Femtosecond laser writing of infrared microlens arrays on chalcogenide glass

Sulfur-based glasses have gradually developed into a new generation of infrared optical materials with high transmittance in the mid-and long-infrared wavelengths. As2Se3, as a representative chalcogenide glass in the mid-infrared band, is commonly prepared for some infrared optical devices. In this paper, we prepare infrared microlens arrays with an area of 0.64 mm2 by femtosecond laser technology on As2Se3. In terms of morphology, the surface of the prepared microlens array has excellent morphology and smoothness. The uniform IR microlens array achieves high transparency of up to 60 % in the mid-infrared region. And there is no significant change in transmittance before and after laser processing, which has outstanding application prospects. In terms of the size of the lens, we can control the diameter and depth of microlens by adjusting the laser power and the number of pulses. In infrared imaging, the lateral magnification of the lens can be adjusted by controlling the focal length of the lens so that the size and clarity of the letter F can be controlled. The cross-sectional intensity distribution of the focusing spots was calculated, which demonstrates the superior uniformity of our microlenses.

Automated summary

In this paper, infrared microlens arrays with an area of 0.64 mm2 were prepared on As2Se3 using femtosecond laser technology. The prepared microlens array showed excellent surface morphology and smoothness. The uniform IR microlens array achieved high transparency of up to 60% in the mid-infrared region, with no significant change in transmittance before and after laser processing, showing outstanding application prospects.