which parts needs to be replaced ?? Sony - KV - 20S20 TV

[niljaviya]

hi friends,
i have SONY KV- 20S20 Television
since few days the problem occurs, all colors are excellent except white color
when white color display the the green shade also appear with all out lines of white image. the green shade is really too noticeable, u can see all white color is covered by green
it only happans in white color , not in any other color
pls guide me what should i do??

thanks to all of u