Disappointed with LED LCD in E6400

I recall we concluded that the brightness of LED backlighting is controlled by turning the LEDs on and off. At the lowest brightness the off period can become long enough to be noticeable. I usually keep to one or two steps above the lowest, which is much easier on the eyes and doesn't use much more power.

John

 

Yes,

I believe John is correct. It seems the LG (and maybe samsungs too) LED screens employ Pulse Width Modulation (PWM) to decrease the brightness level. So, at full brightness, the LEDs are fed a continious voltage, lets say 5v. However, at half brightness, the LEDs are fed a pulsed signal that is either 0v (LEDs off) or 5v (LEDs on). Since your eyes retain brightness for a short period of time, the on/off timing is done in a way so your eyes perceive a certain level of brightness. I bet if you took a high speed camera to these LED panels, you could see the on off switching, especially at low brightness.

When I had my e6500, I noticed the flickering at low brightness too. I always wondered if it could trigger seizures...

 

what software I can use to check what screen I have?

 

Control Panel / Device Manager / Monitors / Generic PnP Monitor / Right Click Properties / Details / Hardware ID

No additional software required, it's all in Windows already.

 

As I mentioned above, I got a surprise True-Life from AUO (3rd largest manufacturer) on a WXGA+ E6400 from the Outlet Store. I don't notice a flicker at low light levels. Colors and contrast are good but not crazy about the reflections.

 

The True-Life RGB LED monitor is only available with the Precision M4400 in 1920x1200 or on the Studio XPS 16 in 1920x1080 resolution as far as I know.

 

I can't say for sure whether the E6400 I received from the Outlet store actually has a TrueLife LED monitor. I could not find that that anywhere in the documentation. I do know that its an AU4047 screen and it's definitely not anti-glare.

 

Mine's the LPL0140, i like the color, is much better than my samsung LCD on thinkpad. I should say expcet my IPS screen, this is is the best i have on my 4 laptops.

 

Alright, I have an e6400 with a Samsung display and another with the LG display. I took photography up as a hobby and have some pictures I was using to test which one I wanted to keep. The LG looks more natural, which I prefere so I can edit photos and have them print the same. The Samsung looks a bit more vibrant but the colors aren't as natural. The skies seem to have a bit more blue/purple in them, etc. I have a good picture of some flowers in Hawaii with a blue sky as a background that I was using as a test image. On the LG, there is more detail in the shiny spots where the sun is reflecting on them. They both seem to handle edges of objects differently. The edges of the flowers look sharper on the LG, the samsung looks like it smoothes them a bit. Both look very good and I think the colors could be toned down a bit in the Samsung in the display options so that I couldn't tell much of a difference. Both computers have the nvidia card. I swapped the screens and saw the same thing, so its not the computer.

 

Anyone gotten the CMO LED panel for WXGA resolution?

Was experiencing some backlight flickering/brightness 'twitching' when scrolling web pages or photo editing (while on battery) so decided to call in for a replacement.

Just got a new CMO screen to replace my current LPL, the twitching didn't go away so I guess it's something to do with LED technology. But the CMO screen has this green tint on it.

Comparing both my WXGA panels, the CMO LED isn't as bright as the LG Philips LED. My whites don't get blown as easily also (regardless of brightness level) as compared to the LG and photos have more depth to them. Wonder if CMO LED all have this green color tint, or I happen to be unlucky?