A wavelength-swept light source projects a light beam. An interferometer includes a splitting unit that splits the light beam projected from the wavelength-swept light source into light beams radiated toward a plurality of spots on a measurement target. Each of the interference beam is generated by interference between a measurement beam radiated toward the measurement target and reflected at the measurement beam, and a reference beam passing through an optical path that is at least partially different from an optical path of the measurement beam. A light-receiving unit receives the interference beams from the interferometer. A processor calculates distance to the measurement target by associating a detected peak of the interference beams with one of the spots. The optical path length difference between the measurement target and the reference beam is made different among the light beams split in correspondence with the plurality of spots.

A method of determining information indicative of a material attribute of a composition, wherein the method comprises manufacturing the composition using a thermal manufacturing process, detecting detection data from the composition by low coherence interferometry during the manufacturing, in particular during said thermal manufacturing process, and determining the information based on the detected detection data.

A method of determining information indicative of a material attribute of a composition, wherein the method comprises manufacturing the composition using a thermal manufacturing process, detecting detection data from the composition by low coherence interferometry during the manufacturing, in particular during said thermal manufacturing process, and determining the information based on the detected detection data.

A light source projects a light beam. An interferometer includes a splitting unit that splits the light beam. The interferometer generates interference beams with the respective split light beams. Each of the interference beam is generated by interference between a measurement beam radiated toward the measurement target and reflected at the measurement beam and a reference beam passing through an optical path. A light-receiving unit receives the interference beams. A processor calculates a distance to the measurement target by associating at least one detected peak with at least one of the spots in accordance with a mirror surface mode or a rough surface mode. The optical path length difference is made different among the split light beams. In the mirror surface mode, the processor uses a distance calculated based on a peak corresponding to a spot for which the optical path length difference is shortest.

A distance measurement device includes: a signal acquisition unit to acquire an electric signal based on interference light from an optical sensor device that splits sweep light having a periodically changing frequency into reference light and irradiation light to be emitted toward an object to be measured, irradiates the object with the irradiation light, generates interference light by causing the reference light to interfere with reflected light that is the irradiation light reflected by the object, and generates the electric signal based on the generated interference light; a frequency calculation unit to calculate, on the basis of the electric signal based on the interference light, a peak frequency of the electric signal using LASSO regression; a distance measurement unit to measure, on the basis of the peak frequency, a distance from a predetermined reference point to the object; and a distance output unit to output distance information indicating the distance.

A fast measurement method for micro-nano deep groove structure based on white light interference, including: establishing a white light interference system, using the white light interference system to measure the structure of the groove, the CCD camera collects and obtains multiple groups of groove interferograms and the serial number corresponding to each groove interferogram in each group; processing each group of groove interferograms of the groove sample to obtain the maximum contrast of each group of groove interferograms and the 3D reconstruction diagram of the local structure; extracting the interface reconstruction diagram in the 3D reconstruction diagram of the local structure according to each group of the groove interferograms; after splicing the interface reconstruction diagrams corresponding to all groups of groove interferograms, obtaining a 3D structural reconstruction diagram of the groove sample, and measuring the depth and width of the groove sample according to the 3D structural reconstruction diagram.

An optical device provided with an optical parts position adjusting and fixing device for adjusting and fixing the position of the optical parts moving in an optical axis direction, wherein the position adjusting and fixing device is provided with a long slotted hole extended in the optical axis direction formed on a side surface of the optical parts; a fixing means which is mounted on an object to be fixed of the optical parts and which is movable along the long slotted hole; a non-penetrating screw hole formed in the fixing means and which is divided by a slit; and a screw which is screwed into the screw hole and spreads the slit when screwed into the screw hole so as to press the outer surface of the fixing means against the inner surface of the long slotted hole.

A method for measuring interfaces of an optical element, forming part of a plurality of similar elements including at least one reference optical element, the method implemented by a device, the method including: relative positioning of each reference optical element and the measurement beam, to allow a measurement of interfaces of each reference optical element; acquisition of a reference image, of each reference element; positioning of the measured optical element to allow acquisition of a measurement image, of the optical element to be measured; determining a difference of position in a field of view of the measured element with respect to each reference optical element, based on the reference and measurement images; adjusting the position of the measured optical element in the field of view to cancel the difference of position; and measuring the interfaces of the measured optical element by the measurement beam.

A method for measuring interfaces of an optical element, forming part of a plurality of similar elements including at least one reference optical element, the method implemented by a device, the method including: relative positioning of each reference optical element and the measurement beam, to allow a measurement of interfaces of each reference optical element; acquisition of a reference image, of each reference element; positioning of the measured optical element to allow acquisition of a measurement image, of the optical element to be measured; determining a difference of position in a field of view of the measured element with respect to each reference optical element, based on the reference and measurement images; adjusting the position of the measured optical element in the field of view to cancel the difference of position; and measuring the interfaces of the measured optical element by the measurement beam.

Provided is a system for range detection including at least one beam source arrangement configured to provide illumination of certain coherence length, an optical arrangement, and a detection arrangement including at least one detector unit.