DYE LASER: INTRODUCTION CONSTRUCTION MECHANISM ADVANTAGES & DISADVANTAGES APPLICATIONS

1. ORGANIC DYE LASERS
By: AMIRAH BINTI BASIR
SIF170004
MODERN OPTICS & LASER PHYSICS (SIF2020)
PROF DR. OOI CHONG HENG
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2. OUTCOMES
- INTRODUCTION
- CONSTRUCTION
- MECHANISM
- ADVANTAGES & DISADVANTAGES
- APPLICATIONS
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3. INTRODUCTION
USES ORGANIC DYE AS LASING MEDIUM, USUALLY LIQUID
FORM
DYE HAVE VERY BROAD EMISSION AND GAIN SPECTRUMS
SOME OF ORGANIC DYES : RHODAMINE 6G, FLUORESCENT
COUMARIN
IT IS TUNABLE – USE BIREFRINGENT GRATING TO PRODUCE
A SPECIFIC WAVELENGTH
3 MAIN TYPES : PULSED DYE LASER, CONTINUOUS WAVE
DYE LASER, MODE-LOCKED DYE LASER
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4. WHY
ORGANIC
DYE
LASER???
AT EXCITATION WAVELENGTH, DYE HAVE STRONG ABSORPTION AND
AT LASING WAVELENGTH HAVE MINIMAL ABSORPTION. MINIMUM
OVERLAP BETWEEN ABSORPTION AND EMISSION SPECTRA
HIGH QUANTUM YIELD (0.5-1)
GOOD PHOTOCHEMICAL STABILITY
A SHORT FLUORESCEENCE LIFETIME (5-10ns)
LOW ABSORPTION IN THE FIRST EXCITED STATE AT THE PUMPING AND
LASING WAVELENGTH
LOW PROBABILITY OF INTERSYSTEM CROSSING TO THE TRIPLET STATE
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5. DYE SPECTRAL EMISSION CHARACTERISTICS
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6. CONSTRUCTION
MAJOR REQUIRED COMPONENTS
• ACTIVE/LASING MEDIUM
• PUMPING SOURCE
• RESONATOR
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7. ACTIVE MEDIUM
> LIQUID MATERIAL
ORGANIC DYE
+
WATER, BENZENE,
ALCOHOL E.T.C
PUMPING
SOURCE
> NEED ENERGY TO
EXCITE THE DYE
> FLASH LAMPS AND
SEVERAL TYPES OF
LASER IS USED
> ACTUALLY A
SOURCE OF PHOTONS
RESONATOR
> MIRRORS
> FOR TUNING -
REPLACE ONE OF THE
MIRRORS WITH
BIREFRINGENT
DIFFRACTION GRATING
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8. CONFIGURATION 1
- DYE IS PUMPED THROUGH
THE CAPILLARY TUBE FROM
STORAGE TANK
- FLASH LAMP OPTICALLY
EXCITE THE DYE WHILE IN
CAPILLARY TUBE
- THE OUTPUT OF THE LASER
PASSES THROUGH BREWSTER
WINDOW TO THE OUTPUT
COUPLER
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9. CONFIGURATION 2
- DYE IS PUMPED THROUGH
NOZZLE AT HIGH SPEED TO
FORM BREWSTER ANGLE
JET STREAM
- THE EXCITATION
MECHANISM : SECOND
LASER (Eg: ARGON LASER)
- THE LASER BEAM
REFLECTED FROM TWO
HIGH REFLECTIVE MIRRORS
TO THE OUTPUT COUPLER
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10. MECHANISM
PUMP LIGHT SOURCE EXCITES THE DYE MOLECULES TO EXCITED SINGLET
STATE
THE DYE MOLECULES EMIT LIGHT VIA FLUORESCENCE, AND BECOME
TRANSPARENT TO THE LASING WAVELENGTH
WITHIN MICROSECOND, MOLECULES CHANGE TO THEIR TRIPLET STATE –
PHOSPHORESCENCE LIGHT EMITTED
MOLECULES ABSORB THE LASING WAVELENGTH, DYE BECOME OPAQUE
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11. 3 MAIN TYPES
OF ORGANIC
DYE LASER
• PUMPED BY OTHER LASERS (EXCIMER, NITROGEN OR
FREQUENCY-MULTIPLIED Nd:YAG LASER)
• 2MW dye laser pumped by Nitrogen laser
PULSED DYE LASER
• PUMPED BY A CONTINUOUS WAVE LASER (EG: Ar
LASER)
• CW dye laser with 5W Ar ion laser
CONTINUOUS WAVE DYE LASER
• PRODUCE VERY SHORT PULSES WHEN USING
DIPERSIVE PRISM / GRATINGS IN CAVITY
MODE-LOCKED (SHORT PULSE) DYE LASER
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12. • ADVANTAGES
• SMALL BEAM DIAMETER
• LESS BEAM DIVERGENCE
• HIGH OUTPUT POWER
• NOT SO COMPLEX
CONSTRUCTION
• GOOD EFFICIENCY
• DISADVANTAGES
• HIGH COST – NEED TO INSERT
GRATINGS
• NEED OTHER LASER BEAMS
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13. APPLICATION
S
RESEARCH TOOL
• LASER-INDUCED
FLUORESCENCE (LIF)
• TUNABLE DYE LASER
OSCILLATOR-AMPLIFIER
MEDICINE
• OPTICAL FIBRE CATHERER
• PULSED DYE LASER
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14. APPLICATIONS IN RESEARCH TOOLS
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LASER-INDUCED
FLUORESCENCE (LIF) :
COMBINATION OF DYE LASER
AND NITROGEN LASER
-> analytical tool used in
combustion research
laboratories for sensitive,
spatially resolved detection of
minor species
TUNABLE DYE LASER
OSCILLATOR-AMPLIFIER :
DYE LASER PUMPED BY
COPPER VAPOR LASER
–> applied in atomic vapour
laser isotope separation
(ALVIS)

15. APPLICATIONS IN MEDICINE
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PULSED DYE LASER TREATMENT
–> bright light is used to
destroy the abnormal blood
vessels under the skin, number
of pulses in a treatment
depend on the size of the
birthmark / malignancies
OPTICAL FIBRE CATHERER :
Laser angioplasty with pulsed
dye laser and integral ball-tiped
optical fibres
-> shatter kidney stones or gall
stones

16. SUMMARY
• USES ORGANIC DYE AS ACTIVE MEDIUM
• PRODUCE WIDE WAVELENGTH OUTPUT LASER
(VISIBLE, ULTRAVIOLET AND NEAR INFRARED
SPECTRUM)
• ALSO KNOWN AS TUNABLE LASER
• HAVE MORE ADVANTAGES THAN DISADVANTAGES
• USEFUL IN MANY APPLICATIONS
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17. REFERENCES
• https://en.wikipedia.org/wiki/Dye_laser#Construction
• https://www.ias.ac.in/article/fulltext/reso/015/09/0804-0818
• https://www.daenotes.com/electronics/microwave-radar/dye-
laser
• https://www.colby.edu/chemistry/PChem/lab/DyeLaser.pdf
• https://www.youtube.com/watch?v=TYHVWQNdod0
• https://www.slideshare.net/search/slideshow?searchfrom=he
ader&q=dye+laser
• Silfvast, W.T., Laser Fundamentals, 1996, Cambridge University
Press
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18. Thank You
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