length-measuring instrument
(1)长度计量仪器
(2)测长仪

• air chuck
• air cleaner
• air-conditioning system
• air-cored
• aircraft landing lamp
• air damping
• air-defence sighting telescope
• Air Dose
• air-filled thermocouple
• air filter
• air gap
• air gauge
• air-glass reflection
• air-glass surface
• Airglow
• airglow emission
• airglow intensity
• air-in
• airing
• air knife coating
• air level
• air light
• airload
• air-locked
• air-map