optically flat filter
光学平面滤光片

• secondary wavelet
• secondary winding
• second electron lens
• second focal length
• second-harmonic
• second harmonic generation
• second of arc
• second of time
• second order aberration
• second order coherence function
• second order spatial coherence
• second radiation constant
• section
• sectional
• sectional area
• sectional arrangement drawing
• sectionalization
• sectional view
• section pronjector
• sector
• sector arm
• sector gear
• sectorial wave
• sector shaft
• sector shutter