Hot filament tension control method, controller and chemical deposition equipment

The invention discloses a hot wire tension control method, a controller and chemical deposition equipment. The hot wire tension control method comprises the following steps: acquiring real-time temperature information and/or real-time image information of a preset area where a hot wire in a reaction cavity is located; judging whether the hot wire sags or not according to the real-time temperature information and/or the real-time image information; if it is judged that the hot wire droops, the tensile force borne by the hot wire is adjusted so that the hot wire can restore the straightening state. When the hot wire droops, the distance between the hot wire and the preset area changes, so that the temperature of the preset area changes, and the image of the hot wire itself also changes; by acquiring the real-time temperature information and/or the real-time image information of the preset area, whether the hot wire sags or not can be known in real time according to the real-time temperature information and/or t