Glass sheet acquisition and positioning system and associated method for an inline system for measuring the optical characteristics of a glass sheet

An inline apparatus for measuring the optical characteristics of a glass sheet in a system for fabricating glass sheets including one or more processing stations and one or more conveyors for conveying the glass sheet from station to station during processing, the apparatus comprising:

• a background screen including contrasting elements arranged in a pre-defined pattern,
• a digital camera for acquiring an image of the background screen,
• a glass sheet acquisition and positioning mechanism for receiving a glass sheet as it is conveyed on one of the conveyors, momentarily removing the glass sheet from the conveyor, and positioning the glass sheet in the path between the camera and the background screen so that the camera may capture an image of the pattern transmitted through the glass sheet, the acquisition and positioning mechanism including:
• an exterior support frame mounted in proximity to the conveyor between the camera and the background screen;
• and
• a moveable glass sheet support frame operably connected to the exterior support frame such that the glass sheet support frame may be selectively positioned from a first generally horizontal orientation in the plane of the glass sheet on the conveyor to a second, upwardly-tilted orientation whereby the glass sheet support frame is elevated from the plane of the conveyor with a glass sheet retained thereon to thereby position the glass sheet between the camera and the screen at the preselected position, and thereafter re-positioned for releasing the glass sheet from the glass sheet support frame for continued movement on the conveyor;
• and
• a computer including at least one processor programmed to execute logic for receiving the captured image data associated with a selected glass sheet and performing one or more processing operations using the captured image data to analyze the optical characteristics of the glass sheet.

An inline apparatus for measuring the optical characteristics of a glass sheet in a system for fabricating glass sheets including a heating station for heating the glass sheet to a temperature adequate to soften the glass for forming into a desired shape, a bending station wherein the softened sheet is formed to the desired shape, a cooling station wherein the formed glass sheet is cooled in a controlled manner, and one or more conveyors for conveying the glass sheet from station to station during processing, the apparatus including:

• a background screen including contrasting elements arranged in a pre-defined pattern;
• a camera for acquiring an image of the background screen;
• a glass sheet part identifier including a sensor for acquiring data associated with the shape of a glass sheet travelling on a conveyor upstream from the background screen;
• a glass sheet acquisition and positioning mechanism including a programmable control including logic for controlling the mechanism based upon the shape data acquired by the part identifier to receive the glass sheet as it is conveyed on one of the conveyors, momentarily remove the glass sheet from the conveyor, and position the glass sheet in the path between the camera and the background screen so that the camera may capture an image of the pattern transmitted through the glass sheet;
• and
• a computer including logic for receiving the captured image data associated with a selected glass sheet and performing one or more processing operations using the captured image data to analyze the optical characteristics of the glass sheet.

A method for measuring the optical characteristics of a glass sheet as the glass sheet is conveyed in a system for fabricating glass sheets including one or more processing stations and one or more conveyors for conveying the glass sheet from station to station during processing, the method including at least the steps of

• providing a background screen including contrasting elements arranged in a pre-defined pattern and a camera for acquiring an image of the background screen;
• acquiring data associated with the shape of a glass sheet travelling on a conveyor upstream from the background screen;
• capturing a glass sheet at a preselected location as it is transported on the conveyor;
• removing the glass sheet from the conveyor;
• and
• positioning the glass sheet between the camera and the screen in a preselected orientation and thereafter acquiring an image of the background screen;
• re-positioning the glass sheet for continued movement of the glass sheet on the conveyor;
• and
• performing one or more processing operations using the acquired image data to analyze the optical characteristics of the glass sheet.