What do the red and white circles on Canon SLR lens mean?

Red circle: professional Quan Huafu lens, good workmanship, dustproof and waterproof beads, good imaging quality and relatively large maximum aperture. The maximum aperture of various zoom lenses is constant, and many ultra-low dispersion lenses, aspherical lenses and even fluorite lenses are usually used.

White circle: Generally, EF-S lenses are special lenses for APS-C frames. The others are aperture lenses, that is, Quan Huafu lenses.

Canon's red circle lens is marked with L (luxury), which is the characteristic of Canon's high-quality lens. Its handling, image quality and performance are better than ordinary lenses. Only high-end lenses with excellent optical performance that pass Canon's internal special standards have the L logo.

Extended data:

Features of Canon lens:

1, l (red circle): l is the abbreviation of Luxury, indicating that this lens belongs to high-end lens. This logo is only given to high-end lenses with excellent optical performance that have passed Canon's internal standards.

2.USM/STM (red and white circle): indicates the type of auto-focus driving motor. Includes STM stepping motor and USM ultrasonic motor.

3.DO (green circle): refers to the lens with DO lens (multilayer diffractive optical element). Its characteristic is that diffraction can be used to change the optical path, and all kinds of aberrations can be effectively compensated by only one lens, in addition, the lens weight can be reduced.

Canon official website-Interpretation of Lens Names