The Samsung Galaxy Tab S 10.5 released in July 2014 is a 10.5” Android tablet with a 2560x1600 pixel resolution, 16GB of storage, and 8.0MP camera.
Model numbers: SM-T800 (WIFI), SM-T805 (Cellular and WIFI)
Did anything happen to it before this started happening? When was the last time you used it, and did you see any issues then? Did you ever have any issues before? If it has dropped there is a good chance that just the screen broke and you will need to replace the screen.