Lots more information needed to answer your question.
Have you updated 12 to 12.1 yet? If not, please do so.
Where is the text coming from that is not sharp and clear....Timeline text files created in the project's Titler or text which is displayed in a movie file that you have imported into the project as source media? Or, are you referring to text in the Movie menus and its Movie menu Preview?
Is the problem using the regular view or the Full Screen view?
Also, what project preset have you (manually) or the project (automatically) set for this project?
If not sure, please let us know the readings for Editing Mode, Timebase, Frame Size, Pixel Aspect Ratio found Edit Menu/Project Settings/General.
Let us start here and then decide what next based on your answers.
i mean the text in the Movie menus and its Movie menu Preview .
i still have version12, how can i update it 12.1 ??
Thanks for the follow up with additional information regarding your font clarity issue.
The best judge of quality for those menus is the playback of the end product disc using your player of choice.
The Movie Menu Previews are typically poor - regular view or full screen view within the project.
The clarity of the text in the Movie menus can be influenced by
a. size of font
b. choice of font
c. background for font
Are you working in SD or HD project? Are you working with Motion Buttons?
Have you found any differences in text clarity going to other menu(s)?
What disc menu is involved in this thread question?
Please review and consider and then we can decide what next.