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					<a href="http://www.hdtv.ru/">HDTV.ru</a> > Новости индустрии > <a href="http://www.hdtv.ru/news/industry/13129-led-podsvetka-i-golovnaya-bol.html">LED подсветка и головная боль</a>
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					<h1>LED подсветка и головная боль</h1>
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					<small>21.03.2013</small>
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<div align="center"><!--dle_image_begin:http://www.hdtv.ru/uploads/posts/2013-03/1363842739_led.jpg|--><img src="http://www.hdtv.ru/uploads/posts/2013-03/1363842739_led.jpg" alt="LED подсветка и головная боль" title="LED подсветка и головная боль"  /><!--dle_image_end--></div><br /><br />Широко используемая сегодня светодиодная (LED) подсветка для ЖК дисплеев может привести к усталости и головной боли. А причиной является, казалось бы, уже давно забытый эффект мерцания. Правда проявляется он не во всех режимах и благодаря экономии некоторых производителей на системе регулирования яркости подсветки.  Дисплей может обладать незаметным эффектом мерцания, особенно если он обладает чрезмерно высокой яркостью, которую приходится серьезно уменьшать.<br /><br /><div align="center"><!--TBegin--><a href="http://www.hdtv.ru/uploads/posts/2013-03/1363842784_led2.jpg" onclick="return hs.expand(this)" ><img src="http://www.hdtv.ru/uploads/posts/2013-03/thumbs/1363842784_led2.jpg" alt='LED подсветка и головная боль' title='LED подсветка и головная боль'  /></a><p class="thumb_enlarge"><img src="/engine/skins/images/enlarge.png" width="16" height="16" border="0">Кликните на картинку для ее увеличения</p><!--TEnd--></div><br /><br />Причина в том, что для регулировки яркости светодиодов используется (особенно в дешевых мониторах) метод широтно-импульсной модуляции (ШИМ). Чем выше яркость, тем длительнее периоды горения светодиодов, вплоть до постоянного горения на максимальной яркости. А многим монитора достаточно сегодня 20-30 % яркости. Альтернативой методу ШИМ является использовавшийся для регулировки яркости CCFL подсветки метод изменения уровня подаваемого напряжения (пила на рис. слева).<br /><br /><div align="center"><!--dle_image_begin:http://www.hdtv.ru/uploads/posts/2013-03/1363842808_led3.jpg|--><img src="http://www.hdtv.ru/uploads/posts/2013-03/1363842808_led3.jpg" alt="LED подсветка и головная боль" title="LED подсветка и головная боль"  /><!--dle_image_end--></div><br /><br />Бороться с эффектом мерцания ШИМ метода помогает и увеличение исходной частоты импульсов регулировки яркости подсветки.
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