SBIR Phase I: Inexpensive, low-power, pressure-sensing multi-touch input devices for flexible displays

这个小型企业创新研究(SBIR)第一阶段项目将解决生产全功能多点触控压力传感屏幕所需的核心硬件和软件问题，方法是在电子纸显示器后面放置一个基于内插力敏感电阻(IFSR)的传感器。与其他目前可用的多点触控解决方案相比，IFSR具有显著的优势。这些特性包括低成本、低功耗、原生多点触控功能、从任何对象或指示笔感知触摸的能力、灵活性和外形可伸缩性。由于其扁平的外形因素和压力传感能力，IFSR传感器可以安装在薄的平板显示器后面，为基于电子墨水的大小设备提供商业上可行的多点触控输入解决方案。本项目的研究包括五个部分：1)电子墨水显示器、IFSR传感器和电路板的分层和集成；2)定制设计的全集成单传感器驱动芯片，以取代当前的模拟多路复用器、两个移位寄存器和两个缓冲器；3)开发和实现高效的传感器扫描算法，以实现微安培功耗；4)研究和测试CPU高效技术，用于实时识别手指或触针的功能触摸，以及拒绝手掌和其他非功能触摸。这项创新直接解决了现有多点触控解决方案在应用于电子纸显示器时面临的挑战，包括成本、功耗、感知手指和触控笔的能力，以及缺乏背光，这阻碍了屏幕上的传感技术。如果成功，由此产生的设计和技术将填补技术空白，使现有的巨大电子书阅读设备市场无法实现多点触控输入。由于这一结果可以很容易地推广到具有其他类型柔性显示器(尤其是OLED屏幕)的设备，它们有可能为薄型、负担得起的多点触控输入显示器开辟一个全新的市场空间，使零售、商业、工业和公共部门的最终用户受益。

This Small Business Innovation Research (SBIR) Phase I project will address the core hardware and software issues necessary to yield a fully functioning multi-touch pressure-sensing screen by putting an Interpolating Force-Sensitive Resistance (IFSR) based sensor behind an electronic paper display. IFSR has significant advantages over other currently-available multi-touch solutions. These include low cost, low power consumption, native multi-touch capacity, the ability to sense touches from any object or stylus, flexibility and form-factor scalability. Because of its flat form factor and pressure sensing ability, an IFSR sensor can be mounted behind a thin, flat display, providing a commercially viable multi-touch input solution for large and small e-ink based devices. The research for this project includes five components: 1) layering and integration of an e-ink display, IFSR sensor, and circuit board; 2) custom design of a fully-integrated single sensor driver chip to replace the current analog multiplexer, two shift registers, and two buffers; 3) development and implementation of an efficient sensor scanning algorithm to enable micro-Ampere power consumption; 4) research and testing of CPU-efficient techniques for real-time identification of functional touches by fingers or styli, and rejection of palms and other non-functional touches. This innovation directly addresses the challenges faced by existing multi-touch solutions when applied to electronic paper displays, including cost, power consumption, ability to sense both fingers and styli, and the lack of backlighting, which hinders above-screen sensing technologies. If successful, the resulting design and techniques will fill the technical gap that denies multi-touch input from the large existing market of e-book reader devices. Since the results can easily be generalized to devices with other types of flexible displays (notably OLED screens) they have the potential to open up a whole new market space for thin, affordable, multi-touch input displays benefiting retail, commercial, industrial, and public-sector end users.