Recorders – Light or beam recording – Including record receiver or handling means therefor
Patent
1983-09-30
1985-04-02
Goldberg, E. A.
Recorders
Light or beam recording
Including record receiver or handling means therefor
352 5, 358112, 346 11, G01D 942
Patent
active
045090610
ABSTRACT:
Method and apparatus for forming a photographic record representing acoustic characteristics of a sound field such as the distribution of sound pressure and the distribution of equiphase surface wave are disclosed. A microphone and a light emitting diode are reciprocally moved to scan a plane in the sound field and an envelope signal of an output signal from the microphone is derived. The envelope signal is then sampled at a given sampling frequency to produce a sample signal. A carrier having a given frequency is amplitude-modulated with the sample signal to derive a modulated signal. Then, a switching circuit is controlled by the modulated signal in such a manner that when the envelope signal exceeds a predetermined value, the switching circuit is made on and off repeatedly and thus the light emitting diode is turned on and off at a rate of the carrier frequency to form a locas of the light spot. An image of the locus of the light spot is recorded optically on a photographic film.
REFERENCES:
patent: 1822057 (1931-09-01), Owens
patent: 3508015 (1970-04-01), Miller
Iida Kazuyoshi
Nomoto Sadao
Bridgestone Tire Company Limited
Goldberg E. A.
Reinhart M. J.
LandOfFree
Method and apparatus for forming photographic record of sound fi does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for forming photographic record of sound fi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for forming photographic record of sound fi will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1093392