The invention discloses a traffic signal lamp suitable for being used by normal and colorblind people. The traffic signal lamp is formed by a traffic signal lamp body. A layer of interference film is installed outside the traffic signal lamp body. A layer of Newton ring film is installed outside a red signal lamp. A layer of wedge interference film is installed outside a green signal lamp. Through adding one layer of the interference film outside traffic lights, colorblind or color-weakness people can distinguish traffic signals through different shapes of stripes displayed on the film.