Hussein Haitham M, Terra Osama, Hussein Hatem, Medhat Mohamed
Appl Opt. 2020 Jul 20;59(21):6417-6423. doi: 10.1364/AO.393852.
Electronic distance meters (EDMs) are widely used in different applications, such as surveying and civil engineering. In order to calibrate an EDM, different techniques can be used, including displacement interferometers and reference baselines. In this paper, an indoor baseline is designed and then accurately measured using femtosecond laser pulses from an optical frequency comb to be used for EDM calibration. The baseline consists of 13 fixed bases that cover 58 m distance. In order to accurately measure the distances between the bases, autocorrelation between femtosecond laser pulses is employed. The measurement shows a maximum precision of 14 µm over the 13 bases. Although this deviation is dominated mainly by the placement of the target mirror, the system capability is much more sufficient to safely calibrate the best available commercial EDM. The stability of the baseline is also investigated by measuring the interbase distances over long periods of time.
电子测距仪（EDM）广泛应用于不同领域，如测量和土木工程。为了校准电子测距仪，可以使用不同的技术，包括位移干涉仪和参考基线。在本文中，设计了一个室内基线，然后使用来自光学频率梳的飞秒激光脉冲对其进行精确测量，以用于电子测距仪校准。该基线由13个固定基座组成，覆盖58米的距离。为了精确测量基座之间的距离，采用了飞秒激光脉冲之间的自相关技术。测量结果表明，在13个基座上的最大精度为14微米。尽管这种偏差主要由目标镜的放置所主导，但该系统的能力足以安全校准现有的最佳商用电子测距仪。还通过长时间测量基座间的距离来研究基线的稳定性。
