The invention relates to a low-light-loss tube lamp adjusting structure. The low-light-loss tube lamp adjusting structure is connected between a tube lamp
light source part and a light adjusting part, and comprises an arc-shaped guide part arranged on the light adjusting part and a sliding part arranged on the
light source part, wherein the sliding part moves along the arc-shaped guide part. The low-light-loss tube lamp adjusting structure has the beneficial effects that the angle adjustment is performed on a
light source through the arc-shaped guide structure, and compared with the prior art, under the conditions of the same size of a lamp body, the same
beam angle and the same adjusting angle, the light loss is reduced by more than 75% in the adjustment process compared with that of the prior art; the structure of an adjusting device is simple, and parts are easy to manufacture; and due to the fact that the light loss is greatly reduced after adjustment, the low-light-loss tube lamp adjusting structure is of great significance for achieving multiple purposes of one lamp, reducing the models of lamps, reducing the number of molds to be manufactured, and saving social resources.