Methods, systems and devices are described that improve optical spectroscopic techniques and particularly those that involve externally dispersed interferometer (EDI) techniques that result in an output spectrum having improved stability characteristics. The output spectrum minimizes the unwanted shifts in wavelength when the spectrograph component of the EDI instrument is under stresses that would otherwise shift or distort the wavelength positions of the spectrum.

Disclosed is an optical sensor, including an external cavity laser configured to output sensing light and reference light; and a photodetector configured to detect a beating signal by an interference of the sensing light and the reference light output from the external cavity laser, in which the external cavity laser includes a reflecting filter including a sensing grating, to which a sensing object is attachable, and a reference grating, which is disposed on the same plane as that of the sensing grating, and outputs sensing light reflected from the sensing grating and reference light reflected from the reference grating. Accordingly, the optical sensor does not require a high-resolution spectroscope and has improved resolution and sensitivity.

A system is described that combines spectropolarimetry with scatterometry. The system uses an annular mirror and liquid crystal devices to control the angle of the incident light cone, the polarization and wavelength, an imaging setup and one or more video cameras so that spectroscopic-polarimetric-scatterometric images can be grabbed rapidly. The system is also designed to incorporate additional imaging modes such as interference, phase contrast, fluorescence and Raman spectropolarimetric imaging.

A system is described that combines spectropolarimetry with scatterometry. The system uses an annular mirror and liquid crystal devices to control the angle of the incident light cone, the polarization and wavelength, an imaging setup and one or more video cameras so that spectroseopic-polarimetric-scatterometric images can be grabbed rapidly. The system is also designed to incorporate additional imaging modes such as interference, phase contrast, fluorescence and Raman spectropolarimetric imaging.

A spectrum measuring device including a ribbon element, a light detection element, and circuitry. The ribbon element includes a first light reflector including a plurality of first light reflection surfaces configured to be translated in an out-of-plane direction, and a second light reflector including a plurality of second light reflection surfaces that are fixed. The circuitry supplies a drive signal to the ribbon element in such a manner that a change of a displacement amount difference between the first light reflection surfaces and the second light reflection surfaces corresponds to a predetermined frequency; and acquires the light quantity data detected by the light detection element at a predetermined sampling frequency.

A spectrum measuring device including a ribbon element, a light detection element, and circuitry. The ribbon element includes a first light reflector including a plurality of first light reflection surfaces configured to be translated in an out-of-plane direction, and a second light reflector including a plurality of second light reflection surfaces that are fixed. The circuitry supplies a drive signal to the ribbon element in such a manner that a change of a displacement amount difference between the first light reflection surfaces and the second light reflection surfaces corresponds to a predetermined frequency; and acquires the light quantity data detected by the light detection element at a predetermined sampling frequency.

A device and method for surface height profiling are presented. The device has a source with a source slit through which light is provided. The device includes an objective lens having a reference surface. The objective lens is configured to illuminate a sample with test light from the source and to combine test light reflected from the sample with reference light reflected from the reference surface to form combined light. A spectrometer is positioned to receive the combined light at an entrance slit. The spectrometer is configured to image the combined light as a 2D image with a wavelength dimension and a spatial position dimension. A processor in electrical communication with the spectrometer is programmed to receive a signal representing the 2D image and to determine a surface height profile of the sample based on the signal.

Optical systems include a first optical element featuring a first substrate, a partially-reflective coating disposed on a first surface of the first substrate, a first meta-material layer positioned on or adjacent to a first surface of the first substrate and including a structure that defines a continuous phase gradient along a first direction parallel to the first surface of the first substrate, and a second optical element featuring a second substrate and a second meta-material layer positioned on or adjacent to a first surface of the second substrate and comprising a structure that defines a continuous phase gradient along a second direction parallel to the first surface of the first substrate, where at least one surface of the second optical element is curved along the second direction.

The present disclosure provides a radio frequency tagging optical spectrometer, comprising: a dynamic dispersion device, the dynamic dispersion device receiving a beam comprising more than two wavelength components and being driven by driving radio frequency signals, and the dynamic dispersion device encoding the intensity of each wavelength component into the amplitude of a different beat radio frequency signal based on different driving radio frequency signals, wherein the beat frequency of the different beat radio frequency signal is equal to the frequency of the corresponding driving radio frequency signal; a single-channel photodetector for detecting the sum of beat radio frequency signals formed by adding all the beat radio frequency signals; and a processing unit for performing Fourier transform on the sum of the beat radio frequency signals to obtain a spectrum or an associated radio frequency spectrum by which the optical spectrum is obtained.

Provided are a device (4) and a method for online measuring a spectrum for a laser device. The device (4) for online measuring a spectrum for a laser device includes: a first optical path assembly (G1) and a second optical path assembly (G2), and the second optical path assembly (G2) and the first optical path assembly (G1) constitute a measurement optical path. The second optical path assembly (G2) includes: an FP etalon (15) and a grating (18). The homogenized laser beam passes through the FP etalon (15) to generate an interference fringe. The grating (18) is arranged after the FP etalon (15), or is arranged before the FP etalon (15) in the measurement optical path, and is configured to disperse the laser beam passing through the FP etalon (15).