About the Book

Students in physical and life science, and in engineering, need to know about the physics and biology of light. From Photon to Neuron is the first textbook to address these students’ needs in a modern way.

The only prerequisite for the main text is first-year undergraduate physics and corresponding math. Supplementary sections make the book also suitable as the basis of a graduate-level course.

Dozens of exercises are included at all levels of complexity, many involving computer work. Full solutions are available to adopters.

The book is available from Princeton University Press. The Contents, "To the Student," and "To the Instructor" are freely available here as well as Chapter 1. There is an e-book edition, available for Kindle or via Google Play.

A Chinese language translation is available: 从光子到神经元:光、成像、视觉.

Three additional chapters are now freely available online in preliminary form.


In the twenty–first century, it has become increasingly clear that the quantum nature of light is essential both for the latest imaging modalities and even to advance our knowledge of fundamental life processes, such as photosynthesis and human vision.

From Photon to Neuron places the modern synthesis of wave and particle aspects of light front and center, then uses it both to develop quantum physics and to give a unified view of a wide range of optical and biological phenomena. Along the way, the book builds the needed background in neuroscience, photochemistry, and other disciplines, bringing students from their first–year physics courses to the ongoing revolutions in optogenetics and superresolution microscopy. Other topics include fluorescence and two–photon imaging, as well as Förster resonance energy transfer, all with an eye to what these indispensable techniques teach us about their physical underpinnings.

With its integrated approach, From Photon to Neuron can be used as the basis for interdisciplinary courses in biophysics, sensory neuroscience, the physical foundations of laboratory instrumentation, biophotonics, bioengineering, or nanotechnology. Throughout, the goal is for students to gain the fluency they need to derive every result for themselves. To that end, the text includes exercises at all levels of complexity, including many that guide students through computer-based solutions. Supplementary online materials include experimental data for use in working these exercises.

Readers will acquire several research skills that are often not addressed in traditional courses:

These basic skills, which are relevant to nearly any field of science or engineering, are presented in the context of case studies from living systems, including:

Here are slides from a talk about the book at the 2016 AAPT national meeting.

Intended Audience

Who takes this class?

At my institution, the students are undergraduates who have taken one year of university physics. No background in computer programming, and no Biology or Chemistry prerequisite courses are assumed. However, each chapter has a ”Track 2” appendix with more advanced material; with these sections and some assigned primary research articles, the book can also serve a graduate–level course.

Although the book is not about medicine per se, many students who take the course at Penn are premedical, in part because the course addresses many of the competencies that form the basis of the new MCAT2015 (see the Instructor’s Preface and the 2015 MCAT guide).

The book has almost no overlap with my previous books Biological Physics and Physical Models of Living Systems. Biological Physics focused on molecular mechanics, fluid mechanics, molecular machines, and neural signaling. Physical Models of Living Systems focused more on intracellular control systems, and on general background skills. From Photon to Neuron focuses on quantum physics and its application to imaging, neural readout and control, and human vision.

Instructor Resources

All of the graphics are freely available in a form suitable for classroom use here. Additional Instructor Resources, including solutions to the problems both in Python and in MATLAB and ideas for classroom demonstrations, are available from the publisher.

Student Resources

Student resources, including online experimental datasets, suggestions on the “Your Turn” questions, and videos, are available on the Student Resources Page.

Samples and Ordering Information

ISBN information for Photon to Neuron: ISBN-13: 9780691175195

If you’d like sample materials, please contact Ingrid Gnerlich at Princeton University Press.

Responses to From Photon to Neuron:

“As elegant as it is deep. A masterful tour of the science of light and vision, it goes beyond artificial boundaries between disciplines and presents all aspects of light as it appears in physics, chemistry, biology and the neural sciences.... In the same way that the author instructs non-physics students in some basic physics concepts and tools, he also provides physicists with accessible and very clear presentations of many biological phenomena involving light.... One of the most insightful, cross-disciplinary texts I have read in many years. It is mesmerising and will become a landmark in rigorous, but highly accessible interdisciplinary literature.”

Luis Alvarez-Gaumé, Stony Brook University, in CERN Courier

From Photon to Neuron: Light, Imaging, Vision completes a trilogy begun by Biological Physics and Physical Models of Living Systems. Those works establish Nelson as the preeminent author of textbooks at the intersection of physics and biology.... Nelson uses words, pictures, formulas, and code to teach students how to construct models and interpret data. His books provide a master class in how to integrate those four different approaches into a complete learning experience.”

Brad Roth, Oakland University, in Physics Today magazine

“A thorough and sweeping tour from the fundamental physics of light to the neurobiology of the retina.... Lavishly illustrated and carefully explained.”

Sönke Johnsen, Biology, Duke University, in American Journal of Physics

“Nelson has taken a subject usually treated in depth only at the graduate level and developed an understandable and coherent treatment appropriate for undergraduates. He provides a unified framework with which to discuss the disparate ways biological systems interact with light and the variety of ways researchers use light as a biological probe. There is no serious competitor for this book.”

Alex J. Levine, Chemistry+Biochemistry, University of California, Los Angeles

“The science of light and vision transcends the artificial boundaries between physics, chemistry, and biology. Isaac Newton appreciated this. Phil Nelson does, too. Nelson masterfully blends the natural sciences to explore how we perceive and control light.”

Adam Cohen, Chemistry+Physics, Harvard University

“Intriguing, useful, and interdisciplinary. Nelson’s excellent book provides students with a comprehensive introduction to the interaction between light and biosystems.”

Zhong-Can Ou-Yang, Institute of Theoretical Physics, Chinese Academy of Sciences

“This unusual book covers a huge variety of topics on light and vision, from fundamental physics to human visual psychophysics to some of the latest optical-microscopy techniques. Students and researchers alike in the physical and life sciences will find the book fascinating.”

King-Wai Yau, Johns Hopkins University School of Medicine

“Engaging and unique. This is an excellent and well-developed textbook on the physics of light as it is processed by biological organisms and on how light can be used to interrogate biological material. From Photon to Neuron is poised to become a standard text for both physicists and biologists.”

Stephanie Palmer, Organismal Biology and Anatomy, University of Chicago