An　optical　measurement　system,　which　is　capable　of　vibration　measurement　and　response-only　experimental　modal　analysis　for　beam-like　structures,　is　reported　by　taking　the　concept　of　2-dimensional　optical　coherence　vibration　tomography　technique.　In　the　proposed　approach,　it　requires　only　quasi-interferogram　fringe　patterns　as　sensors　and　a　high-speed　camera　as　a　detector.　Experimental　results　of　beam-like　structures　subjected　to　swept　and　harmonic　excitations　are　demonstrated.　The　key　advantage　of　the　proposed　method　is　the　high　spatial　and　temporal　resolution　with　simultaneously　measuring　the　absolute　displacement　of　multiple　points　along　the　beam-like　structures　without　point-by-point　optical　scanning.　Without　any　vibration　excitation　information,　the　quasi-optical　coherence　vibration　tomography　technique　system　can　capture　structural　modal　parameters.　Therefore,　it　is　a　response-only　experimental　modal　analysis　method,　making　it　attractive　for　the　structural　health　monitoring　applications　in　the　multiple-point　measurement　of　real　engineering　structures　with　the　absence　of　vibration　input　information.　Copyright　©　2017　John　Wiley　&　Sons,　Ltd.