Testing method for imaging defects in a liquid crystal display substrate

Claim 1

A method for testing imaging defects in a liquid crystal display substrate, said liquid crystal display substrate comprising a plurality of pixels, said method comprising the steps of: applying an electric impulse signal between said pixels and an electro-optical element; recording the responses of said electro-optical element with a plurality of recording means in synchronization with said application of electric signal to provide a frame data recording; storing said recording in a memory device; varying the magnitude and polarity of said electric signal and applying the changed signal between said pixels and said electro-optical element; recording the responses of said array to said changes in changed signal to produce further frame data and storing said recording of further frame data; repeating the above steps to provide a plurality of frame data recordings; recalling said recordings frame at a time from memory; subjecting said frame data to image analysis processing whereby defective pixels are identified from the response characteristics of said electro-optical element to changes in the applied signal.

Claim 2

A method for testing imaging defects in a liquid crystal display substrate, said liquid crystal display substrate comprising a plurality of pixels, said method comprising the steps of: applying an electric impulse signal between said pixels and an electro-optical element; recording the responses of said electro-optical element with a plurality of recording means in synchronization with said application of electric signal to provide a frame data recording; storing said recording in a memory device; varying the magnitude and polarity of said electric signal and applying the changed signal between said pixels and said electro-optical element; recording the responses of said array to said changes in changed signal to produce further frame data and storing said recording of further frame data; repeating the above steps to provide a plurality of frame data recordings; recalling said recordings frame at a time from memory; subjecting said frame data to image analysis processing whereby defective pixels are identified from the response characteristics of said electro-optical element to changes in the applied signal.

Claim 8

A method for testing liquid crystal display substrate comprising the steps of: employing an electro-optical element having a first and second side, said first side of said electro-optical element being coated with a transparent conductive layer, said second side of said electro-optical element being coated with a non-conductive, reflective material, said electro-optical element appearing non-transparent in the absence of an electric field across it; employing a liquid crystal display substrate to be tested having first and second sides, said first side having a plurality of gate, source, and drain lines, and pixel elements; placing said element-optical directly over, and immediately adjacent to said liquid crystal display substrate, such that the second side of said electro-optical element is facing, and slightly separated from said first side of said liquid crystal display substrate; connecting a first terminal of a voltage source to said transparent conductive layer on said first side of said electro-optical element, connecting a second terminal of said voltage source to said source lines and connecting a third terminal of said voltage source to said drain lines formed on said liquid crystal display substrate, said first terminal servicing as a common reference voltage, said second and third terminals being independently controllable; irradiating a beam of light from above said electro-optical element, such that said beam of light irradiates said first side of said electro-optical element; applying a voltage between said transparent conductive element on said first side of said electro-optical element, and said gate and/or source lines on said liquid crystal display substrate, such that a voltage difference is generated between the two which is of sufficient magnitude to create an electric field between said pixel elements and said transparent conductive element to cause said electro-optical element to appear transparent to said a radiated beam of light; measuring the intensity of the light reflected off of said second side of said electro-optical element, such that a defective portion of said liquid crystal display substrate which fails to apply the voltage to pixel elements therein is detected; utilizing a plurality of light detection apparatuses to detect the light reflected from said second surface of said electro-optical element; and merging the results observed by each of said light detection apparatuses to form a single electronic image representing the functioning and non-functional pixels of said liquid crystal display substrate.

Claim 9

A method for testing liquid crystal display substrate comprising the steps of: employing an electro-optical element having a first and second side, said first side of said electro-optical element being coated with a transparent conductive layer, said second side of said electro-optical element being coated with a non-conductive, reflective material, said electro-optical element appearing non-transparent in the absence of an electric field across it; employing a liquid crystal display substrate to be tested having first and second sides, said first side having a plurality of gate, source, and drain lines, and pixel elements; placing said element-optical directly over, and immediately adjacent to said liquid crystal display substrate, such that the second side of said electro-optical element is facing, and slightly separated from said first side of said liquid crystal display substrate; connecting a first terminal of a voltage source to said transparent conductive layer on said first side of said electro-optical element, connecting a second terminal of said voltage source to said source lines and connecting a third terminal of said voltage source to said drain lines formed on said liquid crystal display substrate, said first terminal servicing as a common reference voltage, said second and third terminals being independently controllable; irradiating a beam of light from above said electro-optical element, such that said beam of light irradiates said first side of said electro-optical element; applying a voltage between said transparent conductive element on said first side of said electro-optical element, and said gate and/or source lines on said liquid crystal display substrate, such that a voltage difference is generated between the two which is of sufficient magnitude to create an electric field between said pixel elements and said transparent conductive element to cause said electro-optical element to appear transparent to said a radiated beam of light; measuring the intensity of the light reflected off of said second side of said electro-optical element, such that a defective portion of said liquid crystal display substrate which fails to apply the voltage to pixel elements therein is detected; utilizing a plurality of light detection apparatuses to detect the light reflected from said second surface of said electro-optical element; and merging the results observed by each of said light detection apparatuses to form a single electronic image representing the functioning and non-functional pixels of said liquid crystal display substrate.

Claim 16

A method for testing liquid crystal display substrate comprising the steps of: employing a liquid crystal display substrate having first and second sides, said first side having a plurality of conductive lines and pixel elements; placing an electro-optical element directly over, and immediately adjacent to said liquid crystal display substrate, such that a first, reflective side of said electro-optical element is facing, and slightly separated from said first side of said liquid crystal display substrate, said electro-optical element being essentially non-transparent when an electric field is not applied across it; connecting a voltage source to an optically transparent electrode on a second side of said electro-optical element, and said conductive lines formed on said liquid crystal display substrate; applying a beam of light from above said electro-optical element, such that said beam of light radiates said second side of said electro-optical element; applying a voltage between said second side of said electro-optical element, and said conductive lines on said liquid crystal display substrate, such that a voltage difference is generated between the two which is of sufficient magnitude to generate an electric field, and cause said electro-optical element to become transparent to said a radiated beam of light; measuring the light reflected off of said reflective side of said electro-optical element, such that a defective portion of said liquid crystal display substrate which fails to apply the voltage level to pixel elements therein is detected; utilizing a plurality of light detection apparatuses to detect the light reflected from said reflective side of said electro-optical element; and merging the results observed by each of said light detection apparatuses to form a single electronic image displaying functional and non-functional sections of said liquid crystal display substrate.

Claim 17

A method for testing liquid crystal display substrate comprising the steps of: employing a liquid crystal display substrate having first and second sides, said first side having a plurality of conductive lines and pixel elements; placing an electro-optical element directly over, and immediately adjacent to said liquid crystal display substrate, such that a first, reflective side of said electro-optical element is facing, and slightly separated from said first side of said liquid crystal display substrate, said electro-optical element being essentially non-transparent when an electric field is not applied across it; connecting a voltage source to an optically transparent electrode on a second side of said electro-optical element, and said conductive lines formed on said liquid crystal display substrate; applying a beam of light from above said electro-optical element, such that said beam of light radiates said second side of said electro-optical element; applying a voltage between said second side of said electro-optical element, and said conductive lines on said liquid crystal display substrate, such that a voltage difference is generated between the two which is of sufficient magnitude to generate an electric field, and cause said electro-optical element to become transparent to said a radiated beam of light; measuring the light reflected off of said reflective side of said electro-optical element, such that a defective portion of said liquid crystal display substrate which fails to apply the voltage level to pixel elements therein is detected; utilizing a plurality of light detection apparatuses to detect the light reflected from said reflective side of said electro-optical element; and merging the results observed by each of said light detection apparatuses to form a single electronic image displaying functional and non-functional sections of said liquid crystal display substrate.