Intelligent　production　of　small　modulus　powder　metallurgy　gearing　requires　rapid　and　accurate　measurement　to　ensure　product　quality.　Currently,　the　contact　measurement　method　exemplified　by　gear　measuring　centers　lack　efficiency　and　require　gear　mounting　reference,　which　prevent　them　from　meeting　the　requirements　for　on-line　inspection　of　small　modulus　gears.　Therefore,　an　optical　method　of　gears　was　intensively　researched.　It　combined　the　advantages　of　laser　and　vision　inspection,　which　meet　the　requirements　for　accuracy　and　efficiency　in　on-line　inspection.　Based　on　the　measurement　principle　of　the　line　laser　sensor　and　vision　camera,　a　model　of　the　measurement　system　was　established;　a　standard　block　was　designed　to　calibrate　the　system.　The　surface　data　of　tooth　flank　were　acquired　by　laser　scanning　and　evaluated　to　analysis　the　accuracy.　The　result　of　method　was　validated　by　comparison　with　the　gear　measurement　center.　Both　are　of　good　agreement.　Sufficient　experiments　verify　the　feasibility　of　proposed　method　for　on-line　inspection.　©　2024　IOP　Publishing　Ltd.