Ultraviolet laser 3D printing method for precise temperature control of polymer material and device thereof

An ultraviolet laser 3D printing device, comprising:

• a thermostatic chamber for maintaining a constant temperature;
• a processing platform disposed in the thermostatic chamber for supporting an object being printed;
• a powder laying device for applying a polymer material on the processing platform;
• a laser head disposed above the processing platform for emitting a laser beam;
• a scanning galvanometer that deflects the laser beam onto the processing platform;
• a non-contact type temperature monitoring device disposed at a distance above the processing platform;
• a computer control system coupled to the laser head and the temperature monitoring device for controlling a power and a movement trajectory of the laser head, and for receiving a temperature signal from the temperature monitoring device,
• wherein the laser head comprises an inner die and an outer die coaxially disposed in the laser head, and one or more pieces of graded filters are disposed in a gap between the inner die and the outer die, and wherein a laser transmittance of each of the one or more pieces of graded filters reduces in a radial direction from the inner die to the outer die,
• wherein the laser beam is ultraviolet laser having a wavelength of 190 nm to 380 nm, and
• wherein the laser beam comprises a core laser beam emitted from the inner die and a peripheral beam emitted from the outer die.