High reflective glass beads can be regarded as spherical lenses. When a reflective layer is placed at its focal point, it can incident light well Ground returns to the light source. The position of the focus of the glass beads depends on the refractive index of the glass beads.
High index reflective glass beads require higher retro-reflectivity, where top data is above 2.2 is required, we use special glass which is more clear and lower on heavy metal with high reflective index and more stable performance.
High index reflective glass beads are a new type of silicate material with good retro-reflectivity when the refractive index is between 1.9 and 2.2. That is, when a beam of light illuminates the surface of the bead at any angle within a certain range, it is concentrated on a specific reflective layer behind the bead due to the refraction of the bead, and the reflective layer reflects the light back in parallel along the direction of the light source.