secondary chromatic aberration
二次像差

• trochotron
• troland
• tropia
• tropic
• tropical
• tropical climate
• tropopause
• troposcatter
• troposphere
• tropospheric
• tropospheric wave
• trouble
• trouble-proof
• trough
• trough reflector
• true aperture
• true field
• true focus
• true image
• trueness
• truer
• true temperature
• true-up
• true value
• true zenith distance