An optical assembly, comprising: an optical body having an optical window ; an optical device protected by the optical body; and a cleaning apparatus for cleaning the optical window of the optical body protecting the optical device, the optical device having a line of sight through the optical window, the cleaning apparatus comprising: - a fluid applicator associated with the optical body and configured to apply a liquid film to cover the optical window; - a wiper associated with the optical body; - an actuator configured to: cause relative movement between the optical body and the wiper to initiate a first stage of a cleaning cycle wherein at least some contaminants that land on the liquid film are removed from the optical window by the wiper; and cause relative movement between the optical body and the fluid applicator to initiate a second stage of the cleaning cycle wherein the liquid film is applied by the fluid applicator to cover the optical window, the liquid film remaining on the optical window and impeding adhesion of contaminants to the optical window underlying the liquid film. an optical body having an optical window ; an optical device protected by the optical body; and a cleaning apparatus for cleaning the optical window of the optical body protecting the optical device, the optical device having a line of sight through the optical window, the cleaning apparatus comprising: - a fluid applicator associated with the optical body and configured to apply a liquid film to cover the optical window; - a wiper associated with the optical body; - an actuator configured to: cause relative movement between the optical body and the wiper to initiate a first stage of a cleaning cycle wherein at least some contaminants that land on the liquid film are removed from the optical window by the wiper; and cause relative movement between the optical body and the fluid applicator to initiate a second stage of the cleaning cycle wherein the liquid film is applied by the fluid applicator to cover the optical window, the liquid film remaining on the optical window and impeding adhesion of contaminants to the optical window underlying the liquid film. - a fluid applicator associated with the optical body and configured to apply a liquid film to cover the optical window; - a wiper associated with the optical body; - an actuator configured to: cause relative movement between the optical body and the wiper to initiate a first stage of a cleaning cycle wherein at least some contaminants that land on the liquid film are removed from the optical window by the wiper; and cause relative movement between the optical body and the fluid applicator to initiate a second stage of the cleaning cycle wherein the liquid film is applied by the fluid applicator to cover the optical window, the liquid film remaining on the optical window and impeding adhesion of contaminants to the optical window underlying the liquid film. cause relative movement between the optical body and the wiper to initiate a first stage of a cleaning cycle wherein at least some contaminants that land on the liquid film are removed from the optical window by the wiper; and cause relative movement between the optical body and the fluid applicator to initiate a second stage of the cleaning cycle wherein the liquid film is applied by the fluid applicator to cover the optical window, the liquid film remaining on the optical window and impeding adhesion of contaminants to the optical window underlying the liquid film. <EOS>