56 results about "Optical ring resonators" patented technology

A method and apparatus for performing refractive index, birefringence and optical activity measurements of a material such as a solid, liquid, gas or thin film is disclosed. The method and apparatus can also be used to measure the properties of a reflecting surface. The disclosed apparatus has an optical ring-resonator in the form of a fiber-loop resonator, or a race-track resonator, or any waveguide-ring or other structure with a closed optical path that constitutes a cavity. A sample is introduced into the optical path of the resonator such that the light in the resonator is transmitted through the sample and relative and / or absolute shifts of the resonance frequencies or changes of the characteristics of the transmission spectrum are observed. A change in the transfer characteristics of the resonant ring, such as a shift of the resonance frequency, is related to a sample's refractive index (refractive indices) and / or change thereof. In the case of birefringence measurements, rings that have modes with two (quasi)-orthogonal (linear or circular) polarization states are used to observe the relative shifts of the resonance frequencies. A reflecting surface may be introduced in a ring resonator. The reflecting surface can be raster-scanned for the purpose of height-profiling surface features. A surface plasmon resonance may be excited and phase changes of resonant light due to binding of analytes to the reflecting surface can be determined in the frequency domain.

The present invention is directed to hollow core optical ring resonators (HCORRs), methods of fabricating HCORRs, and methods of using HCORRs in sensing applications. In particular, the evanescent field and whispering gallery modes of the HCORRs may be used to detect a target analyte within the hollow core of the HCORR. Other features of the present invention include utilizing the HCORR as part of a multiplex sensing device, including using the HCORR in capillary electrophoresis and chromatography applications.

An optical resonant modulator includes an optical ring resonator and an optical loop that is coupled to the optical ring resonator by two couplers. The optical ring resonator can have a hybrid design in which the ring resonator is formed on an electro-optically passive material and the optical loop is formed on an electro-optically active material. An amplification section can be inserted between the electro-optically passive and the electro-optically active sections. In analog applications, an optical resonator includes a Mach Zehnder interferometer section having an input and an output, with a feedback path coupling the output to the input. Applications of the optical modulator of the invention, and a method for modulating an optical signal also are disclosed.

An optical waveguide device expands the operable frequency range toward the higher frequency side. The device includes a single-mode optical resonator waveguide serving as an optical ring resonator, a single-mode optical input / output waveguide located close to the resonator waveguide in an area, and a Mach-Zehnder interferometer formed in such a way as to include a part of the resonator waveguide as its first optical waveguide arm and a part of the input / output waveguide as its second optical waveguide arm in the area. The interferometer has a first optical coupler for optically coupling the first and second waveguide arms with an input-side part of the input / output waveguide and a remaining part of the resonator waveguide due to multiple-mode optical interference, and a second optical coupler for optically coupling the first and second waveguide arms with an output-side part of the input / output waveguide and the remaining part of the resonator waveguide due to multiple-mode optical interference.

A polymer waveguide resonator device for high-frequency ultrasound detection having a optical resonator coupled to a straight optical waveguide which serves as input and output ports. Acoustic waves irradiating the waveguide induce strain modifying the waveguide cross-section or other design property. As a consequence, the effective refractive index of optical waves propagating along the ring is modified. The sharp wavelength dependence of the high Q-factor resonator enhances the optical response to acoustic strain. High sensitivity is demonstrated experimentally in detecting broadband ultrasound pulses from a 10 MHz transducer.

A semiconductor laser comprises two optical ring resonators, each comprising an optical waveguide electrically pumped to provide optical gain. The two ring resonators have different round-trip optical path lengths, and are coupled to each other through a half-wave optical coupler. The half-wave optical coupler has a predetermined cross-coupling coefficient and a 180-degree cross-coupling phase. The cross-coupling coefficient is substantially less than the self-coupling coefficients in order to achieve an optimal single-mode selectivity of the laser. The first ring resonator has an optical path length such that its resonant wavelengths correspond to a set of discrete operating channels. The second ring resonator has a slightly different length so that only one resonant wavelength coincides with one of the resonant wavelengths of the first ring resonator over the operating spectral window. The lasing action occurs at the common resonant wavelength. In operation, at least a portion of the optical waveguide in each of the first and the second ring resonators are forward biased to provide substantially equal round-trip optical gains. The second ring resonator is tuned by varying the effective refractive index of a portion of the waveguide through an electrical means, resulting in wavelength switching among the set of discrete operating wavelengths as determined by the first ring resonator.

A method and apparatus for performing refractive index, birefringence and optical activity measurements of a material such as a solid, liquid, gas or thin film. The apparatus has an optical ring-resonator with a closed optical path that constitutes a cavity. A sample is introduced into the optical path of the resonator such that the light in the resonator is transmitted through the sample and relative and / or absolute shifts of the resonance frequencies or changes of the characteristics of the transmission spectrum are observed. A change in the transfer characteristics of the resonant ring, such as a shift of the resonance frequency, is related to a sample's refractive index (refractive indices) and / or change thereof. A reflecting surface may be introduced in a ring resonator. The reflecting surface can be raster-scanned for the purpose of height-profiling surface features.

A controllable optical ring resonator, a photonic system and a method of controlling an optical ring resonator employ control electrodes periodically spaced apart along a closed loop optical path of an optical waveguide. The controllable optical ring resonator includes the optical waveguide and a plurality of the periodically spaced control electrodes. The photonic system includes an input optical waveguide segment and the controllable optical ring resonator adjacent and optically coupled to the segment. The method includes providing the plurality of periodically spaced control electrodes, providing an optical signal within the optical path, and addressing one or more of the control electrodes to interact with the optical signal within the optical path.

Certain examples provide a transparent ultrasonic transducer including a transparent substrate and a transparent optical resonator positioned on the transparent substrate. The transparent optical resonator is to facilitate excitation of a biological sample and to receive acoustic emission from the biological sample triggered by the excitation, for example.Certain examples provide a ring resonator ultrasonic detector including a microscope cover slide. The microscope cover sheet includes a substrate and a ring optical resonator positioned on the substrate. The example ring optical resonator is to facilitate illumination of a biological sample and to receive acoustic emission from the biological sample in response to the illumination.

Disclosed are a near-field light source device as well as an optical head, an optical device, an exposure apparatus and a microscope device having such near-field light source device. As an example, the near-field light source device has a semiconductor laser having a ring-type optical resonator with a plurality of wave guides connected via mirror portions, a light blocking film formed in one of the mirror portions and having a small opening not greater than a wavelength size, and a diffraction grating formed on the light blocking film, wherein light oscillated from the semiconductor laser is diffracted by the diffraction grating, and the diffracted light is coupled to a rotation mode in the ring-type optical resonator.

An optical resonator, a photonic system and a method of optical resonance employ optical waveguide segments connected together with total internal reflection (TIR) mirrors to form a closed loop. The optical resonator includes the optical waveguide segments, the TIR mirrors and a photo-tunneling input / output (I / O) port. The photo-tunneling I / O port includes one of the TIR mirrors. The method includes propagating and reflecting an optical signal, or a portion thereof, in the optical resonator, and transmitting a portion of the optical signal through the photo-tunneling I / O port. The photonic system includes the optical resonator and a source of an optical signal.

An optical multiplexer / demultiplexer comprises one light guide main line which guides lights of a plurality of wavelengths, and two or more microring optical resonators directly optically coupled to the one light guide main line. The two or more microring optical resonators are arranged in any two of layers higher than, level with, and lower than a plane where the one light guide main line is disposed, and / or the two or more microring optical resonators are arranged on both sides of the one light guide main line in a light guide direction.

A laser-induced optical wiring apparatus is provided wherein optical wiring is realized by digital operations of a laser oscillator. The apparatus includes optical ring resonator formed of a loop-shaped optical waveguide on substrate. At least two optical gain sections are provided on the optical ring resonator. When each optical gain section is activated, a laser oscillator including the optical ring resonator and optical gain sections is enabled to oscillate. In this state, the gain of at least one of the optical gain sections is changed in accordance with an input signal, thereby changing the optical route gain of the optical ring resonator to change the oscillation state of the laser oscillator. A change in the laser oscillation state is detected by the optical gain section other than the at least one optical gain section, whereby an output signal is acquired.

A resonator fiber optic gyroscope (RFOG) is provided. The RFOG includes a gyroscope resonator having a clockwise input port and a counter-clockwise input port; a first laser configured to couple a clockwise optical beam into to the clockwise input port; a clockwise Pound-Drever-Hall modulation generator to modulate the clockwise optical beam with a resonance tracking modulation before the clockwise optical beam is coupled into the clockwise input port; bias correction electronics; FSR-detection-and-servo electronics including a switch communicatively coupled to the clockwise Pound-Drever-Hall modulation generator; a clockwise transmission detector configured to receive an optical beam output from the counter-clockwise input port and output signals to the bias correction electronics and the FSR-detection-and-servo electronics; and a second laser configured to couple a counter-clockwise optical beam into to the counter-clockwise input port, wherein the FSR of the gyroscope resonator is measured based on the Pound-Drever-Hall modulation of the clockwise optical beam.

The present invention relates to a laser capable of adjusting degree of polarization, which comprises of a semiconductor light amplifier connected drive power supply and a coupler, which are connected in serial with polarization controller used single mode fiber to form a bidirectional fiber optical ring resonator, the coupler is 2*2 broadband coupler whose two output interface are connected with two input port of a polarization beam combiner by optical fiber, polarization beam combiner outputs laser. The degree of polarization of laser can be remained above value of 0-100% to output common polarized laser or depolarization laser with low degree of polarization. The laser of present invention has simple structure, low cost, can resolve problems that the optical sensing, measuring and communication system depend on polarization.

An optical resonator, a photonic system and a method of optical resonance employ optical waveguide segments connected together with total internal reflection (TIR) mirrors to form a closed loop. The optical resonator includes the optical waveguide segments, the TIR mirrors and a photo-tunneling input / output (I / O) port. The photo-tunneling I / O port includes one of the TIR mirrors. The method includes propagating and reflecting an optical signal, or a portion thereof, in the optical resonator, and transmitting a portion of the optical signal through the photo-tunneling I / O port. The photonic system includes the optical resonator and a source of an optical signal.

A laser-induced optical wiring apparatus is provided wherein optical wiring is realized by digital operations of a laser oscillator. The apparatus includes optical ring resonator formed of a loop-shaped optical waveguide on substrate. At least two optical gain sections are provided on the optical ring resonator. When each optical gain section is activated, a laser oscillator including the optical ring resonator and optical gain sections is enabled to oscillate. In this state, the gain of at least one of the optical gain sections is changed in accordance with an input signal, thereby changing the optical route gain of the optical ring resonator to change the oscillation state of the laser oscillator. A change in the laser oscillation state is detected by the optical gain section other than the at least one optical gain section, whereby an output signal is acquired.

The invention relates to an optical comb repetition frequency doubling system based on an all-pass phase-lock optical ring resonator. The optical comb repetition frequency doubling system comprises an all-pass optical ring resonator and an electronic phase-lock unit, wherein the all-pass optical ring resonator consists of a single mode fiber optical direction coupler with adjustable coupling ratio and an automatically controlled optical delay line. In order to realize repetition frequency doubling, the resonator length is accurately controlled to be odd numbers of optical comb semi-resonator length by the electronic phase-lock unit. Energy loss is only related to the loss of the optical ring resonator, and thus the energy efficiency is high; the phase-lock unit is simple in configuration, obtained repetition frequency doubling is small in output pulse intensity, high in adjacent longitudinal mode compression ratio, good in frequency stability and low in phase noise; and moreover, a greater repetition frequency doubling number can be obtained by cascading a plurality of repetition frequency doubling units.

An optical ring-resonator converts visible wavelength radiation to ultraviolet wavelength radiation by frequency-doubling the visible wavelength radiation in an optically nonlinear crystal. The resonator includes an uncoated birefringent out-coupling prism. The visible wavelength radiation passes through faces of the prism at a Brewster-angle. Ultraviolet wavelength radiation enters the prism, is totally internally reflected, directed out of the prism at a Brewster-angle, and exits the ring-resonator as output radiation.

An optical resonator apparatus includes an optical resonator unit wherein ring optical resonators each including a first optical waveguide and a resonance wavelength adjustment electrode are coupled in cascade connection and round-trip lengths of the ring optical waveguides are different from each other and vary in order from an input side to an output side, and a controller that adjusts a resonance wavelength of each ring optical resonator in order beginning with the ring optical resonator provided at the most input side so as to match with an input light wavelength and, when an inter-channel occurs, adjusts the resonance wavelength of the first ring optical resonator from the input side so as to match with a second-matching input light wavelength and adjusts the resonance wavelengths of the second and succeeding ring optical resonators from the input side so as to match with the first-matching input light wavelength.

Certain examples provide a transparent ultrasonic transducer including a transparent substrate and a transparent optical resonator positioned on the transparent substrate. The transparent optical resonator is to facilitate excitation of a biological sample and to receive acoustic emission from the biological sample triggered by the excitation, for example.Certain examples provide a ring resonator ultrasonic detector including a microscope cover slide. The microscope cover sheet includes a substrate and a ring optical resonator positioned on the substrate. The example ring optical resonator is to facilitate illumination of a biological sample and to receive acoustic emission from the biological sample in response to the illumination.

The invention is entitled RF frequency synthesis based on offset optical frequency combs in ring resonators. The invention discloses an optical frequency comb generator device. In one implementation,the optical frequency comb generator device comprises a bus waveguide, at least a first optical ring resonator optically coupled to the bus waveguide, and at least a first grating located on the firstoptical ring resonator opposite from the bus waveguide. The first optical ring resonator and the first grating are configured to generate counter-propagating optical frequency combs that are offset from each other at a controllable bandwidth.