This invention belongs to the field of spectroscopic technology for
sample composition and content analysis, specifically relating to a device and method for measuring the concentration of specific elements based on
fiber Bragg gratings and LIBS. A
solid-state Q-switched
laser emits pulsed light that interacts with the substance through an
optical path. The resulting
plasma is transmitted to corresponding single-mode fibers, circulators, and corresponding gratings, then returns to the
circulator and is fed into the corresponding
detector. A timing controller controls the
light intensity collected by the
detector for integration calculation, and the result is returned to a computer. The wavelengths selected by the first and second
fiber Bragg gratings correspond to the
internal standard element and the
analyte element in the sample, respectively. Using the ratio of the corresponding light intensities and the
mathematical relationship established with the standard sample, the concentration of the
analyte element in the unknown sample can be calculated. This invention eliminates the need for a complex
spectrometer structure, resulting in a simple device structure,
high resolution for single-element concentration measurement, and allows for control of the
fiber Bragg
grating wavelength within 100 pm using a temperature-controlled water bath, or the measurement of different element concentrations by replacing the
fiber Bragg grating with different wavelengths.