Femtosecond laser multibeam parallel processing for variable focal-length optofluidic chips.

Optofluidic chips are frequently utilized in applications such as biological observation, chemical detection, dynamic displays, imaging, holography, and sensing. Yet, developing continuously zoomable technology has been challenging in the production of optical devices. Using a spatial light modulator to shape a femtosecond laser to achieve multibeam parallel pulse punching, we propose an easy-to-fabricate, stable, and reliable tuning technique in this Letter. We then propose the addition of a liquid medium with a continuously variable refractive index to achieve controllable zooming without changing the position and morphology of the microlens. By pumping various concentrations of the liquid medium into the optofluidic chip, continuous tunability of the device was experimentally verified.

Spatially modulated femtosecond laser direct ablation-based preparation of ultra-flexible multifunctional copper mesh electrodes and its application.

Multifunctional electrodes possess superior properties such as high photoelectric properties and high stability. Laser manufacturing process is one of the widely used method for electrode fabrication. However, the current multifunctional electrode laser manufacturing process suffers from low fabrication speed. Here, we report a high-efficiency laser digital patterning process to fabricate copper-based flexible transparent conducting electrodes. By using a spatially modulated, one single laser spot is modulated into an array of spots with equal intensity, and the fabrication speed can be improved by more than 20 times over the traditional single pulse processing. In addition, copper mesh electrodes with a high photoelectric property have been fabricated. A transparent touch screen panel and multifunctional windows are fabricated with transparent electrodes to demonstrate their use in vehicle defogging, portable heating, and wearable devices.