Liquid level height controlled multi-material photocuring 3D printing system and method

The invention discloses a liquid level height controlled multi-material photocuring 3D printing system and method, the liquid level height controlled multi-material photocuring 3D printing system comprises an optical platform and a liquid level sensing device; a liquid level sensing device is arranged on the side surface of the optical platform; the method comprises the following steps: S1, filling the same resin into a resin pool and an injector, and communicating the liquid resin in the resin pool with the injector through a hose so as to add or reduce the resin into the resin pool and change the liquid level height of the resin in the resin pool; s2, the height of a liquid level detection sensor is adjusted, so that the height of the liquid level detection sensor is within the normal working height range, and the liquid level layer thickness of printing resin and the initial liquid level position are set; the problem that the printing quality is affected due to the fact that the design layer thickness is d