Self-mix utilizing laser multi-beam
A system includes a laser microphone or laser-based microphone or optical microphone. The laser microphone includes a laser transmitter to transmit an outgoing laser beam towards a human speaker. The laser transmitter acts also as a self-mix interferometry unit that receives the optical feedback signal reflected from the human speaker, and generates an optical self-mix signal by self-mixing interferometry of the laser beam and the received optical feedback signal. Instead of utilizing a single laser beam, multiple laser beams are used, by operating an array of laser transmitters, or by utilizing a laser beam splitter or a crystal to split laser beams or to diffract or scatter laser beams. Optionally, one or more laser beams may temporally scan a target area.
1. A system comprising:
a laser microphone comprising:
a self-mix interferometry unit, (i) to transmit via a laser transmitter at least one outgoing laser beam towards a human speaker, and (ii) to receive an optical feedback signal reflected from the human speaker, and (iii) to generate an optical self-mix signal by self-mixing interferometry of the at least one outgoing laser beam and the received optical feedback signal;
wherein said at least one outgoing laser beam comprises one of: (I) a single outgoing laser beam that temporally scans the face of the human speaker; (II) a set of multiple discrete outgoing laser beams;
an array of multiple laser transmitters, to concurrently transmit multiple laser beams towards the face of the human speaker;
wherein the self-mix interferometry unit is to receive and to selectively process a single particular reflected optical feedback signal out of multiple optical feedback signals that are reflected from said face of the human speaker,
wherein said particular reflected optical feedback signal is associated with a greater bandwidth of optical self-mixed signal, relative to other one or more optical feedback signals that are reflected from said face of the human speaker.
2. The system of claim 1 ,
wherein the self-mix interferometry unit is to receive and process multiple reflected optical feedback signals from said face of the human speaker.
3. The system of claim 1 ,
wherein the self-mix interferometry unit is to receive and process a combined feedback signal that corresponds to fusion of multiple reflected optical feedback signals from said face of the human speaker.
4. The system of claim 1 ,
wherein the self-mix interferometry unit is to autonomously lock-in on said particular reflected optical feedback signal out of multiple optical feedback signals that are reflected from said face of the human speaker.
5. A system comprising:
a laser microphone comprising:
a self-mix interferometry unit, (i) to transmit via a laser transmitter at least one outgoing laser beam towards a human speaker, and (ii) to receive an optical feedback signal reflected from the human speaker, and (iii) to generate an optical self-mix signal by self-mixing interferometry of the at least one outgoing laser beam and the received optical feedback signal;
wherein said at least one outgoing laser beam comprises one of: (I) a single outgoing laser beam that temporally scans the face of the human speaker; (II) a set of multiple discrete outgoing laser beams;
an array of multiple laser transmitters, to concurrently transmit multiple laser beams towards the face of the human speaker;
an optical feedback selector to select a single particular reflected optical feedback signal out of multiple optical feedback signals that are reflected from said face of the human speaker;
wherein the self-mix interferometry unit is to lock-in on, and to process, said particular reflected optical feedback signal.
6. The system of claim 1 ,
wherein said optical feedback selector is to select said single particular reflected optical feedback signal, out of multiple optical feedback signals that are reflected from said face of the human speaker, by comparing between bandwidths values of respective self-mix signals.
7. A system comprising:
a laser microphone comprising:
a self-mix interferometry unit, (i) to transmit via a laser transmitter at least one outgoing laser beam towards a human speaker, and (ii) to receive an optical feedback signal reflected from the human speaker, and (iii) to generate an optical self-mix signal by self-mixing interferometry of the at least one outgoing laser beam and the received optical feedback signal;
wherein said at least one outgoing laser beam comprises one of: (I) a single outgoing laser beam that temporally scans the face of the human speaker; (II) a set of multiple discrete outgoing laser beams;
an array of multiple laser transmitters, to concurrently transmit multiple laser beams towards the face of the human speaker;
an optical feedback fusion unit to fuse together multiple optical feedback signals that are reflected from said face of the human speaker, into a fused optical feedback signal;
wherein the self-mix interferometry unit is to lock-in on, and to process, said fused optical feedback signal.
8. The system of claim 1 ,
wherein the laser microphone comprises:
a self-mix signal quality estimator to estimate a quality of a self-mix signal associated with a particular outgoing laser beam;
a laser selective activation-and-deactivation unit, to selectively activate or deactivate a particular laser transmitter out of said array of multiple laser transmitter, based on the quality of self-mix signal associated with a particular outgoing laser beam.
9. The system of claim 1 ,
wherein the laser microphone comprises:
a laser generator to generate a single laser beam;
a laser-aiming unit comprising a motor, to temporally modify a spatial orientation of said laser transmitter.
10. The system of claim 1 ,
further comprising at least one acoustic microphone;
wherein the system is a hybrid acoustic-and-optical sensor.
11. The system of claim 7 ,
further comprising at least one acoustic microphone;
wherein the system is a hybrid acoustic-and-optical sensor which is comprised in a device selected from the group consisting of: a laptop computer, a smartphone, a tablet, a portable electronic device, a vehicular audio system.