Abstract: A technique determines a depth measurement associated with a scene captured by an image capture device. The technique receives at least first and second images of the scene, in which the first image is captured using at least one different camera parameter than that of the second image. At least first and second image patches are selected from the first and second images, respectively, the selected patches corresponding to a common part of the scene. The selected image patches are used to determine which of the selected image patches provides a more focused representation of the common part. At least one value is calculated based on a combination of data in the first and second image patches, the combination being dependent on the more focused image patch. The depth measurement of the common part of the scene is determined from the at least one calculated value.

Abstract: Disclosed is a method of determining at least one three-dimensional (3D) geometric parameter of an imaging device. A two-dimensional (2D) target image is provided having a plurality of alignment patterns. The target image is imaged with an imaging device to form a captured image. At least one pattern of the captured image is compared with a corresponding pattern of the target image. From the comparison, the geometric parameter of the imaging device is then determined. The alignment patterns include at least one of (i) one or more patterns comprising a 2D scale and rotation invariant basis function, (ii) one or more patterns comprising a 1D scale invariant basis function, and (iii) one or more patterns having a plurality of grey levels and comprising a plurality of superimposed sinusoidal patterns, the plurality of sinusoidal patterns having a plurality of predetermined discrete orientations.

Abstract: A method of determining a focus parameter for aligning a water in an exposure tool within a measurement tolerance required for the exposure tool, the exposure tool using a lens system for alignment. A test chart is provided having a sharp auto-correlation associated with the wafer. An image of the test chart is captured using a lens pupil mask having at least two phase ramps that are non-parallel. The captured image of the test charge is auto-correlated to determine the position of the test chart relative to a focal position of the lens system. The focus parameter for alignment of the wafer is determined using the determined position of the test chart, whereby the focus parameter is determined within the measurement tolerance required by the exposure tool.

Abstract: A technique determines a depth measurement associated with a scene captured by an image capture device. The technique receives at least first and second images of the scene, in which the first image is captured using at least one different camera parameter than that of the second image. At least first and second image patches are selected from the first and second images, respectively, the selected patches corresponding to a common part of the scene. The selected image patches are used to determine which of the selected image patches provides a more focused representation of the common part. At least one value is calculated based on a combination of data in the first and second image patches, the combination being dependent on the more focused image patch. The depth measurement of the common part of the scene is determined from the at least one calculated value.

Abstract: Disclosed is a method for determining a focus parameter for aligning a wafer (W) in an exposure tool (1000) within a measurement tolerance required for the exposure tool, the exposure tool using a lens system (EL) for alignment. The method provides a test chart (1410) associated with the wafer, the test chart having a sharp auto-correlation and then captures (1430), using a lens pupil mask (1420), an image of the test chart, the lens pupil mask having at least two phase ramps which are non-parallel. An auto-correlation (1520) is performed on the captured image (1510) of the test chart to determine the position of the test chart relative to a focal position of the lens system. The focus parameter is then determined (1530, 1540, 1550) for alignment of the wafer using the determined position of the test chart, whereby the focus parameter is determined within the measurement tolerance required by the exposure tool.

Abstract: Disclosed is a method of determining at least one three-dimensional (3D) geometric parameter of an imaging device. A two-dimensional (2D) target image is provided having a plurality of alignment patterns. The target image is imaged with an imaging device to form a captured image. At least one pattern of the captured image is compared with a corresponding pattern of the target image. From the comparison, the geometric parameter of the imaging device is then determined. The alignment patterns include at least one of (i) one or more patterns comprising a 2D scale and rotation invariant basis function, (ii) one or more patterns comprising a 1D scale invariant basis function, and (iii) one or more patterns having a plurality of grey levels and comprising a plurality of superimposed sinusoidal patterns, the plurality of sinusoidal patterns having a plurality of predetermined discrete orientations.