1. Highly Efficient Broadband Achromatic Microlens Design Based on Low-Dispersion Materials
- Author
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Xueqian Wang, Chuanbao Liu, Feilou Wang, Weijia Luo, Chengdong Tao, Yuxuan Hou, Lijie Qiao, Ji Zhou, Jingbo Sun, and Yang Bai
- Subjects
Broadband achromatic focusing ,Metamaterials ,Low dispersion materials ,Visible wavelength ,Microlenses ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Metalenses with achromatic performance offer a new opportunity for high-quality imaging with an ultra-compact configuration; however, they suffer from complex fabrication processes and low focusing efficiency. In this study, we propose an efficient design method for achromatic microlenses on a wavelength scale using materials with low dispersion, an adequately designed convex surface, and a thickness profile distribution. By taking into account the absolute chromatic aberration, relative focal length shift (FLS), and numerical aperture (NA), microlens with a certain focal length can be realized through our realized map of geometric features. Accordingly, the designed achromatic microlenses with low-dispersion fused silica were fabricated using a focused ion beam, and precise surface profiles were obtained. The fabricated microlenses exhibited a high average focusing efficiency of 65% at visible wavelengths of 410–680 nm and excellent achromatic capability via white light imaging. Moreover, the design exhibited the advantages of being polarization-insensitive and near-diffraction-limited. These results demonstrate the effectiveness of our proposed achromatic microlens design approach, which expands the prospects of miniaturized optics such as virtual and augmented reality, ultracompact microscopes, and biological endoscopy.
- Published
- 2024
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