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1. Elemental Analysis of spinach &
Using LIBS
Supervisor
Dr. Zubair Khan Niazi
Co-Supervisor
Sir Imran Rehan
Presented by
Mathilda Samuel

2.  Introduction
 history
 Objectives
 working principle
 Instrumental design
 overview of LIBS process
 Advantages
 Limitations

3. A spectrochemical technique which utilizes an
intense laser pulse to determine the
atomic/elemental composition of a sample via
generation of a high-temperature micro plasma
followed by time resolved optical spectroscopy.

4. 1960
Maiman, first ruby
laser
1962
Brech, Cross; Birth
of
LIBS: detection of
spectrum from ruby
laser induced
plasma
1965
Zel’dovich, Raizer,
First theoretical
model for laser
breakdown of a gas
1964
Runger et al. First
direct spectrochemical analysis by
LIBS

6.  ND-YAG laser fall on the sample.
 In a laser requires an understanding of the energy
transition phenomena in the atoms of its active medium.
 They include: spontaneous emission, stimulated
emission/absorption and non-radiative decay.

7.  LIBS system consist of:
 Laser :Nd : YAG ,and Eximer .
 Spectrometer : either a monochromator /a polychromator
 Fiber optics
 Detector :PMT /CCD (respectively to the spectrometer used)
attached to a spectrograph analyzes the collected plasma light
and this is coupled to a pc which can rapidly process and
interpret the acquired data

9. Advantages
 offers rapid analysis
 requires no sample preparation
 sensitive to all elements
 scalable in sample size
 requires no contact with the sample
 work in hostile environments

10.  Increased cost and complexity
 Large interference effects( in the case of LIBS in aerosols, the
potential interference of particle size).
 Detection limits are generally not as good as established solution
techniques.
 poor precision
 Possibility of ocular damage by the high energy laser pulses