Apr 18

“How few photons can the human eye perceive?”

On April 13, our student chapter was very pleased to welcome OSA traveling lecturer Prof. Malvin Carl Teich, professor emeritus at Boston University and Columbia University. He is well known for his seminal book “Fundamentals of Photonics”, co-authored by Bahaa E. A. Saleh. We were very impressed by his curriculum vitae that includes everything from fractal stochastic processes to the study of the information transmission in biological systems.

After a quick welcome at the institute, the officers of the student chapter proceeded to have a common lunch in a Franconian restaurant with Prof. Teich. We had a very relaxed discussion with him that lead us to the question what such a distinguished scientist thinks that could be of future interest in physics or science in general. We were very intrigued by his answer: “I would like to see quantum physics and biology grow closer together.”

Back at the Max Planck Institute for the Science of Light, Prof. Teich had a chance to visit the labs of all three divisions of the Max Planck Institute in Erlangen.  The dialogue with the local PhD students included discussions on the progress of single photon emitters in the form of quantum dots and whispering gallery mode resonators, quantum communication systems in the mid-IR regime, as well as dye lasers used for the interaction with single molecules. In addition, some time was scheduled for Prof. Teich to discuss with two of our three directors.

In the evening, Prof. Teich held a lecture entitled “How Few Photons Can the Human Eye Perceive?” We were very curious for an answer to this both fundamental and scientifically very interesting question. And certainly, Prof. Teich did not disappoint, showing the historic series of experiments – some even ranging back several decades – that tried to provide a definitive answer to this question. In the end he and his coworkers came to the conclusion that the number of photons the human eye can perceive strongly depends on the observer. The final number may range from just a few photons to up to hundreds of them, depending on the level of confidence of the observer of actually having observed the dim flash of light.

His enjoyable presentation attracted an audience of about 80 people and triggered many questions and interesting discussions. We have received a lot of positive feedback about his lecture from the attendees. The lecture was followed by a buffet. This was the perfect occasion for students to talk to Prof. Teich and come in contact with other fellow students. During the event we advertised our student chapter and encouraged students to join and support our work.

The hbar OMEGA OSA student chapter Erlangen is very grateful for the opportunities provided by the OSA to have world class scientists visit us and to have the chance to interact with them on a personal level. We would like to extend our sincere congratulations to the OSA for its centennial celebration and hope for many more years of great optical science to come.