Abstract: A method and system for automatically generating reference height data for use in a 3D inspection system are provided wherein local reference areas on an object are initially determined and then the height of these local reference areas are determined to generate the reference height data. When the object is a printed circuit board, the local reference areas are located relative to predetermined interconnect sites where solder paste is to be deposited or components placed and from which the relative height of the solder paste or components is to be determined using the reference height data during the subsequent inspection process.

Abstract: A triangulation-based method and system for high speed 3D and gray scale imaging and associated pre-processing of digitized information allows for estimation or filtering of height and gray scale values based upon the confidence level of the information obtained from a pair of sensors and also based upon knowledge of the object structure and its reflectance characteristics. A modulated laser beam is scanned across the object to create a plurality of spots which are viewed by a pair of well-matched receivers. Each receiver includes a light collection and delivery system, a position sensitive detector, and an associated ratiometric signal processor, or similar means for extraction of height and intensity information or data by triangulation. An optional automatic light control sub-system provides greatly extended dynamic range with control inputs derived from an amplifying detector included in each receiver to maximize occurrences of valid data points.

Abstract: A triangulation-based method and system for high speed 3D and gray scale imaging and associated pre-processing of digitized information allows for estimation or filtering of height and gray scale values. This estimation is based upon the confidence level of the information obtained from a pair of sensors and also based upon knowledge of the object structure and its reflectance characteristics. A modulated laser beam is scanned across the object to create a plurality of spots which are viewed by a pair of well-matched receivers. Each receiver includes a light collection and delivery system, a position sensitive detector, and an associated ratio-metric signal processor, or similar means for extraction of height and intensity information or data by triangulation. An optional automatic light control sub-system provides greatly extended dynamic range with control inputs derived from an amplifying detector included in each receiver to maximize occurrences of valid data points.

Abstract: A triangulation-based method and system for high speed 3D and gray scale imaging and associated pre-processing of digitized information allows for estimation or filtering of height and gray scale values based upon the confidence level of the information obtained from a pair of sensors and also based upon knowledge of the object structure and its reflectance characteristics. A modulated laser beam is scanned across the object to create a plurality of spots which are viewed by a pair of well-matched receivers. Each receiver includes a light collection and delivery system, a position sensitive detector, and an associated ratio-metric signal processor, or similar means for extraction of height and intensity information or data by triangulation. An optional automatic light control sub-system provides greatly extended dynamic range with control inputs derived from an amplifying detector included in each receiver to maximize occurrences of valid data points.

Abstract: A method and system are disclosed for automatically visually inspecting an article such as an electronic circuit wherein both reference and non-reference algorithms are utilized to detect circuit defects. The system includes a pipelined cellular image processor which is utilized to implement the non-reference algorithm and an arithmetic logic unit (ALU) is coupled to the output of the cellular image processor to perform the reference method. The non-reference method includes a spaces and traces algorithm and the reference method includes a topology matching algorithm. The system also includes an algorithm for locating and gauging critical areas of the circuit with sub-pixel accuracy.