The invention relates to a device with a detector element for receiving a light
beam reflecting on an object, wherein means for detecting the light beam are provided
in the detector element. The invention also relates to a method for distance measurement
using said receiver device. A device for determining the distance between a vehicle
and an obstacle or a vehicle driving ahead is already known as per DE 197 13 826
A1, wherein a pulsed laser beam serving as send signal scans line-by-line a two-dimensional
area using a self-rotating polygonal mirror, wherein said polygonal mirror has
a plurality of mirror surfaces that are bent at different angles. The pulse beam
reflecting on the object is focused on a detector element by optical lenses. Said
device known in prior art requires a polygonal mirror that is complicated to produce
and a complicated evaluation electronics due to the fact that, inter alia, the
scanning impulses for the control of the laser diode have to be synchronized with
the angular position of the polygonal mirror. The invention provides for a self-rotating
polygonal mirror with a plurality of mirror surfaces that are bent at a given angle
against the rotational axis of said polygonal mirror as receiver device so that
the reflecting light beam is deflected in said mirror surfaces by means of an optics
system and focused on the detector element.