School of Physics & Astronomy, University of St Andrews

Malcolm Dunn, Bruce Sinclair, Peter Lindsay and Aly Gillies developed this material a few years back and decided that it is now time to "get it out there". We have tried to make the software accurate. However, as this was primarily developed as a teaching package, sometimes rigor has been sacrificed to make a clearer illustration of the point, or to allow the calculations to be "do-able" within a sensible timescale. We hope you enjoy the software. Comments and constructive criticism always welcome at : psst@st-andrews.ac.uk.

Explore the science of lasers and nonlinear optics with our interactive educational simulations

Updates and errata

Second Update May 2010: I've had word (and then experienced it myself) that Win7 64bit (and therefore presumably other 64-bit versions of Windows) cannot install the Psst! Software. Seems the 32bit installer will not run at all! To circumvent this I have zipped up the install set. You should unzip the file - best in c:\program files\psst!, then you need to register the four ocx files contained therein. Then run the command prompt (cmd.exe) as Administrator. The "as Administrator" is important otherwise they will not register. This is easily done by typing cmd into the "Search programs and files" box on the Start menu, then when CMD appears you should right-click it and chooise "Run as Administrator". In this command window then type: "cd c:\program files\psst!" [Press return], then to register the four OCX files type: "regsvr32.exe softbttn.ocx" [Press return], "regsvr32.exe dialobj.ocx" [Press return], "regsvr32.exe comdlg32.ocx" [Press return], "regsvr32.exe comctl32.ocx" [Press return]. Remember not to put the inverted commas around the commands! Give it a whirl and let me know how you get on. Cheers - Aly. p.s. I bundled the contents of the vista-patch.zip and the VBv5 runtime dll in the too to simplify the process. Not as slick as a proper installer, but functional I think.

Update May 2010: Not unexpectedly the same issue with the Psst! teaching package that was experienced in Windows Vista is still present in Windows 7. The solution is the same for Vista however i.e. please download the vista-patch.zip and follow the instructions in the Psst! Vista text file it contains. There are additional problems with the two applications that require Visual Basic (v5). You will need to make sure that you have the VB5 runtime dll. Get this from Microsoft. From this file copy msvbvm50.dll to the Psst! installation folder (c:\program files\psst!). You will also need to register two OCX files that fail to register on install (softbttn.ocx & dialobj.ocx). To do this you should copy these from the c:\Windows\system32 folder into the Psst! installation folder. Then run the command prompt (cmd.exe) as Administrator. The "as Administrator" is important otherwise they will not register. This is easily done by typing cmd into the "Search programs and files" box on the Start menu, then when CMD appears you should right-click it and chooise "Run as Administrator". In this command window then type: "cd c:\program files\psst!" [Press return], then to register the two OCX files type: "regsvr32.exe softbttn.ocx" [Press return], "regsvr32.exe dialobj.ocx" [Press return]. Please don't put the inverted commas around the commands! I think that covers it. Let me know if otherwise. Cheers - Aly.

Update Jan 2008: It has come to our attention that the Psst! teaching package does not behave well under Windows Vista. In particular the links to launch applications from the teaching material do not work. This is a result of changes to the Windows Help system under Windows Vista. I have made a patch file to remedy the problem. You should unzip the vista-patch.zip file into the Psst! installation folder - replacing Psst.exe and placing a copy of the WinXP Help engine in the folder. Download vista-patch.zip here. The launcher program (Psst.exe) should then use the old WinXP help file to launch the teaching material (in photonics.hlp).

Update Sept 2004: A request was made to extend the wavelength range from 150-11000nm. This has been implimented in version 2.0.1.2 of las_cav.exe. Back-up your old las_cav.exe and replace it with the latest version to eliminate the bug.

Errata 2: The recent files list did not actually open the recent file when clicked. This has been addressed. Back-up your old las_cav.exe and replace it with the latest version to eliminate the bug.

Errata 1: A bug in the Laser Resonator program (las_cav.exe) has been detected and fixed. This bug meant that 2 duct cavities were calculated incorrectly when Duct 1 was to the left of Duct 2. Back-up your old las_cav.exe and replace it with the latest version to eliminate the bug.
Updated version of las_cav.exe @ 2 September 2004 (this is not the full Psst! package - the link for the package download is toward the bottom of the page)

Click on the simulation title in the image below to go to a screen shot and a short description of the simulation.

The Psst! simulations provide students and educators with a powerful tool for exploring the theory and practice of laser amplifiers, laser oscillators, optical cavities, and second order (c⁽²⁾) nonlinear optics. Some of the features and benefits of this resource are:-

• The simulations allow students to change various parameters to answer "what if" questions.
• Guided exploration of the simulations gives a much better "feel" for what the relevant science and equations mean, using rapidly-calculated (often real-time) graphical displays.
• Some simulations solve problems that cannot be done fully analytically, such as laser spiking.
• No programming required by students, example parameter sets can be saved and retrieved.
• Intuitive operation of simulations, with similar interface throughout.
• Enormous scope for interaction and exploration through changing parameters.
• As the simulations are based on analytical or numerical solutions of the underlying physical equations, they allow exploration and understanding of "non-standard" issues (to within specified approximations).
• Teaching material on the disc guides students in their investigations.

Download
Please feel free to download and use out Psst! software. Psst! stands for Photonics Simulation Software for Teaching. Click that last link to download a zip file. Expand this and run the setup.exe file enclosed. There is a README file in there that will tell you what is about to happen to your system on installation. Have fun and learn deep.

p.s. The splash-screens seemed like a good idea at the time, but some may find the short delay until they disappear to be frustrating (living life at too quick a pace I guess?). Anyway, the splash screens can be dismissed immediately by clicking them.

This software remains the property of the authors and must not be sold or passed on without their express permission.The software is distributed as-is and no form of contract is implied or obligation undertaken.