Reason: The resolution of the computer is lower than the resolution of projection, which will cause blur when projecting.

1. First, open the PPT slide application, enter the slide editing homepage, and select to open the PPT file to be projected.

2. After opening the PPT file, click the "Design" function bar in the top menu bar to open the "Page Setup" option below the file.

3. Then set the PPT page to be larger than the original page in the pop-up page setup page, and press enter to confirm. You can experiment repeatedly to find the most suitable value.

4. Then the problem can be solved by properly enlarging the pictures in PPT slides.