Device for distance measurement
First Claim
1. An apparatus (1) with a detector element (9) for receiving a light beam (3a, 3b) reflected by an object, whereby means (7, 5) are provided for deflecting the reflected light beam (3b) onto said detector element (9), characterized in that a rotating polygonal mirror (5) is provided as a means for deflecting the reflected light beam (3b), said polygonal mirror having a plurality of mirror surfaces (5a, 5b, 5c) inclined at an angle (β
- ) to the rotation axis (6) of the rotating polygonal mirror (5), whereby the detector element (9) is arranged in the direction of the rotation axis (6) of the polygonal mirror (5), and that an optic (7) is allocated to each mirror surface (5a, 5b, 5c) of the polygonal mirror (5) for focusing the reflected light beam (3b) onto the detector element (9), said optic rotating in synchronism with the polygonal mirror (5).
1 Assignment
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Accused Products
Abstract
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.
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Citations
12 Claims
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1. An apparatus (1) with a detector element (9) for receiving a light beam (3a, 3b) reflected by an object, whereby means (7, 5) are provided for deflecting the reflected light beam (3b) onto said detector element (9), characterized in that a rotating polygonal mirror (5) is provided as a means for deflecting the reflected light beam (3b), said polygonal mirror having a plurality of mirror surfaces (5a, 5b, 5c) inclined at an angle (β
- ) to the rotation axis (6) of the rotating polygonal mirror (5), whereby the detector element (9) is arranged in the direction of the rotation axis (6) of the polygonal mirror (5), and that an optic (7) is allocated to each mirror surface (5a, 5b, 5c) of the polygonal mirror (5) for focusing the reflected light beam (3b) onto the detector element (9), said optic rotating in synchronism with the polygonal mirror (5).
- View Dependent Claims (2, 8, 9, 10, 11, 12)
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3. claims 3 to 7 (canceled).
Specification