optical amplitude modulator
光振富调制器

• focusing optices
• focusing range
• focusing reflector
• focusing ring
• focusing scale
• focusing screen
• focusing Soller-slit system
• focusing spectrometer
• focusing spindle
• focusing stop
• focusing system
• focusing telescope
• focusing telescope objective
• focus lamp
• focus mask
• focus-out
• focus plate
• focus point
• focus range
• focus ring
• focus shift
• fog
• fog density
• fogged
• foggy environment