In a general aspect, a method is presented for increasing the measurement precision of an optical instrument. The method includes determining, based on optical data and environmental data, a measured value of an optical property measured by the optical instrument. The optical instrument includes an optical path and a sensor configured to measure an environmental parameter. The method also includes determining a predicted value of the optical property based on a model representing time evolution of the optical instrument. The method additionally includes calculating an effective value of the optical property based on the measured value, the predicted value, and a Kalman gain. The Kalman gain is based on respective uncertainties in the measured and predicted values and defines a relative weighting of the measured and predicted values in the effective value.

The present invention relates to a method for the non-invasive optical characterization of a heterogeneous medium, comprising: a step of illuminating, by means of a series of incident light waves, a given field of view of the heterogeneous medium, positioned in a focal plane of a microscope objective (30); a step of determining a first distortion matrix (D.sub.ur, D.sub.rr) in an observation basis defined between a conjugate plane of the focal plane (FP) and an observation plane, said first distortion matrix corresponding, in a correction basis defined between a conjugate plane of the focal plane and an aberration correction plane, to the term-by-term matrix product of a first reflection matrix (R.sub.ur) of the field of view, determined in the correction basis, with the phase conjugate matrix of a reference reflection matrix, defined for a model medium, in said correction basis; and a step of determining, from the first distortion matrix, at least one mapping of a physical parameter of the heterogeneous medium.

Embodiments of systems and methods for measuring a surface topography of a semiconductor structure are disclosed. In certain examples, a plurality of interference signals, each corresponding to a respective one of a plurality of positions on a surface of the semiconductor structure, are measured. Calibration signals, associated with a baseline region corresponding to a first category of a plurality of categories and a calibrated region corresponding to a second category of the plurality of categories, are measured. A surface height offset, associated with the baseline region and the calibrated region, is determined based on original surface heights and the calibration signals. The original surface heights are determined based on the plurality of interference signals corresponding to the baseline region and the calibrated region. The surface topography of the semiconductor structure is characterized based, at least in part, on the surface height offset and the original surface heights.

The present invention relates to a method for the non-invasive optical characterization of a heterogeneous medium, comprising: a step of illuminating, by means of a series of incident light waves, a given field of view of the heterogeneous medium, positioned in a focal plane of a microscope objective (30); a step of determining a first distortion matrix (D.sub.ur, D.sub.rr) in an observation basis defined between a conjugate plane of the focal plane (FP) and an observation plane, said first distortion matrix corresponding, in a correction basis defined between a conjugate plane of the focal plane and an aberration correction plane, to the term-by-term matrix product of a first reflection matrix (R.sub.ur) of the field of view, determined in the correction basis, with the phase conjugate matrix of a reference reflection matrix, defined for a model medium, in said correction basis; and a step of determining, from the first distortion matrix, at least one mapping of a physical parameter of the heterogeneous medium.

An exemplary system, method, and computer-accessible medium for generating an image(s) of an three-dimensional anatomical flow map(s) can include receiving an optical coherence tomography (“OCT”) signal(s), splitting the OCT signal(s) into a plurality of subspectra, averaging the plurality of subspectra, and generating the image(s) of the three-dimensional anatomical flow map(s) based on the averaged subspectra. The OCT signal(s) can be a swept-source OCT signal. The OCT signal(s) can be split into the subspectra based on a Hamming window. The Hamming distance window can be optimized to minimize a nearest side lobe for each of the subspectra. A position of at least one of the subspectra can be shifted prior to averaging the subspectra. The position of all but one of the subspectra can be shifted prior to averaging the subspectra.

Embodiments of systems and methods for measuring a surface topography of a semiconductor chip are disclosed. In an example, a method for measuring a surface topography of a semiconductor chip is disclosed. A plurality of interference signals each corresponding to a respective one of a plurality of positions on a surface of the semiconductor chip are received by at least one processor. The plurality of interference signals are transformed by the at least one processor into a plurality of spectrum signals each corresponding to the respective one of the positions on the surface of the semiconductor chip. The spectrum signals are classified by the at least one processor into a plurality of categories using a model. Each of the categories corresponds to a region having a same material on the surface of the semiconductor chip. A surface height offset between a surface baseline and at least one of the categories is determined by the at least one processor based, at least in part, on a calibration signal associated with the region corresponding to the at least one of the categories. The surface topography of the semiconductor chip is characterized by the at least one processor based, at least in part, on the surface height offset and the interference signals.

Embodiments of systems and methods for measuring a surface topography of a semiconductor chip are disclosed. In an example, a method for measuring a surface topography of a semiconductor chip is disclosed. A plurality of interference signals each corresponding to a respective one of a plurality of positions on a surface of the semiconductor chip are received by at least one processor. The interference signals are classified by the at least one processor into a plurality of categories using a model. Each of the categories corresponds to a region having a same material on the surface of the semiconductor chip. A surface height offset between a surface baseline and at least one of the categories is determined by the at least one processor based, at least in part, on a calibration signal associated with the region corresponding to the at least one of the categories. The surface topography of the semiconductor chip is characterized by the at least one processor based, at least in part, on the surface height offset and the interference signals.

Embodiments of systems for classifying interference signals are disclosed. In an example, a system for classifying interference signals includes an interferometer including a light source and a detector, and at least one processor. The interferometer is configured to provide a plurality of interference signals each corresponding to a respective one of a plurality of positions on a surface of a semiconductor chip. A spectrum of the light source is greater than a spectrum of white light. The at least one processor is configured to classify the interference signals into a plurality of categories using a model. Each of the categories corresponds to a region having a same material on the surface of the semiconductor chip.

Embodiments of systems and methods for measuring a surface topography of a semiconductor chip are disclosed. In an example, a method for measuring a surface topography of a semiconductor chip is disclosed. A plurality of interference signals and a plurality of spectrum signals are received by at least one processor. Each of the interference signals and spectrum signals corresponds to a respective one of a plurality of positions on a surface of the semiconductor chip. The spectrum signals are classified by the at least one processor into a plurality of categories using a model. Each of the categories corresponds to a region having a same material on the surface of the semiconductor chip. A surface height offset between a surface baseline and at least one of the categories is determined by the at least one processor based, at least in part, on a calibration signal associated with the region corresponding to the at least one of the categories. The surface topography of the semiconductor chip is characterized by the at least one processor based, at least in part, on the surface height offset and the interference signals.

An electro-optical system has a laser drive electronic circuit, a laser light source and an optical interferometer, forming a closed loop. The laser drive electronic circuit is arranged to receive a reference frequency as input, and a beat frequency as feedback. The laser drive electronic circuit generates a drive output based on a phase difference between the reference frequency and the beat frequency. The optical interferometer, coupled to the laser light, generates optical energy at the beat frequency.