Device and method for sensing an object or a person in the interior of a vehicle

• US 6,437,461 B1
• Filed: 02/25/2000
• Issued: 08/20/2002
• Est. Priority Date: 02/25/1999
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Roth, Christoph, Roesl, Reinhard, Mader, Gerhard, Stierle, Thomas, Hamperl, Reinhard, Waldmann, Alexander
• Primary Examiner(s): Huynh, Kim
• Assistant Examiner(s): DeBeradinis, Robert L.
• Application Number:
  US09/513,624
• Time in Patent Office: 907 Days
• Field of Search: 347/242, 372/38.02, 369/54, 307/12.1, 307/9.1, 701/45
• US Class Current: 307/10.1
• CPC Class Codes: B60R 21/01552 detecting position of specific human body parts, e.g. face, eyes or hands
• CPC Class Codes: G01S 17/04 Systems determining the presence of a target
• CPC Class Codes: G01S 7/4802 using analysis of echo signal for target characterisation; Target signature; Target cross-section

Abstract

In order to sense an object or a person in the interior of a vehicle, laser pulses are output by a laser. Sensing devices are provided for sensing a characteristic variable that is decisive for the transmission energy of the laser. The transmission energy is reduced or the emission of a laser pulse is prevented as a function of the sensed characteristic variable.

Claims

1. A device for sensing an object in an interior of a vehicle, comprising:

a laser outputting a laser pulse into the interior of the vehicle;

a sensing device for sensing a characteristic variable of a transmission energy of said laser; and

a control device for reducing the transmission energy and for preventing said laser pulse from being emitted in dependence on the characteristic variable sensed by said sensing device.

2. The device according to claim 1, wherein said sensing device senses a characteristic variable of the laser pulse.

3. The device according to claim 2, wherein said sensing device senses the characteristic variable on a basis of a plurality of output laser pulses.

4. The device according to claim 3, wherein said control device reduces the transmission energy and prevents the laser pulse from being emitted in an event that both the characteristic variable determined on the basis of the plurality of laser pulses and the characteristic variable determined on a basis of said laser pulse each exceed respectively assigned limiting values.

5. The device according to claim 1, wherein said sensing device senses a characteristic variable of an electrical operating energy of said laser.

6. The device according to claim 1, wherein said sensing device senses a characteristic variable of irradiated energy of said laser.

7. The device according to claim 6, wherein said sensing device contains an optical receiver for sensing said laser pulse.

8. The device according to claim 1, wherein said control device has a comparator for comparing a picked-up energy with a limiting value.

9. The device according to claim 8, including a power supply supplying power to said laser, and said control device disconnects said laser from said power supply if the limiting value is exceeded.

10. The device according to claim 1, including a control and evaluation unit for controlling said laser and for evaluating laser pulses reflected by the object, and said control device and said control unit and evaluation unit are spatially separate from one another.

11. A method for sensing an object in an interior of a vehicle, which comprises:

outputting a laser pulse into the interior of the vehicle via a laser;

sensing a characteristic variable controlling a transmission energy of the laser resulting in a sensed characteristic variable; and

performing one of reducing the transmission energy of the laser and preventing an emission of the laser pulse in dependence on the sensed characteristic variable.