Aplogy for not being explicit in my explanation or if I confused you. I never downgraded, I rather upgraded from IOS 6 to 6.1.3. what I meant was that I tried revert to previous version but couldnot do so that either.
Unfortunately, The suggestion doesnt helps either as its not a accesibilility Invert Colors option, rather its a screen refresh kind of issue. The impressions of previous image/screen are visible on the next picture/screen when I scroll. its like a bookmark impressions from previous image coming on top of the next image and eventually making it completely x-ray like after a while when I do a continuos scrolling.
Also, this problem had come once when I first upgraded to IOS 6 but it got resolved after booting my iphone in RESET mode by presing HOME button & the SLEEP/WAKE button. After I upgraded wit IOS patch 6.1.3, the problem reoccured and the RESET trick didnt work anymore .. .