A micro-nano structure similar to the thorns on the surface of a cactus is produced by three-dimensional light curing. The micro-nano structure can simulate the hydrophobic characteristics. These micro-nano structures have great application value in the field of biomimetic materials. But if we look closely, the detailed structure is actually layered. In our 3D printing process, each layer grows upwards, and the area underneath will be a little larger, so as it grows upwards, it will gradually decrease. In the process of reduction, this step is formed.
This step is actually not consistent with our real situation, which means that it has a problem of spatial resolution. But directly use a similar beam to generate this structure. This laser pointer light beam can be cured during the transmission process in the exposed medium, and the 3D structure is directly formed in this process, because the light beam travels very fast. Therefore, the three-dimensional structure can be produced at the same time in a moment.
A cover article in a top optical journal, it produces a spirally transmitted light beam. Then this light beam is actually somewhat similar to ours. We are just making a characterization, which does not mean that it can definitely have this correspondence. But we can try similar work. So I really did this work when I had a groundbreaking article published in a scientific journal in 2012.
A simple ring beam is used. The ring beam has a spiral phase distribution. If the spiral phase distribution interferes with spherical waves and plane waves, it will have some relatively complex light field distributions. After the intermediate and spherical waves interfere, there will be a spiral light intensity distribution. Then the spiral light intensity distribution is irradiated on the light-cured material to produce such a cone-shaped structure.
If you look closely at this cone-shaped structure, there is green laser pointer still a spiral inside. In other words, this material has actually recorded the spatial structure of our light. It can also be said that our light directly printed this material like this A structure. This job is actually very simple light distribution, but they made the first attempt. So if we consider the situation of more complicated beam distribution, then further exploration may produce more results and more application scenarios.