A method for determining a distance of a sample reference plane of a sample carrier from a reference plane of a microscope, the microscope including a sample stage for the sample carrier and a camera, comprises the following steps: taking an overview image of the sample carrier by means of the camera; evaluating the overview image and thus detecting at least one characteristic of the sample carrier; ascertaining contextual data of the characteristic from a data set; and determining the distance of the sample reference plane from the reference plane based on the characteristic and the contextual data of the sample carrier. A microscope configured to determine the distance of the sample reference plane of the sample carrier from the reference plane is also described.

An optical distance measuring apparatus includes: a scanning element scanning a coherent irradiation light from a light source and sending it to an object under measurement; a photo detector receiving the irradiation light modulated by being passed through the object under measurement in accordance with the scanning, and performing photoelectric conversion on the irradiation light; and a measuring unit obtaining phase information of the object under measurement based on a signal photoelectrically converted by the photo detector and a signal to be a reference for the scanning by the scanning element, and obtaining a measurement value regarding the object under measurement based on the phase information.

A spectroscope including: a spectral element that is configured to spectrally separate signal light; a first optical system that is configured to condense spectroscopic light spectrally separated by the spectral element; and an optical receiver that is configured to receive the spectroscopic light; wherein the optical receiver includes a plurality of regions different sensitivities with respect to a wavelength characteristics of the spectroscopic light.

A spectroscope including: a spectral element that is configured to spectrally separate signal light; a first optical system that is configured to condense spectroscopic light spectrally separated by the spectral element; and an optical receiver that is configured to receive the spectroscopic light; wherein the optical receiver includes a plurality of regions different sensitivities with respect to a wavelength characteristics of the spectroscopic light.

One or more embodiments are directed to apparatuses and methods of evaluating an endface of an optical communication link, such as a fiber optic cable. In at least one embodiment, a camera probe includes an imaging device that includes one or more feedback mechanisms, such as an alignment feedback mechanism that communicates alignment information regarding an alignment of the optical communication link under test with an image sensor of the camera probe. The alignment feedback mechanism may be visual and/or aural. The alignment feedback mechanism may provide directional information to the user indicative of a direction to move the imaging device relative to the optical communication link. In addition or alternatively, the feedback mechanism may include a focus feedback mechanism that communicates focus information regarding a focus of the endface in an obtained image of the endface.

One or more embodiments are directed to apparatuses and methods of evaluating an endface of an optical communication link, such as a fiber optic cable. In at least one embodiment, a camera probe includes an imaging device that includes one or more feedback mechanisms, such as an alignment feedback mechanism that communicates alignment information regarding an alignment of the optical communication link under test with an image sensor of the camera probe. The alignment feedback mechanism may be visual and/or aural. The alignment feedback mechanism may provide directional information to the user indicative of a direction to move the imaging device relative to the optical communication link. In addition or alternatively, the feedback mechanism may include a focus feedback mechanism that communicates focus information regarding a focus of the endface in an obtained image of the endface.

A method for measuring a surface parameter of copper foil exhibiting high correlation with high frequency characteristics, the method for measuring a surface parameter of copper foil including: (a) acquiring a surface profile on at least one surface of an untreated copper foil; (b) setting a cutoff value for an L filter based on the surface profile; (c) acquiring a surface profile on at least one surface of surface-treated copper foil originating from the untreated copper foil; (d) subjecting the surface profile of the surface-treated copper foil to filter processing, the filter processing including processing using an L filter with the cutoff value; and (e) calculating at least one of surface parameters defined by ISO25178 on the surface of the surface-treated copper foil based on the surface profile after the filter processing.

A method for measuring a surface parameter of copper foil exhibiting high correlation with high frequency characteristics, the method for measuring a surface parameter of copper foil including: (a) acquiring a surface profile on at least one surface of an untreated copper foil; (b) setting a cutoff value for an L filter based on the surface profile; (c) acquiring a surface profile on at least one surface of surface-treated copper foil originating from the untreated copper foil; (d) subjecting the surface profile of the surface-treated copper foil to filter processing, the filter processing including processing using an L filter with the cutoff value; and (e) calculating at least one of surface parameters defined by ISO25178 on the surface of the surface-treated copper foil based on the surface profile after the filter processing.

A method for mounting a sensor bearing unit providing a bearing and an impulse ring provided with a target holder and with a target mounted on an axial portion of the target holder. The method including measuring an eccentricity E.sub.1 between the target and the axial portion of the target holder, measuring an eccentricity E.sub.2 between a groove made in the bore of an inner ring of the bearing and the bore, introducing the target holder inside the groove, turning the target holder inside the groove to an angular position in which the eccentricity E.sub.total between the target and the bore of the inner ring is less than or equal to a predetermined value which is lower than the sum of the eccentricities E.sub.1 and E.sub.2, and securing the target holder inside the groove of the inner ring at the angular position.

A spectral confocal measurement device includes a light source portion, configured to emit a broad-spectrum light beam with a certain wavelength range in a first predetermined path; an optical sampling portion, configured to converge the broad-spectrum light beam emitted from the light source portion on different measurement surfaces of an object to be measured, and output a reflected light in a second predetermined path that is different from a reverse direction of the first predetermined path; and a measurement portion, configured to receive and process the reflected light from the optical sampling portion to obtain a measurement result. The device can improve measurement accuracy and reduce production costs. In addition, a spectral confocal measurement method is also provided.