optical reflector
(1)反光镜
(2)光反射器

• guiding prism
• Guinier focusing camera
• gum
• gun
• gun camera
• gun-laying reticle
• Gunn effect oscillator
• gunn errer
• gun sight
• gun-sight aiming point camera
• guy wire
• gypsum
• gyration
• gyrator
• gyre
• gyro
• gyrobearing
• gyro black assembly
• gyroclinometer
• gyrocompass
• gyro frequency
• gyro horizon
• gyro-level
• gyromagnetic effect
• gyromagnetic ratio