absorption-dip
(1)吸收(引起的)倾斜
(2)吸收(引起的)凹陷

• vacuum seal
• vacuum spectral region
• vacuum spectrograph
• vacuum stability
• vacuum system
• vacuum tank
• vacuum technique
• vacuum telescope
• vacuum testing
• vacuum thermometer
• vacuum thermo-pile
• vacuum-tight
• vacuum tightness
• vacuum tube
• vacuum tube oscillator
• vacuum ultra-violet
• vacuum ultra-violet holography
• vacuum ultra-violet laser
• vacuum ultraviolet lasers
• vacuum ultra-violet spectrograph
• vacuum value
• vacuum vapor deposition method
• vacuum vessel
• vacuum wax
• vague image