Abstract: In a method and apparatus for determining the height of a plurality of spatial positions on a surface of a specimen, a light beam is projected on the surface. The surface is scanned along an optical axis in different scanning positions. The light reflected by the surface is detected in scanning positions with a spatial pattern having corresponding spatial pattern positions. From the detected light for each spatial position of the surface, an envelope curve of intensity values corresponding to scanning positions is determined. A maximum of the envelope curve and its corresponding scanning position being representative of the height of the spatial position of the surface is selected. The spatial pattern is moved in a sequence of 2n steps (n>2) in a first and a second spatial direction over a distance of ¼ and 1/n pattern wavelength, respectively.

Abstract: A structured illumination microscopy optical arrangement includes a projection path and an imaging path. The imaging path includes an imaging sensor and imaging optical elements. The projection path includes a light generator, a pattern generating element such as a spatial light modulator (SLM), and projection optical elements including an output lens and a projector artifact suppression element (PASE) located in the projection path between the SLM and the output lens. The PASE may include birefringent material which splits respective light rays of the structured illumination pattern source light to provide at least one replication of the structured illumination pattern with an offset transverse to the projection path. The offset replication of the structured illumination pattern increases the accuracy of the system by reducing spatial harmonic errors and spurious intensity variations due to projector pixel gap artifacts which may otherwise produce errors in resulting Z-height measurements.

Abstract: In a method and apparatus for determining the height of a plurality of spatial positions on a surface of a specimen, a light beam is projected on the surface. The light beam has a sinusoidal spatial pattern in at least two directions perpendicular to an optical axis of the light beam, and which is moved to different spatial pattern positions. The surface is scanned along the optical axis in different scanning positions. A fixed relationship between a moving distance between subsequent spatial pattern positions, and a scanning distance between subsequent scanning positions exists. The light reflected by the surface is detected in scanning positions with the spatial pattern having corresponding spatial pattern positions. From the detected light for each spatial position of the surface, an envelope curve of intensity values corresponding to scanning positions is determined.

Abstract: A structured illumination microscopy optical arrangement includes a projection path and an imaging path. The imaging path includes an imaging sensor and imaging optical elements. The projection path includes a light generator, a pattern generating element such as a spatial light modulator (SLM), and projection optical elements including an output lens and a projector artifact suppression element (PASE) located in the projection path between the SLM and the output lens. The PASE may include birefringent material which splits respective light rays of the structured illumination pattern source light to provide at least one replication of the structured illumination pattern with an offset transverse to the projection path. The offset replication of the structured illumination pattern increases the accuracy of the system by reducing spatial harmonic errors and spurious intensity variations due to projector pixel gap artifacts which may otherwise produce errors in resulting Z-height measurements.

Abstract: The invention relates to a method and an apparatus for determining a height of a number of spatial positions on a sample, defining a height map of a surface of said sample. The method can involve irradiating the surface of the sample with light including a spatial periodic pattern in a direction perpendicular to an optical axis and moving parallel to the pattern, scanning the surface in the direction of the optical axis for each position of the surface and detecting the light reflected by the sample by a detector during the scanning. In any scanning position, only a single image is taken, and the scanning speed has a predetermined relation to the phase of the periodic pattern. Analyzing an output signal of the detector can involve, for each spatial position of the detector, determining of an amplitude of the signal detected during the scanning and determining a scanning location where the amplitude is maximal.

Abstract: The invention relates to a method and an apparatus for determining a height of a number of spatial positions on a sample, defining a height map of a surface of said sample. The method can involve irradiating the surface of the sample with light including a spatial periodic pattern in a direction perpendicular to an optical axis and moving parallel to the pattern, scanning the surface in the direction of the optical axis for each position of the surface and detecting the light reflected by the sample by a detector during the scanning. In any scanning position, only a single image is taken, and the scanning speed has a predetermined relation to the phase of the periodic pattern. Analyzing an output signal of the detector can involve, for each spatial position of the detector, determining of an amplitude of the signal detected during the scanning and determining a scanning location where the amplitude is maximal.