Hi Anil,
Looks like you are running MATLAB on Linux on a high resolution 4K display and it is not scaling properly for different resolutions.
Please refer to the below post by MathWorks Support Team in which they have mentioned that MATLAB supports High DPI screens on Linux starting from R2017b and provided the steps for the same:
"Does MATLAB support High DPI screens on Linux?” : https://www.mathworks.com/matlabcentral/answers/406956-does-matlab-support-high-dpi-screens-on-linux
Hope it helps.