light-value scale
光值标尺，曝光指数标尺

• GSGG GSAG laser crystals
• guard
• guard wire
• gudden-pohl effect
• guidance
• guidance accuracy
• guidance beam
• guidance control
• guidance information
• guidance package
• guide
• guide bar
• guide curve
• guided mode
• guided ray
• guided transmission
• guided wave
• guide face
• guide grid
• guide line
• guide locating
• guide number
• guide number letter scale
• guide pin
• guide pulley