Apparatuses, systems, and methods for Raman spectroscopy are described. In certain implementations, a spectrometer is provided. The spectrometer may include a plurality of optical elements, comprising an entrance aperture, a collimating element, a volume phase holographic grating, a focusing element, and a detector array. The plurality of optical elements are configured to transfer the light beam from the entrance aperture to the detector array with a high transfer efficiency over a preselected spectral band.

Swept-source Raman spectroscopy uses a tunable laser and a fixed-wavelength detector instead of a spectrometer or interferometer to perform Raman spectroscopy with the throughput advantage of Fourier transform Raman spectroscopy without bulky optics or moving mirrors. Although the tunable laser can be larger and more costly than a fixed wavelength diode laser used in other Raman systems, it is possible to split and switch the laser light to multiple ports simultaneously and/or sequentially. Each site can be monitored by its own fixed-wavelength detector. This architecture can be scaled by cascading fiber switches and/or couplers between the tunable laser and measurement sites. By multiplexing measurements at different sites, it is possible to monitor many sites at once. Moreover, each site can be meters to kilometers from the tunable laser. This makes it possible to perform swept-source Raman spectroscopy at many points across a continuous flow manufacturing environment with a single laser.

Swept-source Raman spectroscopy uses a tunable laser and a fixed-wavelength detector instead of a spectrometer or interferometer to perform Raman spectroscopy with the throughput advantage of Fourier transform Raman spectroscopy without bulky optics or moving mirrors. Although the tunable laser can be larger and more costly than a fixed wavelength diode laser used in other Raman systems, it is possible to split and switch the laser light to multiple ports simultaneously and/or sequentially. Each site can be monitored by its own fixed-wavelength detector. This architecture can be scaled by cascading fiber switches and/or couplers between the tunable laser and measurement sites. By multiplexing measurements at different sites, it is possible to monitor many sites at once. Moreover, each site can be meters to kilometers from the tunable laser. This makes it possible to perform swept-source Raman spectroscopy at many points across a continuous flow manufacturing environment with a single laser.

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.

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.

A method for phase contrasting-correlation spectroscopy: converting an incident linearly polarized light into two polarized components (polarized divergent and convergent components, wherein the polarized divergent component is orthogonal to the polarized convergent component), focusing each of the polarized divergent component and the polarized convergent component into a focal plane, thereby producing two focus planes constituting a reference focus (RF) plane and a sample focus (SF) plane; placing a sample at the SF plane and ambient conditions of the sample at the RF plane, resulting in a phase shift between the two polarized components; reconstituting the two phase-shifted polarized components into a phase-shifted linearly polarized light; detecting the phase-shifted linearly polarized light; calculating phase and intensity of the sample from the phase-shifted linearly polarized light; establishing an autocorrelation of phase and intensity of the phase-shifted linearly polarized light; and generating correlograms of intensity and phase of the phase-shifted linearly polarized light.

Disclosed is an assay for determining resistance in a target cell or tissue to a therapy associated with cellular stress using chemical microscopy and high-throughput single cell analysis to determine functional metabolic alteration, including determining metabolic reprogramming in a target cell or tissue to a therapy associated with cellular stress, and methods of using the assays.

A small, handheld Raman spectrometer device can be built from a laser, lenses, and a diffraction grating configured in a right-angle Raman spectroscopy geometry, and used in conjunction with a cell-phone camera to record the Raman spectra. The cell-phone-based Raman spectrometer system is suited to performing in-situ measurements of chemical and biological molecules.

A small, handheld Raman spectrometer device can be built from a laser, lenses, and a diffraction grating configured in a right-angle Raman spectroscopy geometry, and used in conjunction with a cell-phone camera to record the Raman spectra. The cell-phone-based Raman spectrometer system is suited to performing in-situ measurements of chemical and biological molecules.

A polarized Raman Spectrometric system for defining parameters of a polycrystaline material, the system comprises a polarized Raman Spectrometric apparatus, a computer-controlled sample stage for positioning a sample at different locations, and a computer comprising a processor and an associated memory. The polarized Raman Spectrometric apparatus generates signal(s) from either small sized spots at multiple locations on a sample or from an elongated line-shaped points on the sample, and the processor analyzes the signal(s) to define the parameters of said polycrystalline material.