The OpenFlexure Microscope is a 3D-printed, low-cost microscope capable of automated image acquisition through the use of a motorised translation stage and a Raspberry Pi imaging system. This automation has applications in research and healthcare, including in supporting the diagnosis of malaria in low-resource settings. The plasmodium parasites that cause malaria require high magnification imaging, which has a shallow depth of field, necessitating the development of an accurate and precise autofocus procedure. We present methods of identifying the focal plane of the microscope, and procedures for reliably acquiring a stack of focused images on a system affected by backlash and drift. We also present and assess a method to verify the success of autofocus during the scan. The speed, reliability and precision of each method are evaluated, and the limitations discussed in terms of the end users' requirements.

中文翻译：

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在电动显微镜上进行快速、高精度的自动对焦：在 OpenFlexure 显微镜上自动进行血样成像

OpenFlexure 显微镜是一种 3D 打印的低成本显微镜，能够通过使用电动平移台和 Raspberry Pi 成像系统自动采集图像。这种自动化在研究和医疗保健方面有应用，包括支持在资源匮乏地区诊断疟疾。该疟原虫引起疟疾的寄生虫需要高倍率成像，其景深较浅，因此需要开发准确和精确的自动对焦程序。我们介绍了识别显微镜焦平面的方法，以及在受后冲和漂移影响的系统上可靠地获取一组聚焦图像的程序。我们还介绍并评估了一种验证扫描过程中自动对焦成功的方法。评估了每种方法的速度、可靠性和精度，并根据最终用户的要求讨论了局限性。