Femtosecond laser 3D printing, based on two-photon polymerization, multi-photon polymerization technology to achieve high-speed and accurate visual printing manufacturing of hundred-nanometer scale micro and nano components.
Feature：
- Utilizes high-frequency, high-energy femtosecond laser with ultra-high stability and continuous output.
- Wavelengths: 1030nm, 515nm, 343nm (optional).
- Pulse width ≤ 250fs to 10ps.
- Single pulse energy up to 100μJ at 60kHz.
- XYZ multi-axis air-floating motion platform, multi-axis formation optional.
- XYZ repeat positioning accuracy: ±200nm.
- Max speed: 200mm/s.
- PSO function linkage control.
- Main interface for direct adjustment of displacement and speed; integrated machine vision for real-time process monitoring.
Customizable:Optical waveguides, fiber Bragg gratings (FBG), super-diffraction 3D printing, and hybrid manufacturing systems.
Four kinds of femtosecond printing system configuration scheme:
1) galvanometer scanning system: As shown in Figure (c), traditional two-photon processing is mainly divided into two categories;
One kind of focus does not move, the 3D displacement table drives the photoresist sample to move, but the 3D motion table has a slow scanning speed and slow response.
The other is the combination of two-dimensional XY scanning galvanometer and one-dimensional Z-displacement table as a scanning system, which has the advantages of high scanning speed and fast dynamic response, and high processing efficiency.
2) Submerged scanning system: As shown in Figure (d), the height of structural processing that can be realized is limited by the working distance of the microscope objective when the two-photon processing of some structures with high depth ratio and large size is carried out.
By using the immersed system objective lens directly into the liquid photoresist, instead of focusing through the glass substrate, using the large travel range of the electric Z drive of the objective lens, the structural height of up to a few millimeters can be achieved.
At the same time, it can also avoid the problem of machining structure deviation caused by the mismatch of refractive index of air-photoresist with low power air objective lens.
3) STED (Stimulated emission depletion) assisted two-photon processing system: As shown in Figure (e), this system is characterized by introducing another suppression beam in the shape of a circular focal spot on the basis of the polymerization initiated by the first femtosecond laser to make the excited molecules in the ring region reverse transition to a stable state, thereby inhibiting the photopolymerization reaction in the ring focal spot and compress the photopolymerization point diffusion function to make the polymerization process effective.The area is reduced to further improve the processing resolution.
4) Two-photon machining system based on SLM (spatial light modulator) : As shown in Figure (f), traditional two-photon machining is point-scanning and direct-writing, and the processing efficiency is generally not high.The use of SLM (such as DMD, LC-SLM) high throughput, flexible light field control ability, can dynamically generate any “digital mask” pattern in real time,1 to achieve high efficiency, high precision projection processing, in order to achieve the purpose of improving processing efficiency.