Photon Dynamics, Inc.

Jeffrey A Hawthorne

Reza Safaee-Rad

Ray Leerentveld

Aleksander Crnatovic

Joseph Setzer

Peter J Fiekowsky

David L Baldwin

Thanh Dang

Alexander J Nagy

William K Pratt

Branko Bukal

Sunil S Sawkar

Jeffrey P Sample

Robert E Cummins

Daniel H Scott

A method and apparatus for optically inspecting a display employs sub-pixel accuracy for each primary color to take into account angle of rotation. The method includes capturing images of a display with R&#xd7;S sensors; determining sets of sensor coordinates mapping to a pixel, determining multiple misalignment angles between the pixel on the display and the R&#xd7;S sensors, determining multiple x scaling ratios, determining multiple weighting factors associated with R&#xd7;S sensors in response to the corresponding multiple misalignment angle and the corresponding multiple x and y scaling ratios, determining multiple luminance values for R&#xd7;S sensors, determining multiple total luminance values in response to the weighting factors and the luminance values, forming scaled images including first and second luminance values, and inspecting the scaled image to identify potential defects of the pixel on the display.

Method and apparatus for optical inspection of a display

A method for inspecting a display panel includes capturing images of a portion of a plurality of display panels having display elements with an image acquisition device having sensor elements, each image comprising an image of approximately a first number of display elements captured with approximately a second number of sensor elements, the first number different from the second number, each image including a Moir&#xe9; artifact pattern, combining the images of the portion of the plurality of display panels to form a reference image including a Moir&#xe9; artifact pattern reference, capturing a sample image of a portion of a sample display panel having display elements with the image acquisition device, the sample image comprising an image of approximately the first number of display elements on the sample display captured with approximately the second number of sensor elements, the sample image including a sample Moir&#xe9; artifact pattern, combining the sample image with the reference image to inhibit the sample Moir&#xe9; artifact pattern from the sample image, and to form a test image, determining defects in display elements in the portion of the sample display panel by inspecting the test image, and determining whether to reject the sample display panel in response to the defects in the display elements.

Moir&#xe9; suppression method and apparatus

Methods, apparatuses, and systems are presented for positioning a sensing head relative to a workpiece, involving a control unit operative to provide a plurality of control signals to iteratively control positioning of the sensing head relative to the workpiece, a plurality of air injectors disposed and fixedly connected on a periphery of the sensing head, each of the air injectors capable of being independently controlled to eject a gas between the sensing head and the workpiece to create an air bearing and affect positioning of the sensing head relative to the workpiece in response to at least one of the control signals, and a plurality of sensors providing a plurality of feedback signals to the control unit, the feedback signals containing information relating to positioning of an optical imaging sensing head relative to the workpiece.

Sensing head positioning system using two-stage offset air bearings

A method and apparatus for identifying and classifying pixel defects, and in particular Mura defects using digital processing techniques. The present method includes steps of acquiring an image with a Mura defect, and performing a Laplacian convolution on the image to enhance the Mura defect against background illumination. A step of thresholding the Mura defect against the background illumination is also provided. The thresholded Mura defect is compared against the original Mura defect to define statistical parameters of the original Mura defect. An annular region is defined around the periphery of the Mura defect. Statistics of the annular region defines statistics for background illumination as compared to the original Mura defect. The statistics from the Mura defect are then compared to the background illumination statistics for Mura defect classification and analysis.

Mura detection apparatus and method

An improved testing system and method for testing a flat-panel display is disclosed herein. A display is positioned under a high resolution camera for detection of, for example, brightness uniformity across the display. Errors in the detected image due to aliasing are avoided in the present invention by incrementally shifting the displayed image relative to the camera and detecting the displayed image at various shifted positions. A resulting accurate display can then be reconstructed by identifying those detector pixels generating a maximum signal. A single image may then be reconstructed using only those detected maximum pixel signals. The reconstructed image will be free of aliasing. The reconstructed image may then be analyzed electronically, and any anomalies in the pixels forming the display panel can then be accurately detected. Anomalies due to uneven brightness across the display can be corrected by programming a memory chip for the particular display panel to permanently compensate the display driver signals for each display pixel to eliminate such anomalies in the display. Other tests for viewing angles and chromaticity may also be performed.

Flat panel display inspection system

A method for inspecting a substrate having a plurality of output pixels using an image sensing device having a plurality of input pixels includes the steps of capturing an input image of a plurality of groups of output pixels with a plurality of groups of input pixels, each group of input pixels capturing a group of output pixels, each input pixel in a group of input pixels having a position, inhibiting modulation contributions from input pixels in the input image, forming a plurality of images from the plurality of groups of input pixels in the input image, each image including input pixels from a similar position in each group of input pixels, detecting defects in each of the plurality of images, and determining defects in sub-pixels of the substrate in response to the defects detected in each of the plurality of images.

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San Francisco, CA, United States of America

Jeffrey A Hawthorne