Process and system for directional acoustic propagation

• US 20030035552A1
• Filed: 08/18/2002
• Published: 02/20/2003
• Est. Priority Date: 08/18/2001
• Status: Abandoned Application

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: Daimler AG (Mercedes-Benz Group AG)
• Inventors: Kolano, Guido, Linhard, Klaus
• Application Number:
  US10/223,159
• Publication Number:
  US 20030035552A1
• Time in Patent Office: Days
• US Class Current: 381/77
• CPC Class Codes: G10K 11/28 using reflection, e.g. parabolic reflectors
• CPC Class Codes: H04R 1/345 for loudspeakers
• CPC Class Codes: H04R 2217/03 Parametric transducers where sound is generated or captured by the acoustic demodulation of amplitude modulated ultrasonic waves

Abstract

A process and a device for producing a directed audio sound (3) on the basis of an amplitude demodulated ultrasound carrier signal (2) of high intensity. Therein, in accordance with the invention, the sound emitted by the ultrasound emitter (1) is reflected by a reflector (5) to a new direction. By appropriate shaping of the reflector surface, the audio sound (3) can be focused. The level of the ultrasound carrier signal (2) can be dampened by coating of the reflector (5) with an appropriate absorptive material, so that in the ideal case only the acoustic audio signal (3) reaches of the listener (4).

Claims

1. Process for directed sound irradiation of a listener (4) with audible acoustic audio signals (3) by modulation of the amplitude of an intense ultrasound carrier signal (2), which is emitted directionally from an ultrasound emitter (1), thereby characterized, that the audio sound (3) is directed to the listener (4) via a reflector (5), wherein the ultrasound carrier signal (2) prior to reaching the listener (4) is attenuated by a means introduced between ultrasound emitter (1) and listener (4).

2. Process according to claim 1, thereby characterized, that the reflector (5) is utilized as the means for damping.

3. Process according to claim 1 or 2, thereby characterized, that the dampening of the ultrasound carrier signal (2) occurs by absorption.

4. Process according to one of claims 1 through 3, thereby characterized, that the audio sound (3) is refocused by reflection.

5. Process according to one of claims 1 through 4, thereby characterized, that the main direction of emission of the reflected audio signal (3) can be changed by adjustment or pivoting of the reflector (5) and/or the ultrasound emitter (1).

6. Process according to one of claims 1 through 5, thereby characterized, that upon approaching or penetration by an object or a person in the area between ultrasound emitter (1) and reflector (5) the ultrasound carrier signal (2) is switched off or reduced in intensity.

7. Device for the directed sound irradiation of a listener (4) with acoustic recognizable audio signals (3), wherein an ultrasound emitter (1) emits with bundling an amplitude modulated ultrasound carrier signal (2) with high intensity, thereby characterized, that a reflector (5) is present, which reflects the audio sound (3) in the direction of the listener (4), and that between the ultrasound emitter (1) and listener (4) a means is introduced which strongly reduced the intensity of the ultrasound carrier signal (2) prior to reaching the listener (4).

8. Device according to claim 7, thereby characterized, that means for reducing the intensity of the ultrasound carrier signal (2) is a reflector (5).

9. Device according to claim 7 or 8, thereby characterized, that the surface of the reflector (5) exhibits a curvature, in such a manner, that the audio signal (3) is focused in the direction of the listener (4).

10. Device according to claim 9, thereby characterized, that the means reduce the intensity of the ultrasound carrier signal by absorption.

11. Device according to claim 10, thereby characterized, that the means are applied as layer upon the reflecting surface of the reflector (5).

12. Device according to claim 11, thereby characterized, that the layer is applied only to a part of the reflecting surface of the reflector (5).

13. Device according to claim 10, 11 or 12, thereby characterized, that the means is comprised of a fine porous material, for example, cloth.

14. Device according to one of claims 7 through 13, thereby characterized, that positioning or pivoting devices are provided, via which the ultrasound emitter (1) and/or the reflector (5) can be mechanically adjusted, so that the direction of the audio sound (3) is changeable.

15. Device according to one of claims 7 through 14, thereby characterized, that detectors are present, which detect the penetration of an object or person in the area between ultrasound emitter (1) and reflector (5) and produce a reduction in the intensity or as the case may be switching off of the ultrasound carrier signal (2).

16. Use of a device according to according to one of claims 7 through 15 for directed sound irradiation of occupants of a vehicle with audio sound.