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An unassembled simple matrix liquid crystal display (LCD) panel, with strips of highly-conductive material, is tested by extracting a two-dimensional image of the capacitance distribution across the surface of the panel under test (PUT) through illumination of a modulator placed adjacent the surface, such as an NCAP modulator or other liquid dispersed polymer-based device. The light modulator is disposed to allow longitudinal probing geometries such that a measurement of capacitance is developed across a gap between the surface of the panel under test and the opposing face of the modulator which causes a power modulation in the optical energy which can be observed through an area optical sensor (such as a camera) for use in directly produce a two-dimensional spatially-dependent power modulation image directly representative of the spatially corresponding capacitance state on the surface of the panel under test.

Circuit panels, such as LCD panels, are inspected in-process and after final assembly to identify defects. Prior to final assembly, panels identified as having sufficiently few defects are repaired. Similarly after final assembly, panels identified as having sufficiently few defects are repaired. The inspection and repair systems are linked through a repair file. The inspection system identifies each defect by type and location and includes such information in the repair file. The repair system accesses such file and follows a prescribed repair method for a given type of defect at the location of such defect. Simple matrix panel defects include open line defects and line to line shorts. The inspection system includes an automated non-contact capacitance imaging system. The repair system may include a pair of lasers and a film dispenser. A first laser is used to selectively remove material and cut lines. The dispenser is for applying a liquid organic metallic film in the defect area. The second laser is for tracing a line in the film to form a conductive path repairing the defect.

A hierarchical testing method is implemented taking advantage of the nature of the most common defects in an LCD panel to achieve fast effective parametric testing of LCD panels and the like. At the first hierarchy of testing, the panel is logically divided into zones and each zone tested in isolation to identify zones having at least one defect. At the next hierarchy, electro-optic assisted zone inspection is performed to identify where within the zone the defects are located. Lastly, every pixel is inspected using a voltage imaging method to determine whether the switching integrity of the pixel is acceptable. The testing apparatus includes a plurality of panel interface devices coupling the panel under test's drive lines and gate lines to a precision measurement unit (PMU). A controller determines the PMU signals and configures the panel interface devices. The PMU monitors select drive lines and gate lines to isolate zones having defects. An electro-optic voltage measurement system is used to identify the location of defects within an isolated zone.

A hierarchical testing method is implemented taking advantage of the nature of the most common defects in an LCD panel to achieve fast effective parametric testing of LCD panels and the like. At the first hierarchy of testing, the panel is logically divided into zones and each zone tested in isolation to identify zones having at least one defect. At the next hierarchy, electro-optic assisted zone inspection is performed to identify where within the zone the defects are located. Lastly, every pixel is inspected using a voltage imaging method to determine whether the switching integrity of the pixel is acceptable. The testing apparatus includes a plurality of panel interface devices coupling the panel under test's drive lines and gate lines to a precision measurement unit (PMU). A controller determines the PMU signals and configures the panel interface devices. The PMU monitors select drive lines and gate lines to isolate zones having defects. An electro-optic voltage measurement system is used to identify the location of defects within an isolated zone.