Hi there and welcome to Just Answer. Thanks for asking your question.
Your Sharp is probably a 720p TV (give me the model number).
Turn the PS3 on and hold down the on/off button for 10-15 seconds. This will reset the PS3's display to 480p so you will see it on your screen.
Now go into the display setting on the PS3 and change them to 720p. There will be some other things too but that is the important one. Uncheck 1080i and 1080p.
That should fix it for you.
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