Above the HD Guru demonstrates “LCD screen flashing” when he lightly taps the on latest Sony large screen LCD at the CEDIA show in Denver. The tapping causes the LCD screen to produce a momentary burst of white rays in a circular pattern from the point of where the finger contacts the screen. This phenomena occurs due to a temporary misalignment of the crystals within the panel, allowing the back light to shine through.
There is no permanent damage to the TV. Of course, damage (in the form of destroying your LCD panel) will occur if one was to poke at the panel with enough force to break the glass within the panel, instead of lightly tapping on it. The HD Guru takes no responsibility for any damage to any LCD TV if anyone dares to try this themselves. By the way, the effect also occurs on (large screen) Sharp, Samsung as well as other model Sony panels, but not on panels made by LG and some other LCD makers and is most noticeable when the image on the screen is dark.
Copyright ©2007 Gary Merson/HD Guru™. All rights reserved. The content and photos within may not be distributed electronically or copied mechanically without specific written permission.
Why does it matter… Wait until JorgeX needs service on his Vizo after the warrenty period is up. Check out that article!
Gary, why does this matter?
I don’t like LCDs, but this is splitting hairs.
Who taps on their display while watching TV?
Ha ha ha. JorgieX bought a Vizio.
Three cheers for future products with yesterday’s specs!
I don’t ever get anything like that when I tap or clean my 47″ FULL 1080p Vizio.
uh.. ok… have you ever had an lcd computer display??? how about a laptop ?
I’ve got an Apple 20″ LCD display and the effect doesn’t occur. Don’t know about my 42″ Samsung.. haven’t touched the screen.
I think this goes to show that LCD screens are not very kiddies friendly…
The “tapping of the screen” was not deliberate [as you say - "stupid and pointless"] – it was only noticeable when I (and other perhaps) took the time to CLEAN the screen, or move the display around (mine was a computer montior/HDTV unit).
You might touch the screen a little when doing either of the above, and BAM – you noticed the same effect that HDGuru did in his post above.
See, it was only THEN that I noticed the effect. But I don’t know what prompted HDGuru to touch the larger screen display; perhaps he was curious about the newer Sony/Samsung glass that’s in these new units.
And what is the point of demonstrating this? Why would you want to tap on your screen? This is something stupid to do, very pointless.
Hi HDGuru…
Yeah, I noticed this back in summer 2005 when I purchased a Sony 17-inch, 720p LCD HDTV/computer monitor [with DVI/Component/S video/composite inputs, NTSC tuner, and PIP also] – model MFM-HT75W.
I thought it looked weird initially, but it’s really no big deal, as after tapping the screen the effect quickly disappears, with no apparent wear to the screen’s HD image quality.
I knew it had something to do with the special glass used for this unit, but did not realize until your new post today that the same effect is seen on the regular LCD glass for Sony HDTVs (and the other mentioned brands).