Abstract: An optical amplifier includes a pump light source, a coupler, a gain medium, and a gain flattening filter. A gain curve of the optical amplifier is symmetric relative to a target gain curve. Distortion states of any two symmetric gain curves are opposite. The pump light source is configured to provide pump light. The coupler is configured to couple the pump light to the gain medium. The gain medium is configured to amplify, based on the pump light, signal light input to the optical amplifier. The gain flattening filter is configured to filter the amplified signal light, and output the filtered signal light.

Abstract: This application provides example optical switching methods and example apparatuses. One example method includes generating K images that are consecutive in time sequence, where a first wavelength channel and at least one second wavelength channel are switched to a blocking state through a same image in the K images, and a value of K depends on a quantity of times that attenuation adjustment is performed for switching the first wavelength channel from a normal state to the blocking state. Information about the K images can then be sent to an optical switching element to enable the optical switching element to perform attenuation adjustment on the first wavelength channel and the at least one second wavelength channel.