Also, system graphics drivers and even the JRE could be part of the issue.
See some solutions below.
3.1 Change Interface Settings
If the MPLAB X IDE desktop looks “fuzzy”, modify the interface behavior.
To change default options:
Find the mplab_ide.conf file under <MPLAB X IDE install directory>\mplab_platform\etc.
Open the file in an editor and find default_options=.
Insert -J-Dsun.java2d.dpiaware=false into the string and save.
Restart MPLAB X IDE.
To override scaling behavior:
Right click on a shortcut (such as the desktop icon) or an executable file (mplab_ide.exe or mplab_ide64.exe) and select “Properties”. Find the IDE executables under <MPLAB X IDE install directory>\mplab_platform\bin.
Click on the “Compatibility” tab of the “Properties” dialog.
In the “Settings” section, select an option worded as “Override High DPI scaling behavior”.
Restart MPLAB X IDE.
3.2 Change Font Size
To set the basic font size: Use the following executable option: –-fontsize=size, where size is in points. See also: http://wiki.netbeans.org/FaqFontSize.
To clear font settings: Erase, rename or move the Cache and/or User directories (see Help>About for locations). Then restart MPLAB X IDE.