GB/T 5137.2-2020 was implemented on February 1, 2021, replacing the old version of the standard. It specifies four test methods for automotive safety glass: visible light transmittance, secondary image deviation, optical distortion, and visible light reflectance. These methods are applicable to the optical performance testing of automotive safety glass. The tests must be conducted in an environment of 20℃±5℃ and a relative humidity of 40%-80%. Core instruments such as transmittance measuring devices, target-type light source instruments, and spectrophotometers are used to ensure the accuracy of the testing through standardized procedures. This standard provides a unified basis for the quality control of the optical performance of automotive safety glass, directly impacting the clarity of the driver's vision and road safety.