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Bending stress analysis of flexible touch panel

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Abstract

Flexible touch panel is required to undertake extensive bending operations during service; thus, bending testing of flexible touch panel for mechanical behaviors and even reliability is crucial for realizing the technology. This study aims at exploring the bending behaviors of a flexible touch panel under a four-point bending test using finite element analysis. The touch panel is a laminated structure composed of seven thin film layers, namely a polyester layer, an adhesive layer, a polyimide layer, two organic layers and two indium tin oxide conductive layers. Because the touch panel structure is symmetry, only a quarter of the flexible touch panel is established in the analysis model. The mechanical properties of the materials are first obtained using both nanoindentation and uniaxial tensile/compressive testing. Furthermore, a modeling technique based on global and local finite element analysis is applied to evaluate the bending stress at a specified radius of curvature. Special emphasis of the calculation is put on the critical region with respect to stress, which is identified as the most susceptible cracking site.

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Acknowledgments

This work was supported by the cooperative project between the Industrial Technology Research Institute and National Tsing Hua University.

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Authors and Affiliations

  1. Department of Power Mechanical Engineering, National Tsing Hua University, 101, Sec. 2, Kuang Fu Road, Hsinchu, 30013, Taiwan

    Meng-Kao Yeh, Li-Yu Chang & Min-Ru Lu

  2. Department of Aerospace and Systems Engineering, Feng Chia University, 100, Wen Hwa Road, Taichung, 407, Taiwan

    Hsien-Chie Cheng

  3. Display Technology Center, Industrial Technology Research Institute, 195, Sec. 4, Chung Hsing Road, Chutung, 31040, Taiwan

    Pi-Hsien Wang

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  1. Meng-Kao Yeh
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  2. Li-Yu Chang
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  3. Min-Ru Lu
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  4. Hsien-Chie Cheng
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  5. Pi-Hsien Wang
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Correspondence to Meng-Kao Yeh.

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Yeh, MK., Chang, LY., Lu, MR. et al. Bending stress analysis of flexible touch panel. Microsyst Technol 20, 1641–1646 (2014). https://doi.org/10.1007/s00542-014-2200-1

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  • DOI: https://doi.org/10.1007/s00542-014-2200-1

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