If you are using an antenna on your Sharp TV , make sure it is set right and Signal is available.Wrong or displaced position of the Antenna more usually cause [link|https://sharptvxpert.com/sharp-tv-black-screen-of-death/|Black screen on my Sharp TV.|new_window=true]
Check your TV Settings -Try to Change the Display or Picture settings if it works.
If nothing works,there are chances of possibilities that your TV Panel are faulty.Best is that you use your Sharp warranty and get it fixed if it is more critical issue.