\documentclass{article}
\usepackage[abs]{overpic}
\usepackage[pdfstartview=FitH]{hyperref}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\makeatletter
\InputIfFileExists{\jobname.zom}{}{}
\newwrite\zoomdat
\immediate\openout\zoomdat=\jobname.zom
\def\marklowerleft#1{%
  \pdfsavepos%
  \write\zoomdat{%
    \string\expandafter\string\def\string\csname\space #1.llx\string\endcsname{%
      \the\pdflastxpos}%
    \string\expandafter\string\def\string\csname\space #1.lly\string\endcsname{%
      \the\pdflastypos}%
  }%
  \ifcsname  #1.llx\endcsname\ifcsname  #1.urx\endcsname%
  \pdfdest name {#1.to} fitr width \numexpr
    \csname #1.urx\endcsname-\csname #1.llx\endcsname\relax sp height \numexpr
    \csname #1.ury\endcsname-\csname #1.lly\endcsname\relax sp 
  \immediate\pdfannot width \numexpr
    \csname #1.urx\endcsname-\csname #1.llx\endcsname\relax sp height \numexpr
    \csname #1.ury\endcsname-\csname #1.lly\endcsname\relax sp {%
      /Subtype/Link/H/N/Dest (#1.back)
      /Border [0 0 0]
  }%
  \fi\fi%
}
\def\markupperright#1{%
  \pdfsavepos%
  \write\zoomdat{%
    \string\expandafter\string\def\string\csname\space #1.urx\string\endcsname{%
      \the\pdflastxpos}%
    \string\expandafter\string\def\string\csname\space #1.ury\string\endcsname{%
      \the\pdflastypos}%
  }%
}
\def\zoomto#1#2{%
  \leavevmode%
  \raisebox{\baselineskip}[0pt][0pt]{\pdfdest name {#1.back} fith}%
  \pdfstartlink user {%
    /Subtype /Link
    /Border [\@pdfborder]%
    /C [\@linkbordercolor]%
    /H/N%
    /Dest (#1.to)%
  }\strut#2%
  \pdfendlink%
}
\makeatother
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{document}

Das \zoomto{auge}{Auge} des Tigers.

\begin{center}
\begin{overpic}[grid,scale=0.5,unit=1bp]{tiger.pdf}
  \put(110,180){\marklowerleft{auge}}
  \put(140,200){\markupperright{auge}}
\end{overpic}
\end{center}

\end{document}