我正在用 TeX 写一本书，这很不错，但直到最近我才意识到我的本地 TeX 到 PDF 导出看起来有多丑陋：
作为参考，左边是我的，右边是我随机获得的 Linux 机器生成的。看看它有多清晰？我有点困惑为什么会这样。
这是我的本地pdflatex版本：
pdfTeX 3.14159265-2.6-1.40.15 (TeX Live 2014)
kpathsea version 6.2.0
Copyright 2014 Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
There is NO warranty. Redistribution of this software is
covered by the terms of both the pdfTeX copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the pdfTeX source.
Primary author of pdfTeX: Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
Compiled with libpng 1.6.10; using libpng 1.6.10
Compiled with zlib 1.2.8; using zlib 1.2.8
Compiled with xpdf version 3.03
以及 Linux 机器的：
pdfTeX using libpoppler 3.141592-1.40.3-2.2 (Web2C 7.5.6)
kpathsea version 3.5.6
Copyright 2007 Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
Kpathsea is copyright 2007 Karl Berry and Olaf Weber.
There is NO warranty. Redistribution of this software is
covered by the terms of both the pdfTeX using libpoppler copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the pdfTeX using libpoppler source.
Primary author of pdfTeX using libpoppler: Peter Breitenlohner (eTeX)/Han The Thanh (pdfTeX).
Kpathsea written by Karl Berry, Olaf Weber, and others.
Compiled with libpng 1.2.46; using libpng 1.2.49
Compiled with zlib 1.2.3; using zlib 1.2.3
Compiled with libpoppler
编辑：我刚刚意识到 Linux 机器使用libpoppler而我使用xpdf。这可能是原因吗？我该如何切换？