Adaptive angle and power adaptation in 3D-micro-mirror LIDAR

• US 8,446,571 B2
• Filed: 11/17/2009
• Issued: 05/21/2013
• Est. Priority Date: 12/29/2008
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Fiess, Reinhold, Steinkogler, Sascha
• Primary Examiner(s): RATCLIFFE, LUKE D
• Application Number:
  US12/620,426
• Publication Number:
  US 20100165323A1
• Time in Patent Office: 1,281 Days
• Field of Search: 356/4.01, 356/5.01, 701/301
• US Class Current: 356/5.01
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 7/4817 relating to scanning

Abstract

A device for recording a geometry of an environment of a device in a detection field with the aid of laser scanning may include a laser beam controlled by an oscillating micromechanical mirror. The detection field is specifiable in the vertical and horizontal directions by adapting an amplitude of oscillation of the micromechanical mirror. Driver-assistance systems are used for tasks both in the near field, such as a parking function, and in the distant field of the vehicle, such as a distance control or the detection of obstacles on the roadway. If the amplitude of the oscillation of the micro-mirror is then reduced in the horizontal direction and/or vertical direction, the spatial resolution for the reduced detection range is improved. Moreover, the higher intensity of the laser radiation impinging on the smaller detection region improves the signal-to-noise ratio of the detected signal.

Claims

1. A device for recording a three-dimensional image of an environment of a device in a detection field with the aid of laser scanning, comprising:

an oscillating micromechanical mirror that oscillates in a vertical direction and a horizontal direction;

a laser beam controlled by the oscillating micromechanical mirror; and

an arrangement via which to specify the detection field in the vertical direction and the horizontal direction by adapting, in both the vertical and the horizontal directions, at least one of an amplitude of oscillation of the micromechanical mirror and an oscillation frequency of the micromechanical mirror.

2. The device as recited in claim 1, wherein the device is configured such that a control signal is able to be applied to the micromechanical mirror at its resonance frequency and at a frequency that deviates from its resonance frequency.

3. The device as recited in claim 1, wherein the device is configured for varying a control signal applied to the micromechanical mirror.

4. The device as recited in claim 1, wherein the device is configured for selection of a radiation power of a laser that generates the laser beam, the selection of the radiation power occurring as a function of at least one of a frequency and an amplitude of a control signal of the micromechanical mirror.

14. The device as recited in claim 2, wherein the resonance frequency of the micromechanical mirror is fixed.

5. A method for recording a geometry of an environment in a detection field with the aid of laser scanning using a device including a laser beam controlled by an oscillating micromechanical mirror that oscillates in a vertical direction and a horizontal direction, the device determining three-dimensional information describing the environment from an intensity, specified by a receiver, of laser radiation backscattered or reflected from the environment, and the device determining a distance of objects in the environment from a propagation time of laser pulses, the method comprising:

specifying the detection field by an adaptation of an amplitude of oscillation of the micromechanical mirror in the vertical direction and the horizontal direction.

6. The method as recited in claim 5, wherein the detection field is adapted to a measuring task by specifying at least one of a frequency and an amplitude of a control signal of the micromechanical mirror.

7. The method as recited in claim 5, wherein the detection field is adapted according to at least one of a vehicle status data and a positional data.

8. The method as recited in claim 7, wherein the vehicle status data includes at least one of a velocity of a vehicle in which the device is integrated, a steering angle, a brake status, and a status of an electronic stability program (ESP).

9. The method as recited in claim 8, wherein the positional data includes map information.

10. The method as recited in claim 7, wherein the positional data includes map information.

11. The method as recited in claim 5, wherein a first detection field is used for detection of objects at a first distance, and a second detection field reduced from the first detection field is used for detection of objects at a second distance farther away than the first distance.

12. The method as recited in claim 5, wherein a first intensity of the laser radiation is used for detection of objects at a first distance, and a second intensity of the laser radiation increased from the first intensity is used for detection of objects at a second distance farther away than the first distance.

13. The method as recited in claim 11, wherein the first detection field and the second detection field are located in front of the vehicle, and the adaptation of the amplitude of oscillation of the micromechanical mirror causes the detection field to be switched between the first detection field and the second detection field.