A transparent substrate including an antireflection coating, made from a stack of thin layers of dielectric material having alternately high and low refractive indices. This stack includes a high-index first layer having a refractive index n, of between 1.8 and 2.2 and a geometrical thickness e₁ of between 5 and 50 nm, a low-index second layer having a refractive index n₂ of between 1.35 and 1.65 and a geometrical thickness e₂ of between 5 and 50 nm, a high-index third layer having a refractive index n₃ of between 1.8 and 2.2 and a geometrical thickness e₃ of between 70 and 120 nm, and a low-index fourth layer having a refractive index n₄ of between 1.35 and 1:65 and a geometrical thickness e₄ of at least 80 nm.