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

2. OUTLINE
• Introduction
• history
• Objectives
• working principle
• Instrumental design
• overview of LIBS process
• Advantages
• Limatations

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

4. History
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

5. OBJECTIVES

6. Principle
 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. Instrumentation design
• LIBS system consist of:
• Laser :Nd : YAG ,and Eximer .
• Spectrometer : either a monochromator /a polychromator
• Fiber optics
• Detector :PMT /CCD (respectively to the spectroeter
used) attached to a spectrograph analyzes the collected
plasma light and this is coupled to a pc which can raidly
process and interpret the acquired data

8. Overview of LIBS Process

9. Advantages OF LIBS
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. LIMITATIONS
 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
 Possibilty of ocular damage by the high energy laser
pulses

11. THANK YOU