A device (100) for measuring a distance (h) from a reflecting surface (101), such as a surface of a glass, comprises two light sources (102, 103) for emitting light beams to incident into a reflection position/area (106), which is common for the both beams on the reflecting surface. The device also comprises a detector (104, 105) for determining the individual positions (d1, d2) of the light beams reflected from the reflecting surface (101) onto the detector surface (104, 105). The (h) distance from the reflecting surface is then determined based on the positions (d1, d2) of the two light beams at the detector surface by numerically solving a trigonometric function. |