Abstract: A system and method for generating, enhancing, and detecting the amplitude and phase modulation of a laser under a condition of self-mixing is provided. The system may comprise a laser and a detector to extract the characteristic self-mix signal, which is then interpreted using algorithms implemented in hardware or software. In the case of the laser being a Vertical Cavity Surface Emitting laser (VCSEL), the output signal can be detected by monitoring the surface light emission by means of a beam splitter, or in some embodiments as emission from the bottom surface of the laser. In some embodiments, the system may further comprise a wavelength filter such as an etalon in the signal path.

Abstract: Laser-based devices utilizing temperature modulation for improved self-mix sensing. A self-mix laser unit includes: an active region having a first side and a second, opposite, side; a p-type Distributed Bragg Reflector (DBR) region, which is in direct touch with said first side of the active region; an n-type DBR region, which is in direct touch with the second side of the active region; and an n-type or p-type or other substrate. A heating unit provides modulated heating to the active region, either directly via an electrical resistor within the active region; or indirectly by passing or propagating modulated heat through one of the DBR regions or through the substrate. The modulated heating improves the laser-based self-mix signal.

Abstract: A system and method for generating, enhancing, and detecting the amplitude and phase modulation of a laser under a condition of self-mixing is provided. The system may comprise a laser and a detector to extract the characteristic self-mix signal, which is then interpreted using algorithms implemented in hardware or software. In the case of the laser being a Vertical Cavity Surface Emitting laser (VCSEL), the output signal can be detected by monitoring the surface light emission by means of a beam splitter, or in some embodiments as emission from the bottom surface of the laser. In some embodiments, the system may further comprise a wavelength filter such as an etalon in the signal path.

Abstract: A device has a laser unit, which includes: a top-side p-type DBR region; which is on top of and in direct touch with an active region; which is on top of and in direct touch with a bottom-side n-type Distributed Bragg Reflector (DBR) region; which is on top of a n-type substrate. The laser unit further includes a voltage measurement anode touching or being in proximity to a top surface of the active region; and a voltage measurement cathode touching or being in proximity to a bottom surface of the active region. The voltage between the voltage measurement anode and the voltage measurement cathode is directly measured; and is utilized for determining characteristics of a laser self-mix signal of the laser unit, without having or using a monitor photo-diode.

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) self-mix signal of the first laser transmitter, and (ii) self-mix signal of the second laser transmitter. Alternatively, a single monitor photodiode is used, receiving self-mix signals from multiple laser transmitters, and outputting a single electric signal to a single laser receiver.

Abstract: Device, system, and method of voice-based user authentication utilizing a challenge. A system includes a voice-based user-authentication unit, to authenticate a user based on a voice sample uttered by the user. A voice-related challenge generator operates to generate a voice-related challenge that induces the user to modify one or more vocal properties of the user. A reaction-to-challenge detector operates to detect a user-specific vocal modification in reaction to the voice-related challenge; by using a processor as well as an acoustic microphone, an optical microphone, or a hybrid acoustic-and-optical microphone. The voice-based user-authentication unit utilizes the user-specific vocal modification, that was detected as reaction to the voice-related challenge, as part of a user-authentication process.

Abstract: 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.

Abstract: A system and method for generating, enhancing, and detecting the amplitude and phase modulation of a laser under a condition of self-mixing is provided. The system may comprise a laser and a detector to extract the characteristic self-mix signal, which is then interpreted using algorithms implemented in hardware or software. In the case of the laser being a Vertical Cavity Surface Emitting laser (VCSEL), the output signal can be detected by monitoring the surface light emission by means of a beam splitter, or in some embodiments as emission from the bottom surface of the laser. In some embodiments, the system may further comprise a wavelength filter such as an etalon in the signal path.

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) self-mix signal of the first laser transmitter, and (ii) self-mix signal of the second laser transmitter. Alternatively, a single monitor photodiode is used, receiving self-mix signals from multiple laser transmitters, and outputting a single electric signal to a single laser receiver.

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) self-mix signal of the first laser transmitter, and (ii) self-mix signal of the second laser transmitter. Alternatively, a single monitor photodiode is used, receiving self-mix signals from multiple laser transmitters, and outputting a single electric signal to a single laser receiver.

Abstract: Optical microphone, laser-based microphone, and laser microphone having reduced-noise components of low-noise components. A laser microphone comprises a laser-diode associated with a low-noise laser driver TX; and a photo-diode associated with a low-noise photo-diode receiver RX. The low-noise laser driver TX supplies a drive current which is a combination of a Direct Current component having a first bandwidth, and an attenuated version of an Alternating Current component having a second, different, bandwidth. Additionally or alternatively, the low-noise photo-diode receiver RX utilizes hardware-based demodulation of the analog signal, and operates to remove a Direct Current component of its output signal prior to digitization.

Abstract: 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 face of a human speaker. The laser transmitter acts also as a self-mix interferometry unit that receives the optical feedback signal reflected from the face of the human speaker, and generates an optical self-mix signal by self-mixing interferometry of the laser power and the received optical feedback signal; and a speckles noise reducer to reduce speckles noise and to increase a bandwidth of the optical self-mix signal. The speckles noise reducer optionally includes a vibration unit or displacement unit, to cause vibrations or displacement of one or more mirrors or optics elements of the laser microphone, to thereby reduce speckles noise.

Abstract: Device, system, and method of user authentication utilizing an optical microphone or laser-based microphone. An optical microphone transmits an outgoing optical signal or laser beam towards a face of a human speaker; receives an incoming optical feedback that is reflected back from the face of the human speaker; performs self-mix interferometry that is based on the outgoing optical signal and the incoming reflected optical signal; and generates a user-specific feature or characteristic that uniquely characterizes said human speaker. A user authentication module operates to authenticate the user for performing a privileged or an access-controlled action, based on the user-specific characteristic that was generated, optionally in combination with one or more biometric features or authentication requirements.

Abstract: Device, system, and method of source separation, Blind Source Separation (BSS), signal processing, enhancement of acoustic signals, and reduction of noise from acoustic signals. A first acoustic microphone captures a first acoustic signal at a first location. A second acoustic microphone captures a second acoustic signal at a second location. An optical microphone or laser microphone, that targets or aims towards the first location and not towards the second location, captures an optical feedback signal. One or more correlator units, and one or more de-correlator units, perform particular correlation operations and de-correlation operations, among the first acoustic signal, the second acoustic signal, and the optical feedback signal; and produce, separately, a cleaned or reduced-noise version of the first acoustic signal, as well as a cleaned or reduced-noise version of the second acoustic signal.

Abstract: A device has a laser unit, which includes: a top-side p-type DBR region; which is on top of and in direct touch with an active region; which is on top of and in direct touch with a bottom-side n-type Distributed Bragg Reflector (DBR) region; which is on top of a n-type substrate. The laser unit further includes a voltage measurement anode touching or being in proximity to a top surface of the active region; and a voltage measurement cathode touching or being in proximity to a bottom surface of the active region. The voltage between the voltage measurement anode and the voltage measurement cathode is directly measured; and is utilized for determining characteristics of a laser self-mix signal of the laser unit, without having or using a monitor photo-diode.

Abstract: Laser-based devices utilizing temperature modulation for improved self-mix sensing. A self-mix laser unit includes: an active region having a first side and a second, opposite, side; a p-type Distributed Bragg Reflector (DBR) region, which is in direct touch with said first side of the active region; an n-type DBR region, which is in direct touch with the second side of the active region; and an n-type or p-type or other substrate. A heating unit provides modulated heating to the active region, either directly via an electrical resistor within the active region; or indirectly by passing or propagating modulated heat through one of the DBR regions or through the substrate. The modulated heating improves the laser-based self-mix signal.

Abstract: Lens, lens-holder, lens assembly, and packaging arrangement for a laser microphone or optical microphone. An optical lens is structured as a single, integrated, monolithic structure, having the optical lens therein, and having a top-region and a lower-region; and further having an external threading able to engage with internal threading of a lens-holder. Optionally, the entire monolithic structure of the lens-member, having the optical lens and its external threading, is formed of a single injection-molding plastic component. Optionally, expansion or shrinkage or curvature-modification of the optical lens, due to temperature modifications, causes the monolithic structure of the optical lens, and optionally also the lens-holder, to expand or shrink and to compensate for modification of focal length or other optical properties of the optical lens. Optionally, internal panels or surfaces of the monolithic structure of the optical lens, are conical or slanted inwardly.

Abstract: Optical microphone, laser-based microphone, and laser microphone having reduced-noise components of low-noise components. A laser microphone comprises a laser-diode associated with a low-noise laser driver TX; and a photo-diode associated with a low-noise photo-diode receiver RX. The low-noise laser driver TX supplies a drive current which is a combination of a Direct Current component having a first bandwidth, and an attenuated version of an Alternating Current component having a second, different, bandwidth. Additionally or alternatively, the low-noise photo-diode receiver RX utilizes hardware-based demodulation of the analog signal, and operates to remove a Direct Current component of its output signal prior to digitization.

Abstract: Device, system, and method of voice-based user authentication utilizing a challenge. A system includes a voice-based user-authentication unit, to authenticate a user based on a voice sample uttered by the user. A voice-related challenge generator operates to generate a voice-related challenge that induces the user to modify one or more vocal properties of the user. A reaction-to-challenge detector operates to detect a user-specific vocal modification in reaction to the voice-related challenge; by using a processor as well as an acoustic microphone, an optical microphone, or a hybrid acoustic-and-optical microphone. The voice-based user-authentication unit utilizes the user-specific vocal modification, that was detected as reaction to the voice-related challenge, as part of a user-authentication process.

Abstract: Devices, systems, and methods of enhanced automatic speech recognition. An acoustic microphone senses or captures acoustic signals that are uttered by a human speaker. An optical microphone or laser microphone transmits a laser beam aimed towards the face of the human speaker; receives a reflected optical feedback signal; and produces an optical self-mix signal by self-mixing interferometry. The self-mix signal is used by a training unit of a speech recognition processor. Optionally, the self-mix signal is used by an utterance recognition unit of the speech recognition processor. Optionally, the self-mix signal is utilized for enhancing the acoustic signals, or for constructing a digital filter that is applied to the acoustic signal; and the enhanced acoustic signal, or the filtered acoustic signal, is used by the training unit or by the a recognition unit of the speech recognition processor.