車灯亮度是聯邦法規範,如果聚焦不良而必須增強灯泡亮度,可能引發過多炫光影響對向車子,是會被取締

The Code of Federal Regulations indicates that the luminous intensity of headlights must be between 500 and 3,000 candelas. Since very few people know what a candela is or how to measure it, the DOT and SAE certify headlights that are legal for use in the United States. As long as the headlight is labeled as DOT or SAE approved, it's likely legal to use in all 50 states.