An optical security component intended to be observed in reflection, with the naked eye, along at least one first observation face , comprising: - a first layer of dielectric material, which is at least partially transparent in the visible range, having a first refractive index (n 1 ), said first layer comprising at least one first region (R 1 ) that is uniformly microstructured so as to form a first diffractive microstructure (S 1 ); - at least one first metallic reflective layer , which is deposited on said at least one first microstructured region and forms one or more opaque reflective elements (O i ), each opaque reflective element forming a line with a width that is strictly smaller than 1 mm, the assembly comprising the one or more opaque reflective elements forming a first recognizable graphical element; - at least one first transparent reflective layer , made of dielectric material, having a second refractive index (n 2 ), which is deposited on said at least one first microstructured region and forms one or more transparent reflective elements (T i ), a minimum dimension of each transparent reflective element being greater than 2 mm, the assembly comprising the one or more transparent reflective elements forming a second recognizable graphical element; - a cover layer , made of dielectric material, which is at least partially transparent in the visible range, having a third refractive index (n 3 ) close to the first refractive index (n 1 ), covering said first layer and said at least one first metallic reflective layer and at least one first transparent reflective layer , such that said cover layer is in direct contact with said first layer in the areas of said first layer without opaque or transparent reflective elements, - the optical security component exhibiting, in reflection, a dynamic visual effect obtained by tilting the component. - a first layer of dielectric material, which is at least partially transparent in the visible range, having a first refractive index (n 1 ), said first layer comprising at least one first region (R 1 ) that is uniformly microstructured so as to form a first diffractive microstructure (S 1 ); - at least one first metallic reflective layer , which is deposited on said at least one first microstructured region and forms one or more opaque reflective elements (O i ), each opaque reflective element forming a line with a width that is strictly smaller than 1 mm, the assembly comprising the one or more opaque reflective elements forming a first recognizable graphical element; - at least one first transparent reflective layer , made of dielectric material, having a second refractive index (n 2 ), which is deposited on said at least one first microstructured region and forms one or more transparent reflective elements (T i ), a minimum dimension of each transparent reflective element being greater than 2 mm, the assembly comprising the one or more transparent reflective elements forming a second recognizable graphical element; - a cover layer , made of dielectric material, which is at least partially transparent in the visible range, having a third refractive index (n 3 ) close to the first refractive index (n 1 ), covering said first layer and said at least one first metallic reflective layer and at least one first transparent reflective layer , such that said cover layer is in direct contact with said first layer in the areas of said first layer without opaque or transparent reflective elements, - the optical security component exhibiting, in reflection, a dynamic visual effect obtained by tilting the component. <EOS>