Some home-grown software
There follows a selection of small programs written by Aly Gillies using Delphi.
- Zoom lens (260KB)
This program was developed for use alongside a laboratory practical where the students
actually experiment with lens systems. It allows the user to experiment with image
formation in a (up-to) 3 lens system. It also allows examination of a varifocal and zoom
lens system. An accompanying help file (16KB)gives basic
information on how to use the program. This is a 16-bit application, so can be used in
either Win 3.1x or Win95/98/NT.
- Bohr Atom (218KB)
This program illustrates the oscillations of a Bohr atom. The user chooses the quantum
level and the wavefunction is displayed and animated. This is a 32-bit application so can
only be used under Win 95/98/NT.
- Phasor (217KB)
This program shows a rotating vector and draws out the connection between this and
sinusoidal motion.. This is a 32-bit application so can only be used under Win 95/98/NT.
- Interference (311KB)
This program compares two and six beams interference. Hopefully illustrating the origin of
the different interference patterns. If you double click on the graph then all lines are
drawn double thickness. This gives the application increased visibility on a data
projector.
- Vectors (257KB)
This application shows two vectors oscillating along the x and y axes. The resultant
vector is shown also. The user can vary the amplitude of the x and y vectors, and also
alter phase shift between the them. The application can then be used to illustrate modes
of polarisation. If you double click on the graph then all lines are drawn double
thickness. This gives the application increased visibility on a data projector.
We do not expect anything untoward to result from the use of these programs, but we
advise that you use them at your own risk.
CUPS worksheets
The Consortium For Upper-level Physics
Software have produced a number of excellent simulation. We use these in a number of
courses including teaching optics in first year and quantum mechanics in third year. The
third year QM use is in the form of a hands-on computational session which replaces four
lecture slots with half the class attending two sets of two PC-classroom based sessions.
In the first session we introduce the software's ability to perform one-dimensional bound
state solutions, and give the students written work to hand in, based on choosing two
exercises from a pool of four on these bound state problems. In the second PC-classroom
session we introduce stationary scattering states in one dimension and again ask the
students to undertake one exercise from a choice of three. All of these exercises are
based on information drawn and adapted from the CUPS Quantum Mechanics manual. The
culmination of this is for the students to work in groups on a project concerning electron
states in a 1D lattice. [Please take note of the solvable problem in CUPS, associated with
a bug in Turbo Pascal on machines running at > ~200MHz. Find information on this at the
foot of this page]
Contemporary Laboratory Exercises in Astronomy (CLEA)
worksheets
We use the CLEA software for teaching in our first year astronomy lab. The students use
the software to make observations and the worksheets guide them through the
derivation of information from their observations.
The CLEA software was developed by the Department of Physics at the Gettysburg College
and is available to download from the their web-site.
The CTI Physics publication Computers in Physics Education No.18 (Dec 1999)
carries a review of the CLEA software.
Photonic Simulation Software for Teaching (Psst!)
A group in the School has developed a suite of simulations that are useful in teaching
basic concepts from image formation in geometric and gaussian optics to coupled wave
equation and 3-level laser simulation. This material is used within the School for
teaching at various levels. This software is now available commercially through the laser
teaching company OptoSci. A demo
version of the entire Psst! suite is available on their web site.
Turbo Pascal Bug in CUPS, PAS Waves Interference, etc.
Borland: Runtime Error 200 - 'Divide by 0'
Applications that use the CRT unit may generate this error message when running on very
fast machines (i.e. Pentium Pro 180 and above). The cause of this error is a timing loop
that occurs as part of the initialization of the CRT unit. This timing loop counts how
many clock ticks occur within the loop and then that number is divided by 55. The result
of this division is a value that is too large to fit into an integer value. The 'Divide by
0' error message is the catch-all error that is displayed when this overflow occurs.
There are currently no Borland endorsed patches for this problem. There are several
user provided patches available on the internet that patch both the CRT unit as well as
existing EXE files. The easiest way to obtain these patches is to go to www.altavista.digital.com and search on '+
bp7patch.zip + tppatch.zip' without the quotes.
These patches are not endorsed or supported by Borland and are used at your own
risk.
St Andrews action
At the University of St Andrews we have patched our CUPS and PAS Wave Interference
executables using a patch obtained via searching the web as described above. This has
cured the problem and we are happily running all CUPS applications (site licence) and the
PAS Wave Interference (single copy) these apps. in our PC classroom on PIII 700MHz
machines under NT4.
Diclaimer: The patches are not endorsed or supported by the University of
St Andrews and are used at your own risk.
08 September 2003