我尝试使用 Source Han Serif (otf) 作为 XeTex 的主要字体（通过 LyX），但输出 pdf 中的数字不可选择。其他一些 otf 字体（例如 Cabin）在输出中可选择数字时效果很好。此外，Source Han Sans 也可以输出可选择的数字，这对我来说毫无意义。
以下是出口透气产品：
%% LyX 2.3.0 created this file. For more info, see http://www.lyx.org/.
%% Do not edit unless you really know what you are doing.
\documentclass[11pt,english,UTF8]{article}
\usepackage[a4paper]{geometry}
\geometry{verbose,tmargin=1in,bmargin=1in,lmargin=1.5in,rmargin=1.5in}
\setcounter{secnumdepth}{2}
\setcounter{tocdepth}{2}
\setlength{\parskip}{\smallskipamount}
\setlength{\parindent}{0pt}
\usepackage{color}
\usepackage{microtype}
\usepackage[unicode=true,
bookmarks=true,bookmarksnumbered=true,bookmarksopen=true,bookmarksopenlevel=1,
breaklinks=false,pdfborder={0 0 0},pdfborderstyle={},backref=false,colorlinks=true]
{hyperref}
\hypersetup{
linkcolor=blue, citecolor=black, urlcolor=blue, filecolor=blue,pdfpagelayout=OneColumn, pdfnewwindow=true, pdfstartview=XYZ, plainpages=false}
\makeatletter
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Textclass specific LaTeX commands.
\newlength{\lyxlabelwidth} % auxiliary length
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% User specified LaTeX commands.
\usepackage[UTF8]{ctex}
\setmainfont[Mapping=none, ItalicFont=Source Han Serif SC, ItalicFeatures=FakeSlant, AutoFakeSlant]{Source Han Serif SC}
\setsansfont[Mapping=none]{Source Han Sans SC}
\setmonofont{Courier 10 Pitch}
\setCJKmainfont[
BoldFont=Source Han Serif SC, BoldFeatures=FakeBold,
ItalicFont=Source Han Serif SC, ItalicFeatures=FakeSlant]{Source Han Serif SC}%
\setCJKsansfont[
BoldFont=Source Han Sans SC, BoldFeatures=FakeBold,
ItalicFont=Source Han Sans SC, ItalicFeatures=FakeSlant]{Source Han Sans SC}
% Define hyphenation
\pretolerance=500
\tolerance=9000
\emergencystretch=0pt
\righthyphenmin=4
\lefthyphenmin=4
\makeatother
\usepackage{polyglossia}
\setdefaultlanguage[variant=american]{english}
\usepackage[style=ieee,backend=bibtex8]{biblatex}
另外，关于我的 XeTeX 版本：
$ xelatex --version
XeTeX 3.14159265-2.6-0.99992 (TeX Live 2015/Debian)
kpathsea version 6.2.1
Copyright 2015 SIL International, Jonathan Kew and Khaled Hosny.
There is NO warranty. Redistribution of this software is
covered by the terms of both the XeTeX copyright and
the Lesser GNU General Public License.
For more information about these matters, see the file
named COPYING and the XeTeX source.
Primary author of XeTeX: Jonathan Kew.
Compiled with ICU version 55.1; using 55.1
Compiled with zlib version 1.2.8; using 1.2.8
Compiled with FreeType2 version 2.5.5; using 2.5.5
Compiled with Graphite2 version 1.3.6; using 1.3.10
Compiled with HarfBuzz version 1.0.1; using 1.0.1
Compiled with libpng version 1.6.17; using 1.6.17
Compiled with poppler version 0.41.0
Compiled with fontconfig version 2.11.1; using 2.11.94