Abstract: A system and method for verification of nasogastric tube (NGT) placement is provided. A fiber optic light guide includes a proximal end with a light source connection and a distal end having a light emitting tip. The light guide is constructed and arranged for insertion into a lumen of the NGT. A stop that prevents the distal end of the light guide from exiting a distal end of the NGT. The stop is adapted to engage a connector on the proximal end of the NGT. The light emitting tip can comprises a radial emitter. The light source can emit light at approximately 650 nm with an output power of approximately 30W. The stop is located so that the distal end of the light guide is positioned at an offset from the distal end of the NGT when the stop engages the proximal end of the NGT.

Abstract: A machine vision inspection system acquires a plurality of images of a workpiece region of interest at various focus heights, and determines a Z-height (e.g., the best focus height) for the region of interest based on a focus peak determining data set for the region of interest. The focus peak determining data set is derived from the plurality of images. The machine vision inspection system also determines Z-height quality meta-data based on data derived from the plurality of images (e.g., based on the focus peak determining data set), and associates the Z-height quality meta-data with the corresponding Z-heights. The Z-height quality meta-data are usable to establish weighting factors that are used in association with the corresponding best focus Z-heights in subsequent operations that fit a workpiece surface representation to a plurality of the best focus Z-heights.

Abstract: A refined autofocus method provides optimized lighting between iterative autofocus operations, to reliably provide the best possible autofocus Z-height precision. The method includes a quantitative initial focus Z-height determination based on initial focus curve data from initial autofocus images acquired using initial light control parameters. Then, the camera is set at that initial focus Z-height such that well focused images are provided. Refined (optimized) light control parameters are then determined based on at least one respective image acquired using respective light control parameters at that Z-height, such that an image acquired using the refined light control parameters provides a near-optimum value for a contrast-related metric (e.g., a focus metric) at that Z-height. Then, refined autofocus images are acquired using the refined light control parameters and a refined precise Z-height is quantitatively determined base on the resulting focus curve.

Abstract: A machine vision inspection system acquires a plurality of images of a workpiece region of interest at various focus heights, and determines a Z-height (e.g., the best focus height) for the region of interest based on a focus peak determining data set for the region of interest. The focus peak determining data set is derived from the plurality of images. The machine vision inspection system also determines Z-height quality meta-data based on data derived from the plurality of images (e.g., based on the focus peak determining data set), and associates the Z-height quality meta-data with the corresponding Z-heights. The Z-height quality meta-data are usable to establish weighting factors that are used in association with the corresponding best focus Z-heights in subsequent operations that fit a workpiece surface representation to a plurality of the best focus Z-heights.

Abstract: A refined autofocus method provides optimized lighting between iterative autofocus operations, to reliably provide the best possible autofocus Z-height precision. The method includes a quantitative initial focus Z-height determination based on initial focus curve data from initial autofocus images acquired using initial light control parameters. Then, the camera is set at that initial focus Z-height such that well focused images are provided. Refined (optimized) light control parameters are then determined based on at least one respective image acquired using respective light control parameters at that Z-height, such that an image acquired using the refined light control parameters provides a near-optimum value for a contrast-related metric (e.g., a focus metric) at that Z-height. Then, refined autofocus images are acquired using the refined light control parameters and a refined precise Z-height is quantitatively determined base on the resulting focus curve.