Aperture　technology,　which　influences　the　combining　efficiency,　is　the　key　factor　for　Coherent-Beam-Combining　(CBC).　By　using　beam　combiner　with　high　performances,　coherent　combining　of　fiber　lasers　can　provide　the　chance　to　increase　the　output　intensity　more　efficiently.　This　paper　presents　a　method　to　manufacture　the　beam　combiner　for　CBC　by　using　a　thin-film　coated　glass　plate.　This　method　can　increase　the　effective　filling　factor　of　aperture,　and　therefore　eliminate　far-field　side-lobes　by　enlarging　the　number　of　sub-apertures　and　decreasing　the　distance　between　the　sub-apertures　for　an　output　aperture　with　a　constant　size.　The　fabrication　of　this　thin-film　coated　glass　costs　less　and　the　coated　glass　has　better　stability　than　other　beam　combiners.　In　order　to　earn　high　efficiency　for　CBC,　we　also　exploit　physical　and　geometrical　optics　to　build　the　model.　Theoretically,　this　method　can　raise　the　coherent　combining　efficiency　almost　to　100%.　Additionally,　based　on　this　method,　a　new　conception　of　Multiple-beam　Interference　of　Multi-beams　is　offered.