Encapsulated bio‐carbon soot film for measuring nano‐size beam diameter of low power lasers

Abstract

Abstract Nano‐scale laser beam size and its shape information are essential parameters in most optics‐based precision measurements and nano‐scale material processing. It is also quite challenging to measure nano‐size optical beams accurately for both open experiments and at compact workplace of microscope due to various instrumental factors. Outside of the visible spectrum, usually wavelength‐sensitive fluorescence markers and composite materials are used to read the laser beam profile. In this article, a cost‐effective carbon nano‐particles (CNPs) film has been developed from candle soot. Furthermore, the developed bio‐carbon soot film is encapsulated with optically transparent composite polymer on aqueous media to measure sub‐micron size spot of a low‐power laser. Field emission scanning electron microscopy, optical spectrum analysis, Fourier transform infrared spectroscopy, UV‐visible spectroscopy, differential scanning calorimetry and thermogravimetric analysis techniques have been performed to characterize the developed CNPs film and optimized its functionality. The fabricated film has been used to measure sub‐micron laser beam size. Due to the wide absorption spectrum of the developed bio‐CNPs film, the sensitivity region for measurement lies within both visible and beyond the visible spectrum.

Keywords

• bio‐carbon nano‐particles
• candle soot
• laser beam diameter
• laser marking
• low power laser
• sub‐micron laser spot