Hello SP4_user11,
A lot of work was done in Windows 10 to support high resolution screens, such as the Surface Pro 3, Surface Pro 4, Surface Book, and third-party laptops and tablets with screen resolutions above 1080p. However, there are issues that occur when using Office apps on these devices when connecting to an external monitor with a lower resolution.
To find out more about what has been improved and what is still being worked on, please check out these articles:
- High-DPI Scaling Improvements for Desktop Applications in the Windows 10 Creators Update
- Office apps appear the wrong size or blurry on external monitors
The current and future improvements are dependent on having Windows 10 Creators Update installed. So if you have not yet updated, please start with that.
Best Regards
, and select Control Panel.