(2018 Winter)

Prerequisites for this course include PHTN1300 Principles of Light Sources and Lasers. This course is required for entry into PHTN1400.

This course is a prerequisite for PHTN1306 in the fall term. Failure to pass either the theory or lab/practical portion of this course will result in ineligibility to progress to this course in the fall term.

Three midterm examinations, valued at 20% each, as follows ...

- Safe use of lasers (NHZ, laser classes and regulations, OD calculations abnd choosing safety glasses)
- Quantum mechanics of shared levels
- Resonators, modes (FSR), cavity optics, wavelength selection methods, etalon usage
- All material from lab 1A and 1B
- Chapters 3-5 (all background from PHTN1300), 6, 9, 11
- Solid-State lasers (up to and including basic re-absorption loss calculations but not Q-switching)
- SS Lasers: Pumping techniques (flashlamps/arc/diode), Wavelength stability of diode pump sources
- SS Lasers: Thermoelectric Cooling
- Calculating the required OD of safety glasses and choosing the correct glasses based on safety criteria
- Calculating mirror reflectivities for wavelength selection (Review from PHTN1300)
- Selecting cavity mirror radii for stability based on g-parameters
- Calculating number of longitudinal modes in a gas laser (using Doppler formula) and solid-state laser (using λ-to-f conversion). Includes FSR calculations for cavities.
- Selecting an etalon (calculating thickness) for single-frequency operation
- Calculation of expected output power using the simple model with both a homogeneous and inhomogeneous medium (different formulae). Includes calculation of saturation power from parameters such as λ, σ, τ, and amplifier diameter
- Calculating re-absorption loss (γ
_{thermal}) in units of m^{-1}and use in fomulating gain threshold and output power calculations

- Safe use of lasers (choosing safety glasses based on OD)
- Solid State Lasers: Thermalization of LLLs and Gain calculations
- Describe the process of Q-Switching (e.g. how N
_{ull}builds, effect of rate, etc) - Describe the principles of an AO and EO modulator
- Explain what Bragg angle is and how DE and IL are computed
- Describe the process of modelocking and why a broad amplification medium is required
- All material from labs #2 and #3 (Review all questions at the end of these labs including prelabs)
- Calculating the required OD of safety glasses and choosing the correct glasses based on safety criteria
- Calculating operating temperature of a diode laser based on wavelength required (or emission wavelength at a given temperature). Includes interpreting datasheets.
- Calculating small-signal gain given output power (and including re-absorption loss γ
_{thermal}) - Calculating Output Power of a laser including re-absorption loss (some overlap to midterm #1)
- Calculate the holdoff required of Q-Switches for a given laser
- Calculate the transmission of an EO modulator for an applied voltage (and vice versa)
- For an AOM/PCAOM, compute Bragg angle and DE
- Calculate the Q-switch rate for a modelocked laser for a given cavity (longitudinal and ring)
- Calculate the expected bandwidth given the length of a pulse (and vice-versa)

- Safe use of lasers (choosing safety glasses based on OD)
- CW Gas laser power supplies and tube design (HeNe & Ion, Basic Electronics, Tube structure, Maintenance, Gas Issues)
- CO
_{2}lasers, low-pressure design only (Electronics, IR optics, role of gases, including material from various presentations) - Everything in "Non-Linear / Harmonic Generation", "CO2 Lasers Low Pressure", "E/P Ratio", and "Pulsed Gas Lasers" documents
- Safe use of lasers (choosing safety glasses based on OD)
- Calculate the efficiency of a harmonic generator for a given material and given applied irradiance
- Determine suitability of a non-linear material based on damage thresholds
- Calculate wavelengths produced by non-linear processes (including n-wave mixing and OPO)
- TEA and Excimer lasers (including circuit design, discharge dynamics, E/P ratio)
- E/P ratio in gases (including material from the presentation and labs)
- All material from lab #5
- Everything in "E/P Ratio", "CO2 Lasers - TEA", "Pulsed Gas Lasers" notes
- Calculating optimal gas fill for excimer and CO2 lasers based on E/P ratio

Labs and assignments combined for a total of 40%

Course policies follow the Standardized Policies and Procedures for CEE (dated January 2011). In summary:

- LATE assignments are worth ZERO. There is no "grace period" with a "per day" penalty. Late submissions (i.e. ANY not printed and ready when you enter the lab) receive a mark of zero. You will be DENIED access to the printer at the start of the lab - either the lab is ready to submit, or it is late and hence worth zero.
- Students are allowed only ONE single late submission without penalty. This is a once-only extension until 8:30 am the following business day ... once used, any further late submission will receive an automatic zero.
- Students must pass the theory (testing) and practical (lab/assignment) portions of the course separately in order to receive a passing grade. If a failing grade is received in either portion, then the lower of the two marks (theory or practical) will become the final grade.
- In order to be considered for supplementary evaluation (SE) upon failure in this course, a mark of 50% minimum will be required in the practical (lab/assignment) portion of the course plus a mark of 45% minimum in the theory (testing) portion. A theory mark of 44% or less, or a lab mark of 49% or less, will result in failure with no SE option.
- Granting of an SE is not automatic nor it is a right - it is a special consideration granted by the associate dean for those with extenuating circumstances only (and not just a "second chance"). Those qualifying for an SE must apply to the associate dean who will evaluate those circumstances and if accepted will arrange for the SE (since staff must be assigned to deliver the SE). Consideration will be made based on individual circumstances and attendance will be considered. The process for an SE is explained in the T&LP.
- Devices capable of RF reception are specifically
__banned__during all examinations and tests. This includes cell phones (which are not permitted, whether turned on or not) as well as tablets and laptops. Scientific calculators must not have RF capability (i.e. the use of a cell phone, tablet, or laptop as a calculator is expressly forbidden even if the "wireless" function is switched off). Translational references and dictionaries must be in paper form, not on an electronic device.

Complete course policies can be found in the Teaching and Learning Plan (T&LP) document found on Blackboard.

There are two textbooks in this course. These same texts were used last term in PHTN1300 and will be used in the third year in PHTN1306 (i.e. you will not have to purchase another text for PHTN1306).

__Fundamentals of Light Sources and Lasers__ by Csele, 2004, John Wiley & Sons, ISBN 0-471-47660-9

Chapters 5 to 14 are covered in this course.

__Laser Modeling: A Numerical Approach with Algebra and Calculus__ by Csele, 2014, CRC Press, ISBN 9781466582507

Chapters 3, and 5 are covered in this course.

**ERRATA:** In __Laser Modeling__, in unity-gain equations (2.1), (2.6), and (2.8) the correct terms are e^{gx} not e^{-gx}. Gain is always a positive quantity, attenuation is negative.

- Standard Operating Procedures (SOPs) for lasers in Niagara College's high powered laser labs.
- Laser Safety For Students from the in-class presentation.
- Coherent.Com where you may download and view the laser safety video required before the first lab. Also available on YouTube. Watching this video, and writing a quiz BEFORE the first lab is MANDATORY!
- Cavity Optics covering longitudinal modes, linewidth, saturation, and use of etalons. Applies to all lasers including gas and solid-state lasers.
- Pass By Pass Model as required for lab #1B from the in-class presentation. Follows section 3.9 of
__Laser Modeling__. - Ion Lasers - A Summary from a Spectra-Physics manual. A good overall review of lasers in general including longitudinal modes and resonant cavities.
- A links for lab #1B on
__CO2 LASERS__:- Sam's Laser FAQ on Homebuilt CO2 Lasers including discussions on optics

- Solid State Lasers from the in-class presentation. (Password protected PDF).
- A Review of Pre-Requisite Material from PHTN1300 for Solid-State Lasers, Q-Switching, and Term Test #1 ...
**Laser Gain**from the in-class presentation (the__most important__concept from last term!) (Password-protected PDF).*Contains an example question about Q-Switch holdoff which is an excellent introduction to Q-Switching.***Cross-Sections and Gain**from the in-class presentation (the__second__most important concept from last term!) (Password-protected PDF).*Contains an example question pertaining to computation of inversions and thermalization of the LLL.***Thermal Populations and Gain**(Password-protected PDF).*A complete example on computing thermalization of the LLL and gain. Excellent study material for TERM TEST #1.*

- Temperature Control 101 covering thermoelectric temperature controllers as employed in the lab (Password protected PDF)
- Midterm #1 Preparation Questions A selection of example questions from previous midterm examinations as covered in class (some solutions done in review class as time permits). Password protected PDF file.
- Term Test #1 Formula Sheet print this and have it handy while completing the above questions while studying.
- Q-Switching (Password protected PDF)
- Ultrafast Lasers (Password protected PDF)
- Harmonic Generation Password protected PDF file.
- Midterm #2 Preparation Questions A selection of example questions from previous midterm examinations as covered in class (some solutions done in review class as time permits). Password protected PDF file.
- Term Test #2 Formula Sheet print this and have it handy while completing the above questions while studying.
- CO2 Lasers - Low Pressure primarily covering quantum mechanisms of the CO2 laser as well as design of CW lasers.
- E/P Ratio covering design issues with nitrogen, excimer, and CO
_{2}gas lasers. - E/P Graph allowing determination of the E/P ratio for nitrogen gas.
- Pulsed Gas Lasers covering E/P issues, preionization, and discharge circuit design for TEA, Excimer, and N
_{2}lasers. - Midterm #3 Preparation Questions A selection of example questions from previous midterm examinations as covered in class (some solutions done in review class as time permits). Password protected PDF file.

Students in 2018W will complete several laboratory assignments each one or two weeks in length. Lab sections are split into smaller groups (A and B) which perform different parts of the lab alternatively.

**ALL students will perform a lab EVERY WEEK**

NOTE: You will __NOT__ be permitted into the lab and will be __marked absent__ unless BOTH PARTS of the safety quiz on Blackboard has been successfully completed by **Tuesday 2018/01/23 at 8:30 am**.

The absolute, Blackboard-enforced, deadline for successful completion of the entire two-part safety quiz is Monday, 2018/01/22 at 3:00 pm. After that an immediate 5% penalty is applied. Do this early as NO compensation will be given for lack of availability of a website, computer error, or any other excuses.

Before attempting the actual quiz (which is time-limited and must be completed once started), print the required documents from Blackboard and complete the sample safety quiz on blackboard as it will demonstrate the type of calculations required for the actual quiz. If you cannot complete those calculations correctly, remedial action is required on your part prior to attempting the quiz as you are limited in the number of attempts before a severe penalty is applied.

Well before Monday the 22nd, do the following ...

- PRINT the three-page safety glass specs from BLACKBOARD
- VIEW the required safety video from Coherent
- WRITE the First Part of the quiz which concerns regulations. A minimum mark of 14/15 is required and only two attempts are allowed
- REVIEW the safety glass OD calculations from lecture notes then WRITE the Sample Quiz on BLACKBOARD to ensure you understand how it is done
- WRITE the Second Part of the quiz which concerns OD calculations. A minimum mark of 5/6 is required and only two attempts are allowed

Both lab groups will attend this lab on the week of 2018/01/22

Lab Weighting: 1.0

BOTH Lab groups (A & B) will perform the lab on Tuesday 2018/01/30

Successful completion of the two-part Safety Quiz on

Lab report is DUE for both groups on Thursday, 2018/02/08 at the beginning of the lecture, 11:30 am sharp

Lab Weighting: 1.0

Assignment is DUE for both groups on Thursday, 2018/02/15 at the beginning of the lecture, 11:30 am sharp

A complete overview of DPSS design concepts including the thermal and optical characteristics of pump diodes, optical absorption characteristics of vanadate (Nd:YVO

Lab Weighting: 2.0

Lab group A will perform part A on the week of 2018/02/12, part B on the week of 2018/02/19

Lab group B will perform part B on the week of 2018/02/12, part A on the week of 2018/02/19

Lab report is DUE on the week of 2018/03/05 (at the beginning of the next lab period).

The operation of AOM devices and Q-Switching is investigated. An external AOM is 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. In addition, a Q-switch will be aligned on a real flashlamp-pumped Nd:YAG laser and the gain (and hence holdoff of the switch) determined.

Lab Weighting: 2.0

Lab group A will perform part A on the week of 2018/03/05, part B on the week of 2018/03/12

Lab group B will perform part B on the week of 2018/03/05, part A on the week of 2018/03/12

Lab report is DUE on the week of 2018/03/19 (at the beginning of the next lab period).

Students will use a Tsunami femtosecond modelocked laser, aligning the laser for proper modelocking operation including the control of regenerative phase delay, dispersion control in the wavelength selector of the laser, and prevention of CW breakthrough during modelocked operation.

Lab Weighting: 2.0

Lab group A will perform the lab on the week of 2018/03/19

Lab group B will perform the lab on the week of 2018/03/26

Lab report is DUE on the week of 2018/04/02 (at the beginning of the next lab period).

A survey of advanced Q-switching techniques is provided in this lab. The giant first pulse phenomenon is investigated along with the first pulse suppression (FPS) technique in which students will optimize the Q-Switch driver of a commercial DPSS laser.

Lab Weighting: 2.0

Lab group A will perform the lab on the week of 2018/03/26

Lab group B will perform the lab on the week of 2018/03/19

Lab report is DUE on the week of 2018/04/02 (at the beginning of the next lab period).

Lab Weighting: 2.0

Lab group A will perform part A on the week of 2018/04/02, part B on the week of 2018/04/09

Lab group B will perform part B on the week of 2018/04/02, part A on the week of 2018/04/09

Lab report is DUE on the week of 2018/04/16 (at the beginning of the next lab period).

*The lab schedule is subject to change based on availability of laboratory equipment*

*For the Photonics Technician/Technology programs ...*

Professor Mark Csele

Office: V13A (Office hours are

Telephone: (905) 735-2211 x.7629

E-Mail:

URL: http://technology.niagarac.on.ca/staff/mcsele

This course is part of the TECHNOLOGY division

*Some images and text excerpted from Fundamentals of Light Sources and Lasers by Csele, John Wiley & Sons, 2004, ISBN 0-471-47660-9 and hence are Copyright © John Wiley and Sons. Some images and text excerpted from
Laser Modeling: A Numerical Approach with Algebra and Calculus by Csele, CRC Press, 2014, ISBN 9781466582507. Further reproduction in any form is prohibited without written approval from the publishers.*