root-mean-square displacement
均方根位移

• real transition
• realuminizing
• real-valued intensity
• reamer
• reaming
• rear
• rear finder
• rear focus
• rear nodal point
• rear node
• rear operating aperture
• rear-silvered mirror
• rear view
• rear-vision mirror
• reasonable value
• reassembly
• rebatron
• rebound
• recalescence point
• recalibration
• recasting
• receiver
• receiver ,Rx
• receiving aperture
• receiving objective