The present subject matter at least provides an apparatus for characterization of a slab of a material. The apparatus comprises two or more frequency-domain optical-coherence tomography (FD-OCT) probes configured for irradiating the slab of material, and detecting radiation reflected from the slab of material or transmitted there-through. Further, a centralized actuation-mechanism is connected to the OCT probes for simultaneously actuating elements in each of the OCT probes to cause a synchronized detection of the radiation from the slab of material. A spectral-analysis module is provided for analyzing at least an interference pattern with respect to each of the OCT probes to thereby determine at least one of thickness and topography of the slab of the material. Further, in some embodiments, the slab of material may include a passivation layer. The apparatus may be configured to determine a thickness of the passivation layer.

The present subject matter at least provides an apparatus for inspecting a slab of material including a passivation layer. The apparatus includes a frequency-domain optical-coherence tomography (OCT) probe configured to irradiate the slab of material, and detect radiation reflected from the slab of material. The apparatus also includes a spectral-analysis module configured to analyze at least an interference pattern with respect to the OCT probe to thereby determine a thickness of the slab of the material. The apparatus also includes a thin-film gauge configure to determine a thickness of the passivation layer such that the determined thickness of the slab of material may be adjusted baes on the thickness of the passivation layer.

The invention relates to an OCT system comprising an OCT light source, an OCT evaluation unit, a first OCT light guide, a second OCT light guide and a changeover module. The light from the OCT light source passes through the changeover module. In a first state of the changeover module, the OCT light is passed to an entry end of the first OCT light guide. In a second state of the changeover module, the OCT light is passed to an entry end of the second OCT light guide. A scanning device assigned to the first OCT light guide is arranged between the changeover module and the object plane. The OCT system according to the invention can be used in a flexible manner.

The invention relates to a device for optical measurement of a thickness of an intransparent layer on a substrate, comprising first means for optical distance measurement configured to measure a first distance between a first reference plane and a first surface of the intransparent layer, and second means for optical distance measurement configured to measure a second distance between a second reference plane and a second surface of the intransparent layer. The second means measures a third distance between the second reference plane and a surface of the substrate. The thickness of the intransparent layer is computed from the first distance and the second distance. The measurement of the third distance is used to take into account the influence of the optical effect of the substrate on the distance measurement of the second distance. The invention also relates to a method for optical measurement of a thickness of an intransparent layer on a substrate.

According to an aspect of one or more embodiments, the present subject matter describes an apparatus for inspecting a slab of a material. The apparatus comprises a first and second low-coherence sensor configured to irradiate a first and second side of a slab of material with first light having a first polarization and second light having a second polarization, and thereafter configured to detect a reflection. A first polarizer is configured to allow reflected first light having the first polarization to pass through, and reject a second-light cross-talk portion having the second polarization. A second polarizer is configured to allow reflected second light having the second polarization to pass through, and reject a first-light cross-talk portion having the first polarization. Further, a computing-system is configured to receive signals representing the reflected first light and the reflected second light; and analyze the reflected first light and the reflected second light.

A deformometer includes: a cavity body; entry and exit optical cavity optics, such that the optical cavity produces filtered combined light from combined light; a first laser that provides first light; a second laser that provides second light; an optical combiner that: receives the first light; receives the second light; combines the first light and the second light; produces combined light from the first light and the second light; and communicates the combined light to the entry optical cavity optic; a beam splitter that: receives the filtered combined light; splits the filtered combined light; a first light detector in optical communication with the beam splitter and that: receives the first filtered light from the beam splitter; and produces a first cavity signal from the first filtered light; and a second light detector that: receives the second filtered light; and produces a second cavity signal from the second filtered light.

A deformometer includes: a cavity body; entry and exit optical cavity optics, such that the optical cavity produces filtered combined light from combined light; a first laser that provides first light; a second laser that provides second light; an optical combiner that: receives the first light; receives the second light; combines the first light and the second light; produces combined light from the first light and the second light; and communicates the combined light to the entry optical cavity optic; a beam splitter that: receives the filtered combined light; splits the filtered combined light; a first light detector in optical communication with the beam splitter and that: receives the first filtered light from the beam splitter; and produces a first cavity signal from the first filtered light; and a second light detector that: receives the second filtered light; and produces a second cavity signal from the second filtered light.

A deformometer includes: a cavity body; entry and exit optical cavity optics, such that the optical cavity produces filtered combined light from combined light; a first laser that provides first light; a second laser that provides second light; an optical combiner that: receives the first light; receives the second light; combines the first light and the second light; produces combined light from the first light and the second light; and communicates the combined light to the entry optical cavity optic; a beam splitter that: receives the filtered combined light; splits the filtered combined light; a first light detector in optical communication with the beam splitter and that: receives the first filtered light from the beam splitter; and produces a first cavity signal from the first filtered light; and a second light detector that: receives the second filtered light; and produces a second cavity signal from the second filtered light.

The present subject matter at-least provides an apparatus for characterization of a slab of a material. The apparatus comprises a plurality of frequency-domain optical-coherence tomography (FD-OCT) probes configured for irradiating the slab of material at at-least one location, and detecting radiation reflected from the slab of material or transmitted there-through. Further, a centralized actuation-mechanism is connected to the plurality of OCT probes for simultaneously actuating one or more elements in each of said OCT probes to at-least cause a synchronized detection of the radiation from the slab of material. A spectral-analysis module is provided for analyzing at least an interference pattern with respect to each of said OCT probes to thereby determine at least one of thickness and topography of the slab of the material.

According to an aspect of one or more embodiments, the present subject matter describes an apparatus for inspecting a slab of a material. The apparatus comprises a first and second low-coherence sensor configured to irradiate a first and second side of a slab of material with first light having a first polarization and second light having a second polarization, and thereafter configured to detect a reflection. A first polarizer is configured to allow reflected first light having the first polarization to pass through, and reject a second-light cross-talk portion having the second polarization. A second polarizer is configured to allow reflected second light having the second polarization to pass through, and reject a first-light cross-talk portion having the first polarization. Further, a computing-system is configured to receive signals representing the reflected first light and the reflected second light; and analyze the reflected first light and the reflected second light.