Emily Page 1 Emily Whittington received a B.A. with Honors in Physics from Austin College in May of 1997. A brief description of her project is given below. Emily is now a graduate student in Optical Sciences at the University of Arizona in Tucson. She is shown above with the open-frame laser used in her project. For stable operation, gas lasers such as the Helium-Neon laser used in this experiment require a standing electromagnetic wave in the laser cavity in both the longitudinal and transverse directions.
Longitudinal modes lead to several closely spaced wavelengths in the output beam of a laser.
These modes are not visible to the unaided eye, but can be detected with a laser spectrum analyzer. On the other hand, transverse modes can be seen. Emily's project involved study of the conditions required for producing particular transverse modes, and construction of an extra-cavity mode converter for converting modes with rectangular symmetry into modes with cylindrical symmetry. To see some of her experimental results, go to the next page.