Optical scanning device and image forming apparatus provided with the same

摘要

An optical scanning device includes an air-tight casing, an air-tight container and a tube-like member. The air-tight casing is configured to accommodate at least a polygon mirror and a driving unit that rotates the polygon mirror. The air-tight container is disposed at a distance from the air-tight casing and outside an outer wall surface vertically above the air-tight casing. The tube-like member is configured to communicatively connect an inside of the air-tight casing and an inside of the air-tight container.