Interferometer system, including optical means (2, 3, 4, 5) arranged for directing light along a first interferometer path and (separate) second interferometer path, and for combining the light for allowing interferometry, characterized in that the first interferometer path (PI) is provided with a first light transmitting structure (10) having a rotational position that is adjustable with respect to an optical axis of the first path.

An optical measurement method with an optical measurement apparatus including an irradiation optical system and a measurement optical system is provided. The optical measurement method includes obtaining a distribution of actually measured values when angles of incidence are different for the same sample, calculating a modification factor depending on an angle of incidence on the measurement optical system from each measurement point in association with a region in the two-dimensional image corresponding to each measurement point in the measurement target irradiated with the measurement light, and calculating optical characteristics including a refractive index of the sample based on a group of pixel values in one row or a plurality of rows along any one direction in the distribution of the actually measured values and a corresponding modification factor.

An optical measuring system for a measuring machine includes at least two scanning devices for intermittently moving through alternately timed sequences of static measuring positions at which a measuring beam is directed to and from a test object. An optical switch selectively routes the measuring beam through any one of the scanning devices that has settled into one of the static measuring positions.

An optical measurement apparatus includes an irradiation optical system which linearly irradiates a measurement target with measurement light having a certain wavelength range, a measurement optical system which receives linear measurement interference light which is transmitted light or reflected light originating from the measurement target as a result of irradiation with the measurement light, and a processing device. The processing device includes a first calculation module that calculates a modification factor depending on with an angle of incidence on the measurement optical system from each measurement point in association with a region in the two-dimensional image corresponding to each measurement point in the measurement target irradiated with the measurement light and a second calculation module that calculates optical characteristics of the measurement target by applying the corresponding modification factor to a value for each pixel included in the two-dimensional image.

Provided is a technology for acquiring a tomographic image under an appropriate focusing condition by an OCT apparatus. A control apparatus configured to control a tomographic image acquiring unit configured to acquire a tomographic image includes: a setting unit configured to set a focusing area on an object to be inspected; a condition acquiring unit configured to acquire a first focusing condition for a front image acquiring unit with respect to the focusing area, which is set in a partial region of a front image of the object to be inspected acquired by the front image acquiring unit, and is narrower than an image acquiring area of the front image; and a control unit configured to cause the tomographic image acquiring unit to acquire the tomographic image under a second focusing condition in accordance with the acquired first focusing condition.

An optical measurement apparatus includes an irradiation optical system which linearly irradiates a measurement target with measurement light having a certain wavelength range, a measurement optical system which receives linear measurement interference light which is transmitted light or reflected light originating from the measurement target as a result of irradiation with the measurement light, and a processing device. The processing device includes a first calculation module that calculates a modification factor depending on with an angle of incidence on the measurement optical system from each measurement point in association with a region in the two-dimensional image corresponding to each measurement point in the measurement target irradiated with the measurement light and a second calculation module that calculates optical characteristics of the measurement target by applying the corresponding modification factor to a value for each pixel included in the two-dimensional image.

An optical measurement method with an optical measurement apparatus including an irradiation optical system and a measurement optical system is provided. The optical measurement method includes obtaining a distribution of actually measured values when angles of incidence are different for the same sample, calculating a modification factor depending on an angle of incidence on the measurement optical system from each measurement point in association with a region in the two-dimensional image corresponding to each measurement point in the measurement target irradiated with the measurement light, and calculating optical characteristics including a refractive index of the sample based on a group of pixel values in one row or a plurality of rows along any one direction in the distribution of the actually measured values and a corresponding modification factor.

Metrology tools and methods of obtaining a full-field optical field of an optical device to determine multiple metrology metrics of the optical device are provided. A metrology tool is utilized to split a light beam into a first light path and a second light path. The first light path and the second light path are combined into a combined light beam and delivered to the detector. The detector measures the intensity of the combined light beam. A first equation and second equation are utilized in combination with the intensity measurements to determine an amplitude and phase ? at a reference point directly adjacent to a second surface of the at least one optical device.

A system for measuring a target grating includes an illumination source, a reference transmission grating, a pupil filter, and a detector. The illumination source is disposed to generate an incident light beam that illuminates the reference transmission grating. The reference transmission grating splits the incident light beam into a plurality of diffraction orders. The plurality of diffraction orders interrogates a target grating. The reference transmission grating and the target grating are parallel. The pupil filter allows transmission of a subset of diffraction orders of light that has been diffracted and/or reflected from the target grating after being split again by passing through the reference transmission grating. The detector takes a measurement of the subset of diffraction orders of light after transmission through the pupil filter.

Interferometric speckle visibility spectroscopy methods, systems, and non-transitory computer readable media for recovering sample speckle field data or a speckle field pattern from an off-axis interferogram recorded by one or more sensors over an exposure time and determining sample dynamics of a sample being analyzed from speckle statistics of the speckle field data or the speckle field pattern.