I can reproduce with:
libcairo2 1.6.0-0ubuntu1 (cairo 1.6.0) libpoppler2 0.6.4-1 (poppler 0.6.4) evince 2.22.1.1-0ubuntu1 (evince 2.22.1)
It happens in the Print Preview even. The text is blurry but the equation looks sharp.
I can reproduce with:
libcairo2 1.6.0-0ubuntu1 (cairo 1.6.0)
libpoppler2 0.6.4-1 (poppler 0.6.4)
evince 2.22.1.1-0ubuntu1 (evince 2.22.1)
It happens in the Print Preview even. The text is blurry but the equation looks sharp.