Multimedia personal computer with active noise reduction and piezo speakers

• US 5,828,768 A
• Filed: 05/11/1994
• Issued: 10/27/1998
• Est. Priority Date: 05/11/1994
• Status: Expired due to Fees

• Current Assignee: New Transducers Limited (Alphabet Inc.)
• Original Assignee: Noise Cancellation Technologies, Inc. (NCT Group, Inc.)
• Inventors: Kokonaski, William, Hildebrand, Stephen F., Hiney, James W., McLoughlin, Michael P., Eatwell, Graham P.
• Primary Examiner(s): Isen, Forester W.
• Application Number:
  US08/241,440
• Time in Patent Office: 1,630 Days
• Field of Search: 348/729, 348/738, 348/552, 348/836, 381/71, 381/110, 381/24, 381/191, 381/190, 381/306, 381/333, 381/91, 381/122, 381/71.7
• US Class Current: 381/333
• CPC Class Codes: G06F 1/1616 with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position
• CPC Class Codes: G06F 1/1684 Constructional details or arrangements related to integrated I/O peripherals not covered by groups G06F1/1635 - G06F1/1675
• CPC Class Codes: G06F 1/1688 the I/O peripheral being integrated loudspeakers
• CPC Class Codes: G06F 3/162 Interface to dedicated audio devices, e.g. audio drivers, interface to CODECs
• CPC Class Codes: G10K 11/1785 Methods, e.g. algorithms; Devices G10K11/1781, G10K11/1783 take precedence
• CPC Class Codes: G10K 11/17853 of the filter
• CPC Class Codes: G10K 11/17857 Geometric disposition, e.g. placement of microphones
• CPC Class Codes: G10K 11/17861 using additional means for damping sound, e.g. using sound absorbing panels
• CPC Class Codes: G10K 11/17881 the reference signal being an acoustic signal, e.g. recorded with a microphone
• CPC Class Codes: G10K 2210/102 Two dimensional
• CPC Class Codes: G10K 2210/103 Three dimensional
• CPC Class Codes: G10K 2210/1053 Hi-fi, i.e. anything involving music, radios or loudspeakers
• CPC Class Codes: G10K 2210/1082 Microphones, e.g. systems using "virtual" microphones
• CPC Class Codes: G10K 2210/109 Compressors, e.g. fans
• CPC Class Codes: G10K 2210/11 Computers, i.e. ANC of the noise created by cooling fan, hard drive or the like
• CPC Class Codes: G10K 2210/112 Ducts vehicle exhausts G10K2210/12822
• CPC Class Codes: G10K 2210/3217 Collocated sensor and cancelling actuator, e.g. "virtual earth" designs
• CPC Class Codes: H04R 1/406 microphones
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 7/04 Plane diaphragms

Abstract

This invention involves the integration of piezoelectric speaker panels and microphones into a personal computer with a sound card to form a novel multi-media computer. In addition noise cancellation electronics and algorithms are also applied to enhance performance of the voice recognition system.

Claims

1. A laptop computer employing integrated piezoelectric panels and microphone in a novel arrangement, said computer comprising

a main housing means,

lid means physically and operatively connected to said main housing means, said lid means being configured as a hollow enclosure, display means on said lid means and adapted to provide a visual display,

piezoelectric panel means on said lid means and adapted in conjunction with said hollow enclosures, to provide an audio output, control means situated within said main housing means and adapted to drive said piezoelectric audio output and said visual display means in response to input signals,

input means adapted to provide inputs to said control means, wherein said input means includes a voice recognition means and microphone means adapted to function with said voice recognition means to produce input signals to said control means, and wherein said control means includes

analog to digital conversion means adapted to process said microphone means inputs,

finite impulse filter means adapted to receive the output from said conversion means,

summing means adapted to receive the output of said impulse means and adapted to produce a composite digital output,

automatic gain adjustment means adapted to process said composite digital output, and

multiplying digital to analog conversion means adapted to receive said processed output and to change the sensitivity of said microphone means.

2. A computer as in claim 1 wherein said input means includes at least one microphone means.

3. A computer as in claim 2 wherein said input means consists of an array of electret microphones and including variable gain amplification means to adjust their sensitivity.

4. A computer as in claim 3 and including a voice recognition means adapted to function with said microphone array to produce selected inputs to said control means.

5. A computer as in claim 4 and including active noise control means adapted to improve the performance of said voice recognition means and to create a zone of quiet adjacent said microphone array.

6. A computer as in claim 1 wherein said filter means and gain adjustment means reside on a single digital signal processing chip.

7. A computer as in claim 1 wherein said piezoelectric panel means comprise multiple piezoelectric elements mounted on said lid means adjacent said display means.

8. A computer as in claim 7 and including additional piezoelectric elements mounted in said main housing means.

9. A computer as in claim 1 and including additional piezoelectric panel means in said main housing means adapted to produce a second audio output which, in conjunction with said first audio output produces a stereophonic effect.

10. A computer as in claim 1 including multiple microphones mounted adjacent said display means on said lid means.

11. A computer as in claim 10 wherein said control means includes integrated circuit means with analog to digital and digital to analog converters, and

said microphone means comprising an array of microphones, said integrated circuit means adapted to control said microphones.

12. A computer as in claim 1 wherein said control means includes a computer sound card means, an audio amplifier and a step-up transformer means,

said computer sound card means adapted to produce an audio output which is fed into said audio amplifier and through said step-up transformer means to said piezoelectric means to cause said latter means to vibrate to produce said audio output.

13. A computer as in claim 1 wherein said microphone means comprises a micromachined microphone, said digital to analog conversion means adapted to change the bias voltage on said microphone to thereby control its sensitivity and consequently, the range and directivity thereof.

14. A computer as in claim 1 wherein said control means also includes active noise control means.

15. A computer as in claim 14 and including power supply means with a cooling fan means, said active noise control means adapted to attenuate noise generated by said fan means.

16. A computer as in claim 14 wherein said active noise control means is adapted to attenuate noise in the area of said microphone means so as to eliminate the effects of background noise in said voice recognition circuit means.

17. A computer as in claim 14 and including a disk drive means associated with said control means and adapted to produce audio signal inputs into said control means to drive said transducing means,

said active noise control means adapted to attenuate noise associated with said disk drive means.

18. A computer as in claim 14 wherein said active noise control means includes a digital signal processor means adapted to analyze the offending noise and generate a counter wave to cancel the offending noise.

19. A personal computer system having unique transducing means to thereby enhance audio inputs and outputs, said system including

(a) a three dimensional enclosure means with a display means thereon, said enclosure means having multiple planar surface wall means,

(b) a transducing means comprising a piezoelectric element means mounted on at least one of said planar surface means, said transducing means adapted to vibrate the enclosure means and said enclosure means adapted to act as a speaker in response to activation of said transducing means,

(c) control means adapted to receive inputs and convert them to visual display and audio outputs,

(d) input means adapted to produce inputs to said control means, wherein input means includes a voice recognition circuit means and microphone means adapted to function with said voice recognition circuit means to produce input signals to said control means;

wherein said control means includes

analog to digital conversion means adapted to process said microphone array inputs,

finite impulse filter means adapted to receive the output from said conversion means,

summing means adapted to receive the output of said impulse means and adapted to produce a composite digital output,

automatic gain adjustment means adapted to process said composite digital output, and

multiplying digital to analog conversion means adapted to receive said processed output and to change the sensitivity of said microphone means.

20. A system as in claim 19 wherein said microphone means comprises a micromachined microphone, said digital to analog conversion means adapted to change the bias voltage on said microphone to thereby control its sensitivity and consequently, the range and directivity thereof.

21. A system as in claim 19 wherein said filters and gain adjustments comprise a single digital signal processing chip.