Laser-based device utilizing multiple laser beams

• US 9,756,431 B2
• Filed: 01/17/2016
• Issued: 09/05/2017
• Est. Priority Date: 01/17/2016
• Status: Active Grant

• Current Assignee: Vocalzoom Systems Ltd.
• Original Assignee: Vocalzoom Systems Ltd.
• Inventors: Blumkin, Alexander, Ganani, Amir, Fishman, Tal, Bakish, Tal
• Primary Examiner(s): Payne, David
• Assistant Examiner(s): KRETZER, CASEY L
• Application Number:
  US14/997,533
• Publication Number:
  US 20170207856A1
• Time in Patent Office: 597 Days
• Field of Search: 398132-134, 381172
• CPC Class Codes: H04B 10/503 Laser transmitters
• CPC Class Codes: H04B 10/506 Multiwavelength transmitters
• CPC Class Codes: H04B 10/564 Power control
• CPC Class Codes: H04R 23/008 using optical signals for detecting or generating sound
• CPC Class Codes: H04R 23/02 Transducers using more than one principle simultaneously

Abstract

A laser-based device or sensor includes: a first laser transmitter having a first self-mix carrier frequency; a second laser transmitter having a second, different, self-mix carrier frequency; a first monitor photodiode to receive a first optical signal from the first laser transmitter, and to output a first electric signal; a second monitor photodiode to receive a first optical signal from the second laser transmitter, and to output a second electric signal; an electric connection to connect together the first electric signal and the second electric signal, forming a combined electric signal; a single laser receiver to receive the combined electric signal and to generate from it a spectrum that corresponds to both (i) optical feedback of the first laser transmitter, and (ii) optical feedback of the second laser transmitter. Alternatively, a single monitor photodiode is used, receiving optical signals from multiple laser transmitters, and outputting a single electric signal to a single laser receiver.

Claims

1. An apparatus comprising:

a first laser transmitter having a first self-mix carrier frequency;

a second laser transmitter having a second, different, self-mix carrier frequency;

a first monitor photodiode to receive a first optical signal from the first laser transmitter, and to output a first electric signal;

a second monitor photodiode to receive a first optical signal from the second laser transmitter, and to output a second electric signal;

an electric connection to connect together the first electric signal and the second electric signal, forming a combined electric signal;

a single laser receiver to receive the combined electric signal and to generate from it a spectrum that corresponds to both (i) optical feedback of the first laser transmitter, and (ii) optical feedback of the second laser transmitter;

a laser usefulness estimator to estimate self-mix usefulness of optical feedback received by the first laser transmitter;

a selective activation module (a) to selectively reduce a level of power provided to the first laser transmitter, while maintaining the first laser transmitter activated, and (b) to maintain a level of power provided to the second laser transmitter, if an estimated self-mix usefulness value of the first laser transmitter is below a pre-defined threshold value.

2. An apparatus comprising:

a first laser transmitter having a first self-mix carrier frequency;

a second laser transmitter having a second, different, self-mix carrier frequency;

a first monitor photodiode to receive a first optical signal from the first laser transmitter, and to output a first electric signal;

a second monitor photodiode to receive a first optical signal from the second laser transmitter, and to output a second electric signal;

an electric connection to connect together the first electric signal and the second electric signal, forming a combined electric signal;

a single laser receiver to receive the combined electric signal and to generate from it a spectrum that corresponds to both (i) optical feedback of the first laser transmitter, and (ii) optical feedback of the second laser transmitter;

a laser usefulness estimator (i) to estimate self-mix usefulness of optical feedback received by the first laser transmitter, and (ii) to estimate self-mix usefulness of optical feedback received by the second laser transmitter;

a selective activation module (a) to selectively reduce a level of power provided to the first laser transmitter, while maintaining the first laser transmitter activated, and (b) to maintain a level of power provided to the second laser transmitter, if an estimated self-mix usefulness value of the first laser transmitter is smaller by at least a pre-defined ratio from an estimated self-mix usefulness value of the second laser transmitter.