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This is a copy and paste from a HDTV guide I wrote a while back
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The human eye is capable of retaining the presence of light even after the source has faded/moved away from the line of sight. It is the sole reason we perceive motion blur in the real world. The problem lies within our eyes retina, which fails to dissipate the perceived light at the desired rate. Also, increased intensity and prolonged exposure leads to increased latency in decay. To complicate matters, not all individuals perceive light in the same manner, which is why some react to motion differently compared to others. Cameras on the other hand are immune to such effects thanks to the variable shutter speed and exposure. Too bad we humans lack such imperative features.
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Virtually all LCDs are based on the driving mechanism known as [Active Matrix] (AM), which addresses the pixels (in a row) line by line from top to bottom. The active elements (pixels) maintain their value for a set period of time, which is known as hold-time. At 60Hz, each frame containing unique information is held and updated every 16.7ms. Hold-type blur occurs when the retina is tracking a moving object on a frame based display. Such displays can only display discrete still images while our eyes move in a continuous analogue fashion. This creates a conflict when watching motion video because the eye is continuously moving (tracking the moving object) even though each frame is stationary on the screen. Due to retinal persistence, the still frame will draw a blur onto the viewers moving retina.
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Due to the nature of AM-LCD, only the new segments are updated while leaving the rest untouched. For example, if one were to display a red bouncing ball in a blue background, only the pixels displaying the red ball are addressed. The rest remain unaltered, which prolongs the retention even further.
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To combat this problem, several manufacturers have developed and implemented a picture processing technique known as High-Level MCFI/MVFI (100-240Hz), which synthesizes new frames from existing frames to reduce the hold-time thus reducing the perception of motion blur of high-motion contents (50/60i/p). But the technology is far from perfect and it often causes image and motion artifacts that can be quite distracting.
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PDPs do not suffer as much from such phenomenon because the hold- time is significantly shorter than LCD due to the use of driving mechanism known as Pulse Width Modulation (PWM). During the 0-16.7ms (60Hz) time frame, the PWM creates series of pulses that over time assemble itself as a single image [illustrative version]. Compiling an image in this manner means that every frame will begin as black and as each successive pulse is added, the image becomes brighter and brighter until the final full image is realized. The panel then resets to black and begins to compile a new frame. Of the 16.7ms it takes to compile a frame, only about 4-8ms (at the end of each frame time) of that time is high luminance. In this manner, we perceive an effective hold-time of ~4-8ms which is significantly shorter than the full 16.7ms hold time of LCD. This is also the source of perceived flicker in PDP.
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The human eye is capable of retaining the presence of light even after the source has faded/moved away from the line of sight. It is the sole reason we perceive motion blur in the real world. The problem lies within our eyes retina, which fails to dissipate the perceived light at the desired rate. Also, increased intensity and prolonged exposure leads to increased latency in decay. To complicate matters, not all individuals perceive light in the same manner, which is why some react to motion differently compared to others. Cameras on the other hand are immune to such effects thanks to the variable shutter speed and exposure. Too bad we humans lack such imperative features.
---
Virtually all LCDs are based on the driving mechanism known as [Active Matrix] (AM), which addresses the pixels (in a row) line by line from top to bottom. The active elements (pixels) maintain their value for a set period of time, which is known as hold-time. At 60Hz, each frame containing unique information is held and updated every 16.7ms. Hold-type blur occurs when the retina is tracking a moving object on a frame based display. Such displays can only display discrete still images while our eyes move in a continuous analogue fashion. This creates a conflict when watching motion video because the eye is continuously moving (tracking the moving object) even though each frame is stationary on the screen. Due to retinal persistence, the still frame will draw a blur onto the viewers moving retina.
---
Due to the nature of AM-LCD, only the new segments are updated while leaving the rest untouched. For example, if one were to display a red bouncing ball in a blue background, only the pixels displaying the red ball are addressed. The rest remain unaltered, which prolongs the retention even further.
---
To combat this problem, several manufacturers have developed and implemented a picture processing technique known as High-Level MCFI/MVFI (100-240Hz), which synthesizes new frames from existing frames to reduce the hold-time thus reducing the perception of motion blur of high-motion contents (50/60i/p). But the technology is far from perfect and it often causes image and motion artifacts that can be quite distracting.
---
PDPs do not suffer as much from such phenomenon because the hold- time is significantly shorter than LCD due to the use of driving mechanism known as Pulse Width Modulation (PWM). During the 0-16.7ms (60Hz) time frame, the PWM creates series of pulses that over time assemble itself as a single image [illustrative version]. Compiling an image in this manner means that every frame will begin as black and as each successive pulse is added, the image becomes brighter and brighter until the final full image is realized. The panel then resets to black and begins to compile a new frame. Of the 16.7ms it takes to compile a frame, only about 4-8ms (at the end of each frame time) of that time is high luminance. In this manner, we perceive an effective hold-time of ~4-8ms which is significantly shorter than the full 16.7ms hold time of LCD. This is also the source of perceived flicker in PDP.
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