Effect of lens-to-sample distance on spatial uniformity and emission spectrum of flflat-top laser-induced plasma

	Effect of lens-to-sample distance on spatial uniformity and emission spectrum of flflat-top laser-induced plasma
	Fu Hongbo; Wang Huadong; Zhang Mengyang; Wu Bian; Zhang Zhirong
刊名	PLASMA SCIENCE & TECHNOLOGY
	2022
卷号	24
关键词	laser-induced plasma lens-to-sample distance plasma image RSD laser-induced breakdown spectroscopy
ISSN号	1009-0630
英文摘要	The optimal spectral excitation and acquisition scheme is explored by studying the effect of the lensto-sample distance(LTSD) on the spatial homogeneity and emission spectra of flflat-top laser converging spot induced plasma. The energy distribution characteristics before and after the convergence of the laser beam with quasi flflat-top intensity profifile used in this study are theoretically simulated and experimentally measured. For an aspheric converging mirror with a focal length of 100 mm, the LTSD(106 mm≥LTSD≥96 mm) was changed by raising the stainless-steel sample height. The plasma images acquired by ICCD show that there is air breakdown when the sample is below the focal point, and a ring-like plasma is produced when the sample is above the focal point. When the sample is located near the focal point, the plasma shape resembles a hemisphere. Since the spectral acquisition region is confifined to the plasma core and the image contains all the optical information of the plasma, it has a lower relative standard deviation(RSD) than the spectral lines. When the sample surface is slightly higher than the focal plane of the lens, the converging spot has a quasi flflat-top distribution, the spatial distribution of the plasma is more uniform, and the spectral signal is more stable. Simultaneously, there is little difference between the RSD of the plasma image and the laser energy. In order to further improve the stability of the spectral signal, it is necessary to expand the spectral acquisition area.
语种	英语
内容类型	期刊论文
源URL	[http://ir.hfcas.ac.cn:8080/handle/334002/133194]
专题	中国科学院合肥物质科学研究院
作者单位	中国科学院安徽光学精密机械研究所
推荐引用方式 GB/T 7714	Fu Hongbo,Wang Huadong,Zhang Mengyang,et al. Effect of lens-to-sample distance on spatial uniformity and emission spectrum of flflat-top laser-induced plasma[J]. PLASMA SCIENCE & TECHNOLOGY,2022,24.
APA	Fu Hongbo,Wang Huadong,Zhang Mengyang,Wu Bian,&Zhang Zhirong.(2022).Effect of lens-to-sample distance on spatial uniformity and emission spectrum of flflat-top laser-induced plasma.PLASMA SCIENCE & TECHNOLOGY,24.
MLA	Fu Hongbo,et al."Effect of lens-to-sample distance on spatial uniformity and emission spectrum of flflat-top laser-induced plasma".PLASMA SCIENCE & TECHNOLOGY 24(2022).