A thin layer of reflective material applied to one side of a glass substrate, typically for the purpose of creating a mirror. This reflective coating allows the glass to function as a mirror by bouncing back light that strikes its surface. Without this backing, light would simply pass through the glass. An example is the reflective surface seen on standard bathroom mirrors.
The application of this reflective layer is crucial for the functionality of mirrors used in a wide variety of applications, ranging from personal grooming and interior decoration to scientific instruments and optical devices. Historically, mercury was used; however, due to toxicity concerns, silver, and subsequently aluminum, became preferred materials. The reflective surface provides the necessary optical properties for image reflection, enhancing visibility and light amplification within optical systems.
