The main optical parameters of metal-coated mirrors are as follows:

Reflectivity: This is an important parameter of metal-coated mirrors, which determines the degree of light reflection. The higher the reflectivity, the better the reflection performance. The reflectivity of common metal mirrors can reach over 90%. The reflectivity depends on factors such as the type of metal, surface treatment process, and the angle of light incidence. Meanwhile, the thickness of the metal film also affects the reflection performance. By controlling the thickness of the metal film, the reflection and transmission of light at specific wavelengths can be achieved. 

Bandwidth: It refers to the reflection performance within a specific wavelength range. The reflection bandwidths of different metal-coated mirrors vary, and products within a specific wavelength range can be selected according to requirements. 

Wavelength range: Metal-coated mirrors can reflect light in different wavelength ranges. Common wavelength ranges cover visible light, infrared light, ultraviolet light, etc. 

Heat resistance: Metal-coated mirrors need to have a certain high-temperature resistance, especially in high-energy optical systems such as lasers, where they should be able to withstand the reflection work in high-temperature environments. 

Surface flatness: It has a significant impact on the reflection performance. The higher the surface flatness, the better the reflection performance.

 Surface figure accuracy: For example, the optical error RMS of CVI metal-coated mirrors is less than λ/50. Higher surface figure accuracy can provide customers with high-quality image.

 Surface roughness: The surface roughness of some metal-coated mirrors can reach 3 - 5 Å. 

Damage threshold: This parameter is crucial in scenarios such as high-power and precision laser applications. For instance, CVI mirrors have a relatively high coating damage threshold.