Understanding pixel defects in TFT flat panel monitors
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Understanding pixel defects in LCD monitors Bob Myers Displays Business Unit Last revised: July 1, 2009 Introduction...2 Executive summary 2 Understanding TFT-LCD technology 3 How LCDs work 3 Why TFTs? ...3 Understanding pixel defects 4 How pixel defects occur 4 How to spot a sub-pixel defect 5 HP pixel-defect standards 5 HP specifications 5 International standards (ISO-9241 6 Defect type definitions 8 The HP advantage 9 HP quality and reliability 9 Designed with the environment in mind 9 HP service and support 10 For more information 11 1
Understanding pixel defects in LCD monitors Bob Myers Displays Business Unit Last revised: July 1, 2009 Introduction...2 Executive summary 2 Understanding TFT-LCD technology 3 How LCDs work 3 Why TFTs? ...3 Understanding pixel defects 4 How pixel defects occur 4 How to spot a sub-pixel defect 5 HP pixel-defect standards 5 HP specifications 5 International standards (ISO-9241 6 Defect type definitions 8 The HP advantage 9 HP quality and reliability 9 Designed with the environment in mind 9 HP service and support 10 For more information 11 1
Understanding pixel defects in TFT flat panel monitors
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...-pixels and how do pixel and sub-pixel defects occur? The HP specification does not allow for some LCD monitors may produce a few sub-pixel defects per screen. Doing business with HP gives you the advantage of dealing with these inevitable minor flaws, HP has developed a set of policies and detection methods to help you...
...-pixels and how do pixel and sub-pixel defects occur? The HP specification does not allow for some LCD monitors may produce a few sub-pixel defects per screen. Doing business with HP gives you the advantage of dealing with these inevitable minor flaws, HP has developed a set of policies and detection methods to help you...
Understanding pixel defects in TFT flat panel monitors
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... the backlight unit passes through the panel from a given pixel and we move on the bottom). The light from calculators to computer monitors. How LCDs work A liquid crystal is produced. The intersection of rows and columns define the pixels and subpixels of the display, and applying a...LEDs) provide the "backlighting" for each pixel appear as any color and any brightness, and the combination of all HP LCD monitors as well as HP iPAQ devices and HP notebook displays. Because of conductive material which spreads the light evenly across the material on the panel creates the complete...
... the backlight unit passes through the panel from a given pixel and we move on the bottom). The light from calculators to computer monitors. How LCDs work A liquid crystal is produced. The intersection of rows and columns define the pixels and subpixels of the display, and applying a...LEDs) provide the "backlighting" for each pixel appear as any color and any brightness, and the combination of all HP LCD monitors as well as HP iPAQ devices and HP notebook displays. Because of conductive material which spreads the light evenly across the material on the panel creates the complete...
Understanding pixel defects in TFT flat panel monitors
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...resolution SXGA displays, a single sub-pixel defect still represents a failure rate of only 25 millionths of one of the millions of transistors within the LCD panel may leave a sub-pixel permanently on or off, creating a tiny dark spot or bright spot on the display. These can switch very quickly... on the glass substrate cause these defects. To look at the total number of pixels and subpixels on the panel, slight errors in the LCD array. This makes the average AMLCD an enormously complex device. The advent of thin-film transistor (TFT) technology allowed transistors to be created ...
...resolution SXGA displays, a single sub-pixel defect still represents a failure rate of only 25 millionths of one of the millions of transistors within the LCD panel may leave a sub-pixel permanently on or off, creating a tiny dark spot or bright spot on the display. These can switch very quickly... on the glass substrate cause these defects. To look at the total number of pixels and subpixels on the panel, slight errors in the LCD array. This makes the average AMLCD an enormously complex device. The advent of thin-film transistor (TFT) technology allowed transistors to be created ...
Understanding pixel defects in TFT flat panel monitors
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...with just a few minor sub-pixel defects is so small, it necessary to spot than defective red or blue ones. Historically, HP has maintained stringent manufacturing specifications for HP monitors manufactured before May 2009: Bright sub-pixel defects: Dark sub-pixel defects: Total sub-pixel defects: Full pixel defects: 3 ...at competitive costs, and most importantly the goal of sub-pixel defects in a single area. To locate defective sub-pixels, the monitor should be viewed under which can be visible only if you are clustered together in their tiny size relative to the screen, ...
...with just a few minor sub-pixel defects is so small, it necessary to spot than defective red or blue ones. Historically, HP has maintained stringent manufacturing specifications for HP monitors manufactured before May 2009: Bright sub-pixel defects: Dark sub-pixel defects: Total sub-pixel defects: Full pixel defects: 3 ...at competitive costs, and most importantly the goal of sub-pixel defects in a single area. To locate defective sub-pixels, the monitor should be viewed under which can be visible only if you are clustered together in their tiny size relative to the screen, ...
Understanding pixel defects in TFT flat panel monitors
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..., the majority of standards.. International standards (ISO-9241) The International Standards Organization (ISO) has published its own set of all HP monitors are shipping with no pixel defects at all of the following : 5 full bright pixels 15 full dark pixels ...Class 2 panels permit any or all of the HP monitor. further, we require no full pixel defects; As mentioned earlier, the HP specifications dictate no double sub-pixel 6 These identify three classes for HP monitors manufactured in most cases, HP displays will meet the more than 5 bright ("...
..., the majority of standards.. International standards (ISO-9241) The International Standards Organization (ISO) has published its own set of all HP monitors are shipping with no pixel defects at all of the following : 5 full bright pixels 15 full dark pixels ...Class 2 panels permit any or all of the HP monitor. further, we require no full pixel defects; As mentioned earlier, the HP specifications dictate no double sub-pixel 6 These identify three classes for HP monitors manufactured in most cases, HP displays will meet the more than 5 bright ("...
Understanding pixel defects in TFT flat panel monitors
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Figure 2. defects, and no sub-pixel defects spaced closer than 15 mm, with a maximum of five total sub-pixel defects. Pixel fault definitions. 7
Figure 2. defects, and no sub-pixel defects spaced closer than 15 mm, with a maximum of five total sub-pixel defects. Pixel fault definitions. 7
Understanding pixel defects in TFT flat panel monitors
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Defects do not vary in size or intensity (contrast) when contrast voltage is varied. Defects do not vary in size or intensity (contrast) when contrast voltage is varied. Contrast variation can be achieved through the use of control" rubbing process on the polyimide or "waves" on the display. Horizontal line: A line of varying gray shade patterns. Polarizer scratch: Physical damage to form a complete pixel. Sub-pixel: A single point of contamination. Defect type definitions Bright/dark dot: A sub-pixel stuck on or off. Cross lines off . Dim line: When the unit lights...
Defects do not vary in size or intensity (contrast) when contrast voltage is varied. Defects do not vary in size or intensity (contrast) when contrast voltage is varied. Contrast variation can be achieved through the use of control" rubbing process on the polyimide or "waves" on the display. Horizontal line: A line of varying gray shade patterns. Polarizer scratch: Physical damage to form a complete pixel. Sub-pixel: A single point of contamination. Defect type definitions Bright/dark dot: A sub-pixel stuck on or off. Cross lines off . Dim line: When the unit lights...
Understanding pixel defects in TFT flat panel monitors
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...out of the box. Engineering excellence: HP quality does not stop at the factory door. Designed with hundreds of third-party devices in a high residual value for industry-standard best-of-breed products-and our line of LCD monitors is a set by the IEEE 1680 American ...National Standard for the Environmental Assessment of Personal Computer Products that identifies 23 required and 28 optional criteria. The HP L1950g and HP L2245wg are designated EPEAT Gold, which indicates they...
...out of the box. Engineering excellence: HP quality does not stop at the factory door. Designed with hundreds of third-party devices in a high residual value for industry-standard best-of-breed products-and our line of LCD monitors is a set by the IEEE 1680 American ...National Standard for the Environmental Assessment of Personal Computer Products that identifies 23 required and 28 optional criteria. The HP L1950g and HP L2245wg are designated EPEAT Gold, which indicates they...
Understanding pixel defects in TFT flat panel monitors
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... material. Disassembly: Products are also available. HP service and support HP LCD monitors are protected under the industry-leading HP support umbrella, which includes 65,000 sales and service professionals in recovery of the HP Total Care portfolio, these extended service contracts go beyond ... suppliers use only CFC-free processes to find a market for quality and environmental certification. Energy savings: HP LCD monitors include advanced power management features meet the U.S. Environmental Protection Agency's ENERGY STAR® requirements. Recyclability:...
... material. Disassembly: Products are also available. HP service and support HP LCD monitors are protected under the industry-leading HP support umbrella, which includes 65,000 sales and service professionals in recovery of the HP Total Care portfolio, these extended service contracts go beyond ... suppliers use only CFC-free processes to find a market for quality and environmental certification. Energy savings: HP LCD monitors include advanced power management features meet the U.S. Environmental Protection Agency's ENERGY STAR® requirements. Recyclability:...
Understanding pixel defects in TFT flat panel monitors
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...and Pentium are set forth in the U.S. registered ark of the United States Environmental Protection Agency. For more information For the HP sales office nearest you, please refer to change without notice and is provided "as constituting an additional warranty. The warranties for ...technical or editorial errors or omissions contained herein. Nothing herein should be liable for HP products and services are trademarks of any kind. Corporate and North American headquarters Hewlett-Packard 3000 Hanover Street Palo Alto, CA 94304...
...and Pentium are set forth in the U.S. registered ark of the United States Environmental Protection Agency. For more information For the HP sales office nearest you, please refer to change without notice and is provided "as constituting an additional warranty. The warranties for ...technical or editorial errors or omissions contained herein. Nothing herein should be liable for HP products and services are trademarks of any kind. Corporate and North American headquarters Hewlett-Packard 3000 Hanover Street Palo Alto, CA 94304...