Wang Shicong, Wendt Amy E, Boffard John B, Lin Chun C
Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Rev Sci Instrum. 2015 Jan;86(1):013111. doi: 10.1063/1.4906290.
Widely available, small form-factor, fiber-coupled spectrometers typically have a minimum exposure time measured in milliseconds, and thus cannot be used directly for time-resolved measurements at the microsecond level. Spectroscopy at these faster time scales is typically done with an intensified charge coupled device (CCD) system where the image intensifier acts as a "fast" electronic shutter for the slower CCD array. In this paper, we describe simple modifications to a commercially available chopper wheel system to allow it to be used as a "fast" mechanical shutter for gating a fiber-coupled spectrometer to achieve microsecond-scale time-resolved optical measurements of a periodically pulsed light source. With the chopper wheel synchronized to the pulsing of the light source, the time resolution can be set to a small fraction of the pulse period by using a chopper wheel with narrow slots separated by wide spokes. Different methods of synchronizing the chopper wheel and pulsing of the light sources are explored. The capability of the chopper wheel system is illustrated with time-resolved measurements of pulsed plasmas.
广泛使用的小型光纤耦合光谱仪通常具有以毫秒为单位测量的最短曝光时间，因此不能直接用于微秒级别的时间分辨测量。在这些更快的时间尺度上进行光谱分析通常使用增强型电荷耦合器件（CCD）系统，其中图像增强器充当较慢的CCD阵列的“快速”电子快门。在本文中，我们描述了对市售斩光轮系统的简单修改，使其能够用作“快速”机械快门，用于控制光纤耦合光谱仪，以实现对周期性脉冲光源的微秒级时间分辨光学测量。通过将斩光轮与光源的脉冲同步，可以使用具有由宽辐条隔开的窄槽的斩光轮，将时间分辨率设置为脉冲周期的一小部分。探索了斩光轮与光源脉冲同步的不同方法。通过对脉冲等离子体的时间分辨测量来说明斩光轮系统的能力。
