https://pubmed.ncbi.nlm.nih.gov/19116201/
We consider the problem of registering (aligning) two images to sub-pixel accuracy by optimization of objective functions constructed from the images'...
sub pixelimage registrationinterpolationartifacts
https://www.grc.com/ct/cleartype.htm
A complete and clear explanation of Microsoft's 'ClearType' Technology -- including a freeware demo application.
sub pixelfont renderinggrctechnology