PaMIr: Phase Modulation Interferometry (resubmission)

PaMIr：相位调制干涉测量（重新提交）

• 批准号: ST/S000178/1
• 负责人: Armin Reichold
• 金额: $ 46.55万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FS000178%2F1
• 关键词: PaMIr; Phase; Modulation; Interferometry; resubmission

Distances are one of the most fundamental properties that humanity uses to describe the world and has learned to measure in an amazing variety of ways using everything from the length of your forearm to the wavelengths of photons or even electrons or atoms.In modern industrial societies length measurements are deeply embedded into all production processes and the requirements for range, resolution, speed and absolute accuracy are constantly growing. In modern production machines such as CNC mills or lathes these measurements have to be performed not only with micrometer resolution but in these machines there are dozens of distances that have to be measured rapidly and simultaneous while they are also changing at high speeds of meters per second. The University of Oxford has developed a technology called Frequency Scanning Interferometry (FSI) capable of measuring absolute distances with high accuracy (better than half a micrometer per meter) and high time resolution of 2.7 million measurements per second. This technology is being successfully commercialised with an industrial partner (Etalon AG) and has found many applications in industry and science. The current commercially available state of FSI is however not yet capable of measuring fast moving targets in a continuous form. The group of Prof Reichold at the University of Oxford has recently developed a novel method for rapid distance measurements of fast moving targets referred to as Phase Modulation Interferometry (PaMIr). In the PaMIr technique the laser light used in the measurement interferometers is phase modulated at high frequencies and the resulting interference signal is demodulated multiple times at different frequencies. From the resultant signals it is possible to reconstruct the change in length of measurement interferometer. The PaMIr method is in principle backward compatible with the instrumentation used for FSI measurements and will maintain the unique feature of FSI such as simultaneous measurements of many distances and a low cost per measurement channel. This compatibility allows a measurement to start at an absolute distance measured with FSI which can then be tracked at high speed with the PaMIr method.The PaMIr project aims to develop the basic PaMIr principles to a state ready for implementation in a commercial instrument in a collaboration with Etalon and VadaTech. To do so we will have to analyse the rapid flow of data from each PaMIr measurement interferometer with complex algorithms in an on-line way with a latency below 0.1 milliseconds as needed for applications in modern production machines. The PaMIr instrument will have to simultaneously digitise all interferometer signals at a rate 125 million samples per second and feed these data streams into fast parallel processing units based on Field Programmable Gate Arrays (FPGAs). We will program these FPGAs to apply the PaMIr algorithms to all channels in parallel with low latency which is a formidable task. To do this efficiently and in a commercially applicable way we need to know and control the hardware of the DAQ system at all levels which is why Oxford has teamed up with a world leading manufacturer of data acquisition equipment (VadaTech). Together with VadaTech and Etalon we have already developed a first optical readout system for FSI. We will build on this development and further improve its performance to meet the PaMIr requirements. Ultimately we expect to license the PaMIr technology to Etalon AG to make the technique commercially available for industrial and scientific application alike and to license the firmware we develop to VadaTech to allow the use of their DAQ systems as multi-channel digital lock-in amplifiers or PLL and PID controllers.

距离是人类用来描述世界的最基本的属性之一，人类已经学会了以各种各样的方式测量，从前臂的长度到光子的波长，甚至电子或原子的波长。在现代工业社会中，长度测量深深嵌入到所有生产过程中，对范围，分辨率，速度和绝对精度的要求不断提高。在现代生产机器如CNC米尔斯或车床中，这些测量不仅必须以微米分辨率进行，而且在这些机器中，必须快速和同时测量数十个距离，同时它们也以每秒米的高速变化。牛津大学开发了一种称为频率扫描干涉测量法（FSI）的技术，能够以高精度（优于每米半微米）和每秒270万次测量的高时间分辨率测量绝对距离。这项技术正在与工业合作伙伴（Etalon AG）成功地商业化，并在工业和科学领域得到了许多应用。然而，目前市售的FSI状态还不能以连续的形式测量快速移动的目标。牛津大学的Reichold教授团队最近开发了一种新方法，用于快速移动目标的快速距离测量，称为相位调制干涉术（PaMIr）。在PaMIr技术中，在测量干涉仪中使用的激光在高频下被相位调制，并且所产生的干涉信号在不同频率下被多次解调。从所得到的信号中，可以重建测量干涉仪的长度变化。原则上，PaMIr方法与用于FSI测量的仪器向后兼容，并且将保持FSI的独特特征，例如多个距离的同时测量和每个测量通道的低成本。这种兼容性使得测量可以从FSI测量的绝对距离开始，然后可以用PaMIr方法高速跟踪。PaMIr项目旨在与Etalon和VadaTech合作，将PaMIr的基本原理发展到可以在商业仪器中实施的状态。为此，我们必须使用复杂的算法在线分析来自每个PaMIr测量干涉仪的快速数据流，延迟低于0.1毫秒，以满足现代生产机器的应用需求。PaMIr仪器必须以每秒1.25亿个样本的速度同时数字化所有干涉仪信号，并将这些数据流馈送到基于现场可编程门阵列（FPGA）的快速并行处理单元中。我们将对这些FPGA进行编程，以将PaMIr算法应用于所有并行通道，同时降低延迟，这是一项艰巨的任务。为了有效地并以商业适用的方式做到这一点，我们需要了解和控制各个层面的DAQ系统的硬件，这就是为什么牛津大学与世界领先的数据采集设备制造商（VadaTech）合作。我们已经与VadaTech和Etalon一起开发了第一个用于FSI的光学读出系统。我们将在此基础上进一步改进其性能，以满足PaMIr的要求。最终，我们希望将PaMIr技术授权给Etalon AG，使该技术可用于工业和科学应用，并将我们开发的固件授权给VadaTech，以允许将其DAQ系统用作多通道数字锁定放大器或PLL和PID控制器。