A digital measuring device implemented on a photonic integrated circuit, the digital measuring device including a laser source configured to provide light, a first ring resonator configured to produce a first frequency comb of light from the laser source, wherein at least a portion of the first frequency comb of light is directed at a moving object, a local oscillator configured to provide a reference beam, at least one waveguide structure configured to combine the reference beam with light reflected from the moving object to produce a measurement beam, a first multiplexer configured to split the measurement beam into a plurality of channels spaced in frequency, and a plurality of detectors configured to detect an intensity value of each channel of the plurality of channels to measure a distance between the digital measuring device and the moving object.

A method and a system for interrogating an optical fiber includes a probe signal that has a first frequency comb at a first repetition rate (Δf) injected into the optical fiber. A backscattering signal that includes the probe signal convolved with an impulse response of the optical fiber in reflection which is sensitive to at least one parameter being measured from the optical fiber is gathered. The backscattering signal is beaten with a local oscillator signal to generate a beating signal, the local oscillator signal including a second frequency comb at a second repetition rate that is offset from the first repetition rate (Δf+δf) and being mutually coherent with the first frequency comb. The resulting beating signal is analysed to thereby determine the at least one parameter being measured from the optical fiber.

Systems and methods for measuring displacements at the picometer level are provided. A system can include a Michelson interferometer having a fixed arm and a measurement arm. As the length of the measurement arm changes, the output supplied to the interferometer from a variable wavelength light source is changed until the intensity of the resulting inference pattern is maximized. The wavelength of the light at the point the interference pattern is maximized is then measured by mixing light from the light source with the output from a frequency comb generator. The resulting frequency measurement is then converted to a length measurement.

A device that uses two intensity modulated frequency combs to measure distances with high precision and high data acquisition rate without any moving parts and without length ambiguity that is inherent conventional ranging based on two frequency combs. A modulation signal having a repetition rate identical to the repetition rate difference between the two combs is used to do a direct time-of-flight length measurement, hence avoiding the given length ambiguity while harvesting the increased precision of the dual-comb approach.

An opto-electronic dual-comb interferometric distance measuring method and device wherein a signal comb is chromatically divided into a target signal comb and a non-target signal comb at a emission position, preferably by an optical interleaver in a measurement probe of the device. Only the target signal comb serves as a free beam emitted to the target. The non-target signal comb serves for generation of additional or compensation internal phase differences. Thus, the distance to the target is based on first, target related phase differences and on the second, internal compensation phase differences.

Disclosed are methods and an assembly for robust one-shot interferometry, in particular for optical coherence tomography according to the spatial domain approach (SD-OCT) and/or according to the light-field approach. In one embodiment, the method and the assembly may be used for measurements on material and living tissue, for distance measurement, for 2D or 3D measurement with a finely structured light source imaged onto the object in a diffraction-limited way, or with spots thereof. The assembly may comprise an interferometer having object and reference arms and a detector for electromagnetic radiation. In other embodiments, during a detection process, a plurality of spatial interferograms may be formed by making an inclined and/or curved reference wavefront interfere with an object wavefront for each measurement point. The resulting spatial interferograms may be detected in a single detector frame and may be further evaluated via a computer program.

Systems and methods for soliton microcomb-based precision dimensional metrology via spectrally-resolved interferometry are described. In an embodiment, the system includes a dual-pumped soliton microcomb generator comprising a pump, a microresonator, and an auxiliary pump and that generates a single-soliton microcomb, an erbium-doped fiber amplifier that amplifies a C-band section of the soliton microcomb and a non-polarizing beam splitter that divides the soliton microcomb pulses into a reference arm pulse and a measurement arm pulse for an interferometer and recombines the reference arm pulse and the measurement arm pulse into a recombined beam upon their return.

Apparatus and methods are presented for enhancing the acquisition speed or performance of Fourier domain optical coherence tomography. In preferred embodiments a plurality of wavelength combs containing interleaved selections of wavelengths from a multi-wavelength optical source are generated and projected onto a sample. In certain embodiments the wavelength combs are projected simultaneously onto a plurality of regions of the sample, while in other embodiments the wavelength combs are projected sequentially onto the sample. Light in the wavelength combs reflected or scattered from the sample is detected in a single frame of a sensor array, and the detected light processed to obtain a tomographic profile of the sample. In preferred embodiments the wavelength comb generator comprises a wavelength interleaver in the form of a retro-reflective prism array for imparting different displacements to different selections of wavelengths from the optical source.

A digital measuring device implemented on a photonic integrated circuit, the digital measuring device including a laser source configured to provide light, a first ring resonator configured to produce a first frequency comb of light from the laser source, wherein at least a portion of the first frequency comb of light is directed at a moving object, a local oscillator configured to provide a reference beam, at least one waveguide structure configured to combine the reference beam with light reflected from the moving object to produce a measurement beam, a first multiplexer configured to split the measurement beam into a plurality of channels spaced in frequency, and a plurality of detectors configured to detect an intensity value of each channel of the plurality of channels to measure a distance between the digital measuring device and the moving object.

Apparatus and methods are presented for enhancing the acquisition speed or performance of Fourier domain optical coherence tomography. In preferred embodiments a plurality of wavelength combs containing interleaved selections of wavelengths from a multi-wavelength optical source are generated and projected onto a sample. In certain embodiments the wavelength combs are projected simultaneously onto a plurality of regions of the sample, while in other embodiments the wavelength combs are projected sequentially onto the sample. Light in the wavelength combs reflected or scattered from the sample is detected in a single frame of a sensor array, and the detected light processed to obtain a tomographic profile of the sample. In preferred embodiments the wavelength comb generator comprises a wavelength interleaver in the form of a retro-reflective prism array for imparting different displacements to different selections of wavelengths from the optical source.