A cavity ring-down spectroscopy system and a method of modulating a light beam therein are provided. The cavity ring-down spectroscopy system includes at least one laser that generates a light beam, a first optical modulator positioned to attenuate the light beam from the at least one laser, a second optical modulator positioned to attenuate the light beam from the first optical modulator, a ring-down cavity positioned to receive the light beam from the second optical modulator, and at least one light sensor to detect an intensity of light leaked from the ring-down cavity.

There is provided a resonant cavity system. A first mirror is actuated at a first end of a resonant cavity to move in a direction between a first position relative to a second mirror at a second end of the resonant cavity, at which a cavity length between the first mirror and the second mirror is less than a resonance length for a laser beam, and a second position relative to the second mirror, at which the cavity length is greater than the resonance length. An event is triggered when the cavity length is proximal to the resonance length. The first mirror is continuously actuated to move in the direction between the first position and the second position during the event.

Disclosed herein is a method of determining a concentration of a subject based on fraction bound measurement. The method of determining a concentration of a subject based on fraction bound measurement may include fixing a ligand to a surface of an optical device, measuring a fraction bound of a subject to be detected based on an optical signal when the subject reacts to the ligand fixed to the surface of the optical device, and determining a relative value of a concentration of the subject based on a ratio of measured values of the fraction bounds of the subject and a reference signal.

The present invention relates to an optoelectronic device (1) for detection of a target substance dispersed in a fluid (50). The optoelectronic device comprises:a light source (2) adapted to emit a light radiation (L.sub.E) having an adjustable wavelength .sub.S;an integrated electronic circuit (100) comprising a photonic circuit (10) operatively coupled to said light source;a control unit (9) operatively coupled to said light source and to said photonic circuit.

There is provided a method of tuning a resonant cavity and a cavity ring-down spectroscopy system using the same. A first mirror is actuated at a first end of a resonant cavity to move in a direction between a first position relative to a second mirror at a second end of the resonant cavity, at which a cavity length between the first mirror and the second mirror is less than a resonance length for a laser beam, and a second position relative to the second mirror, at which the cavity length is greater than the resonance length. An event is triggered when the cavity length is proximal to the resonance length. The first mirror is continuously actuated in the direction between the first position and the second position during the event.

A method to measure the refractive index of a sample, includes: providing a plasmonic sensor including a sensing surface in contact with the sample; providing an optical resonator, the plasmonic sensor being integrated therein as a reflecting surface; providing a first input field of electromagnetic radiation as a primary carrier; providing a second input field of electromagnetic radiation as a secondary carrier having a second frequency different from the first and defined as:

second frequency=first frequency+v and having a TE and/or a TM polarized component; impinging simultaneously with the first and second input field the plasmonic sensor; tuning the frequency of the first field and/or the value of v; detecting a resonator output power corresponding to the first and second intra-cavity fields resonating; determining a difference between the first and the second resonating frequencies; and calculating the refractive index of the sample from the difference.

A spectroscopy system is disclosed, and includes a resonant cavity, a first conduit configured to couple at a first end thereof to a gas source, and at a second end thereof to a first end of a sorbent tube containing a sample for analysis, and a second conduit configured to couple at a first end thereof to a second end of the sorbent tube, and at a second end thereof to the resonant cavity.

A cavity ring-down spectroscopy system and a method of modulating a light beam therein are provided. The cavity ring-down spectroscopy system includes at least one laser that generates a light beam, a first optical modulator positioned to attenuate the light beam from the at least one laser, a second optical modulator positioned to attenuate the light beam from the first optical modulator, a ring-down cavity positioned to receive the light beam from the second optical modulator, and at least one light sensor to detect an intensity of light leaked from the ring-down cavity.

There is provided a method of tuning a resonant cavity and a cavity ring-down spectroscopy system using the same. A first mirror is actuated at a first end of a resonant cavity to move in a direction between a first position relative to a second mirror at a second end of the resonant cavity, at which a cavity length between the first mirror and the second mirror is less than a resonance length for a laser beam, and a second position relative to the second mirror, at which the cavity length is greater than the resonance length. An event is triggered when the cavity length is proximal to the resonance length. The first mirror is continuously actuated in the direction between the first position and the second position during the event.

Methods and systems for analyzing a sample and generating a predictive model using cavity ring-down spectroscopy are disclosed. At least part of a sample is loaded in a ring-down cavity. For each of a set of wavelengths, a laser beam is generated and directed into the ring-down cavity. The laser beam entering the ring-down cavity is extinguished. Light intensity decay data for light exiting the ring-down cavity is registered via a light intensity sensor system. A probability is determined from the light intensity decay data for the set of wavelengths that a subject from which the sample was received has a physiological condition or a degree of the physiological condition at least indirectly using a dataset of light intensity decay data for previously analyzed samples for which the presence or the absence of the physiological condition or the degree of the physiological condition have been identified.