Course Info | Class Notes | Evaluation / Check Marks | Labs | Class Schedule & Homework |
Course Description
This is a practical course which examines the operating principles & procedures, maintenance, and applications of specific laser systems. Power sources, laser structure, cavity optics, basic laser processes, beam characteristics, and emission spectra for a selection of key commercial and research lasers including ion, CO2, excimer, YAG, ruby, and dye types will be examined. Specifics of wavelength selection (for multi-line lasers), pulse generation (including Q-switching and modelocking), and non-linear optics (harmonic generation and OPO) are included as well as applications for these techniques are examined. Safety issues (e.g. laser classes and interlock requirements) will also be covered. A laboratory component allows students to investigate the operational principles and several key applications of practical laser systems.
The output of our Innova-90 argon laser is seen here. Using multi-line optics several wavelengths lase simultaneously. The output beam is then split by a diffraction grating to reveal all the spectral components. As tube current is increased gradually more lines begin to appear - in this case the current is relatively low (< 20A) so only five lines are lasing. Clearly visible are the 488 blue and 514 green lines. This laser is used to demonstrate Mode structures (TEMxx), wavelength selection, quantum principles (such as competition for energy levels), and ion laser hardware. In multi-line, multi-mode operation it can produce seven watts of blue-green laser light.
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This course is offered as part of the Photonics Engineering Technician (2 year) and Technology (3 year) Programs at Niagara College.
Check your Registration Status, Marks, and Lab Group Assignments here
Fundamentals of Light Sources and Lasers by Csele, 2004, John Wiley & Sons, ISBN 0-471-47660-9
Chapters 6 through 15 are covered in this course.
Specific Elements Of This Course
Laboratory components to accompany this material are also outlined on this page
Students will use a Crystal Technologies AO Modulator in the laboratory to examine both Bragg and Raman-Nath regimes. Here a HeNe beam is diffracted by the modulator.
Week #1 (2010/01/11):
Introduction
Entrance Examination (Wed, Jan 13, in class)
HeNe lasers: role of each gas, levels and transitions, IR line suppression (how and why)
Homework: review the "HeNe Laser - Case Study" document
Week #2 (2010/01/18):
Lab (both groups on Friday) Safety Introduction
Finish HeNe quantum - situations with shared ULL and shared LLL
HeNe power supplies
Ion Lasers: energy levels and transitions, ion tube construction
References: Csele chapter 9 and Hecht on ion lasers (read this)
Homework: Complete the safety quiz on blackboard
Complete the prelab for lab #1 (Read the "SPINTRO" document)
Read Hecht on Ion Lasers
Week #3 (2010/01/25):
The Safety Quiz must be completed before the lab this week
Lab #1 this week
Ion lasers: magnetic field, gas ballast/replenishment
Ion laser power supplies
Cavity optics, wavelength selection, longitudinal modes
Homework: read "Ion Lasers - A Summary" document
Week #4 (2010/02/01):
Lab #1 this week
Single-line operation, wavelength selection
Longitudinal modes, use of etalons
Cavity configurations and stability, calculating radius of curvature
Homework: complete the prelab for lab #2
Week #5 (2010/02/08):
Lab #2 this week, Lab #1 DUE this week
CO2 lasers: role of gases, energy levels and transitions, Optics
Homework: Read Chapter 11, Review HeNe and Ion material for midterm
Week #6 (2010/02/15):
Lab #2 this week
E/P ratio for gases
Low-pressure CO2 laser design (continued)
Review for Midterm #1
Homework: STUDY !!!!
Week #7 (2010/02/22):
Lab #3 this week, Lab #2 DUE this week (Fri)
Midterm #1 in Class on Tuesday
Midterm handed-back, reviewed in class (Wed)
High-pressure (TEA) CO2 laser design, preionizer, discharge circuitry
Week #8 (2010/03/01):
March Break - No Classes
Week #9 (2010/03/08):
Lab #3 this week
Finish TEA laser design - thyratron and spark-gap switches
UV Gas Lasers: Excimer and N2
Excimer - Gas mixes, quantum details
Nitrogen lasers - quantum, level lifetimes, Fast (Blumlein) design
Week #10 (2010/03/15):
Lab #4 this week, Lab #3 DUE this week (Fri)
Solid State Lasers: Pump Sources, Wavelength stability issues
Week #11 (2010/03/22):
Lab #4 this week
Q-Switching (Methods)
Q-Switching (AO - diffraction types, EO - halfwave voltages)
Q-Switching (AO and EO devices)
Review for Midterm #2 (Thursday)
Homework: STUDY !!!!
Week #12 (2010/03/29):
Lab #4 DUE this week (THURSDAY)
Q-Switching (EO - %T calcualtions, gain computations)
Q-Switching (Minimum holdoff required)
First Pulse suppression
Midterm #2 in Class on Thursday
Week #13 (2010/04/05):
Lab #5 this week
Review Midterm #2
Cavity Dumping and Modelocking
Non-Linear / SHG (principles)
Non-Linear (coefficients, magnitudes)
Week #14 (2010/04/12):
Lab #5 this week
Non-Linear materials (and damage threshold calculations)
Week #15 (2010/04/19):
Lab #5 DUE this week
Final Exam Review
Final Exam Review SOLUTIONS selected solutions (not all) to practice questions for the final exam.Students in 2010W will complete five laboratory assignments, each two-weeks in length. Lab sections are split into smaller groups (A and B) which perform different parts of the lab alternatively.
A penalty of 50% is levied for an absence during a lab period. All labs are due one week after they are completed in the laboratory by or at the time of the beginning of the lab period after which they are considered late and penalized at the rate of 10% per day (i.e. the 'day' late begins at the beginning of the lab).
Safety Refresher and Lab Introduction
A lab introduction in which students will view a safety video and be provided with a demonstration of specific hazards and procedures in Niagara College's high-power laser lab (V15). Specific topics reviewed include laser classes, exposure limits, nominal hazard zones, calculating OD and selecting safety glasses, high voltage safety, chemical and fire safety. At the conclusion of the session students must write a quiz.
This session is MANDATORY and students must attend the session and write the quiz in order to be provided access to the lab.
Lab Session during the week of 2010/01/18
Lab #1: Ion lasers
A look at both the power supplies and optical characteristics of an ion laser. Using the Coherent Innova-90 argon laser in V15 students will examine the various lines of an argon laser and relative output powers of each. Using wavelength-selective optics the threshold currents of argon laser lines will be examined. As well, the use of current and light regulation modes will be examined in the lab. Next, students will investigate the high-current circuitry of a Supergraphite CR-6 argon laser power supply. In this lab, reduced three-phase voltages will be used to allow investigation of circuits within the supply without the dangers normally associated therein.
Lab Sessions:
Group A - Part A during the week of 2010/01/25, Part B during the week of 2010/02/01
Group B - Part B during the week of 2010/01/25, Part A during the week of 2010/02/01
All groups DUE during the week of 2010/02/08
Lab Marking Scheme can be found in the lab itself.
Lab #2: Cavity Alignment
Complete alignment of the optics of two types of lasers will be completed. First, the optics on a large-bore MPB IN-100 carbon-dioxide laser will be aligned using a coaxial HeNe laser beam. Burn patterns will then be used to analyze beam structure under optimized and non-optimal conditions. Next, the optics (HR, OC, and Fold Mirrors) on a Coherent argon-ion laser-pumped dye laser will be removed and aligned by using the fluorescence of the dye itself to provide alignment 'spots'. A lab report will outline details of the procedure.
Lab Sessions:
Group A - Part A during the week of 2010/02/08, Part B during the week of 2010/02/15
Group B - Part B during the week of 2010/02/08, Part A during the week of 2010/02/15
All groups DUE during the week of 2010/02/22
Lab #3: Pulsed Gas Lasers
Students will mix various gas fills for a Lumonics Excimer 500 and a Lumonics TEA-203 CO2 laser in V15 and will study the effect on power output. In the excimer laser, a Helium-Nitrogen mixture will be employed with various concentrations of nitrogen (the active lasing species) and the effect of nitrogen concentration on output power noted. In the TEA laser pressure and voltage will be varied. Results will be correlated with the calculated E/P ratio of the gases employed.
Lab Sessions:
Group A - Part A during the week of 2010/02/22, Part B during the week of 2010/03/08
Group B - Part B during the week of 2010/02/22, Part A during the week of 2010/03/08
All groups DUE during the week of 2010/03/15
No Lab on Week of March Break
Lab #4: DPSS Lasers
Using an argon-laser pumped titanium-sapphire (Ti:Saph) laser, a vanadate laser will be pumped and the effect of pumping at various wavelengths examined. This unique "Laser-pumped-laser-pumped-laser" arrangement allows a regular DPSS laser to be pumped by a tunable IR source allowing investigation of the sensitivity of vanadate to pumping wavelength.
Lab Sessions:
Group A - Part A during the week of 2010/03/15, Part B during the week of 2010/03/22
Group B - Part B during the week of 2010/03/15, Part A during the week of 2010/03/22
All groups DUE on THURSDAY 2010/04/01 in class
No Lab on Good Friday
Lab #5: Q-Switched Lasers
A Diode-Pumped Lee YAG Laser employing an AO Q-switch will be examined with the effect of pulse rate on output determined. In order to demonstrate how an AOM works and ways in which it may be used an external AOM will be aligned for Bragg diffraction, with the effective intra-cavity loss determined, and an AOM modified for use as a PCAOM will be used to separate the multiple wavelength (RGB) output of a 'white light' HeCd laser.
Lab Sessions:
Group A - Part A during the week of 2010/04/05, Part B during the week of 2010/04/12
Group B - Part B during the week of 2010/04/05, Part A during the week of 2010/04/12
All groups DUE during the week of 2010/04/19
The lab schedule is subject to change based on availability of laboratory equipment
For this course ...
Professor Mark Csele
Office: L-17 (Office hours are POSTED on the EL panel on the door)
Telephone: (905) 735-2211 x.7629
E-Mail: (Be sure to include 'Lasers' in the subject line to avoid deletion by an anti-spam filter)
URL:
http://technology.niagarac.on.ca/people/mcsele
Copyright (C) Mark Csele and Niagara College, Canada, 2005-2010
Some images and text are published in Fundamentals of Light Sources and Lasers by Csele, Wiley (2004), ISBN 0-471-47660-9 and hence are Copyright (C) John Wiley and Sons. Further reproduction in any form is prohibited without written approval from the publisher.