Method and apparatus for optically scanning a scene
First Claim
1. An apparatus for optically scanning a scene comprising:
- an emitting part adapted to project an optical emitted beam onto the scene and to move the emitted beam relative to the scene; and
a receiving part adapted to receive and detect a reflected beam arising from a reflection of the emitted beam from the scene;
wherein said emitting part comprises;
an optical radiation source adapted to generate and emit the emitted beam;
a first prism element that is bounded by plural side surfaces, and that is rotatable about a first rotation axis, and that is positioned in a beam path of the emitted beam emitted by the optical radiation source so that the emitted beam penetrates into said first prism element and is deflected by an internal total reflection of the emitted beam from a respective one of said side surfaces of said first prism element dependent on a rotational position of said first prism element.
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Accused Products
Abstract
A light beam is deflected by refraction and total internal reflection through a first prism, and projected through a first lens onto a scene that is to be scanned. The prism rotates, which varies the deflection angle and scans the beam across the scene along a scan line. Preferably, the successive side surfaces of the prism have different tilt angles relative to the rotation axis, so as to respectively deflect the beam in different deflection planes which cause successive scan lines of the beam across the scene. The emitted beam gives rise to a reflected beam from the scene, which is received through a second lens and deflected onto a photodetector through a second prism congruent to and rotating synchronously with the first prism. This apparatus is suitable as a laser scanning device for an object recognition system or a spacing distance regulation system of a motor vehicle.
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Citations
24 Claims
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1. An apparatus for optically scanning a scene comprising:
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an emitting part adapted to project an optical emitted beam onto the scene and to move the emitted beam relative to the scene; and
a receiving part adapted to receive and detect a reflected beam arising from a reflection of the emitted beam from the scene;
wherein said emitting part comprises;
an optical radiation source adapted to generate and emit the emitted beam;
a first prism element that is bounded by plural side surfaces, and that is rotatable about a first rotation axis, and that is positioned in a beam path of the emitted beam emitted by the optical radiation source so that the emitted beam penetrates into said first prism element and is deflected by an internal total reflection of the emitted beam from a respective one of said side surfaces of said first prism element dependent on a rotational position of said first prism element. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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15. An apparatus for optically scanning a scene comprising:
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an emitting part adapted to project an optical emitted beam onto the scene and to move the emitted beam relative to the scene; and
a receiving part adapted to receive and detect a reflected beam arising from a reflection of the emitted beam from the scene;
wherein said emitting part comprises;
a first prism element that is rotatable about a first rotation axis, and that is bounded by plural side surfaces which are respectively tilted at different tilt angles relative to said first rotation axis; and
an optical radiation source adapted to generate the emitted beam and arranged to emit the emitted beam toward said first prism element so that the emitted beam penetrates into said first prism element and is deflected by an internal total reflection from a respective one of said side surfaces.
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16. A method of optically scanning a scene, comprising the steps:
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a) generating and emitting an emitted beam of light;
b) rotating a first prism element bounded by plural side surfaces about a first rotation axis; and
c) deflecting said emitted beam onto said scene using said first prism element, wherein said deflecting comprises penetrating said emitted beam into said first prism element and internally reflecting said emitted beam in said first prism element by a total reflection of said emitted beam from a respective one of said side surfaces;
wherein said rotating of said first prism element during said deflecting causes said emitted beam to be moved over said scene. - View Dependent Claims (17, 18, 19, 20, 21, 22, 23, 24)
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Specification