Optan奥普通牌照相机optvi.选择；决定optimizing control method[电] 择优控制法optoelectronics and laser光电子学与激光技术opto-electron technique光电子技术optomechanical instrument光力学仪器Optoelectronic oscillator光电振荡器Optima Puppy Dry Dog Food专用干式狗opto-electronic antenna光电天线optoelectronic inspecting光电检测opto-electrical encoder光电编码器optoelectronic technology光电技术