When you boot a Windows 8 device that is encrypted using BitLocker, the BitLocker PIN or Recovery Password Entry screen, fonts and text may appear with reduced clarity (blurry).
This issue can occur if you are running an incompatible BIOS/Firmware.
Contact the hardware manufacture to check for a BIOS/Firmware update that is tested and supported for Windows 8.
To properly support booting Windows 8 in UEFI mode with BitLocker enabled, ensure that the system is on UEFI firmware version 2.3.1 and that the UEFI firmware is in native mode without a Compatibility Support Module (CSM) for BIOS mode enabled.
Article ID: 2782897 - Last Review: Nov 12, 2012 - Revision: 1
Windows 8, Windows 8 Enterprise, Windows 8 Pro