@manoj48799 first connect an external monitor. Let us know what that displays. If that displays properly you know the issue is your LCD, display cable or display connector.
Next download the Maintenance and Service guide for your computer [http://h10032.www1.hp.com/ctg/Manual/c02666747.pdf|from here] Page 73 of that manual will tell you how to replace it and what the proper part number is. While you work on the laptop, check the cable for bend connectors, broken or torn insulation etc, and check your connector properly for corrosion and shorted components around the connector.
If in doubt, you can always post some pictures of what you find, with your Question. That way we can see what you see and hopefully help you out more.
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