Encyclopedia … combined with a great Buyer's Guide!

The RP Photonics Encyclopedia

(formerly known as the Encyclopedia of Laser Physics and Technology) is a comprehensive, scientifically robust reference source in the fields of optics and photonics, brought to you by the expert Dr. Rüdiger Paschotta at RP Photonics. It serves the entire global photonics community, encompassing both scholarly researchers and industrial professionals, supporting their work and professional development:

encyclopedia and buyer's guide
  • It also offers a substantial number of valuable tutorials and case studies.
  • It is distinguished by a widely recognized reliable quality concerning the technical and scientific content, balanced focus, good readability, clear navigation structure, and swift server response.
  • It is freely available online (open access, no registration, completely anonymous use with perfect privacy).
  • An early version was available as a two-volume book, published via Wiley-VCH in 2008.
  • Many articles contain useful bibliographies, and each article is permanently accessible through a DOI link. The articles can be cited e.g. in scientific papers.
  • It is connected with the RP Photonics Buyer's Guide and Virtual Exhibition, where one can discover suppliers for a vast array of photonics products and make well-informed purchasing decisions.
  • It has an associated blog, the Photonics Spotlight, which is also available as a newsletter.
  • There are additional resources such as a glossary of photonics terms, articles grouped by categories and a comprehensive and stimulating Photonics Quiz.

An authoritative encyclopedia article on a specific topic often helps a lot to create the essential mental framework before diving into technical details with more specialized papers. Our articles also often help to identify essential papers in an area.

With its unparalleled popularity (receiving around a quarter million page views per month predominantly for its encyclopedia), this influential platform presents a fantastic opportunity for promoting your photonics products! Moreover, there is an opportunity to further engage with the community by becoming a sponsor of our encyclopedia.

Use Ticker



The Photonics Community is Learning Here

Dr. Rüdiger Paschotta, the author of the RP Photonics Encyclopedia
Dr. Rüdiger Paschotta, founder and managing director of RP Photo­nics, has authored all articles of this encyclopedia.

Dr. Rüdiger Paschotta, the expert behind the RP Photonics Encyclopedia, is not only its founder and managing director but also the author of all its articles. His expansive, open-access compendium offers an extensive exploration of optics and photonics, with a host of illustrative examples highlighting the breadth and depth of its content. He is not only mastering a wide range of knowledge in photonics, but also has learned to identify the crucial points and explain things in very helpful ways.

With 1043 articles, his encyclopedia extends far beyond mere definitions typical of dictionaries or glossaries. A significant amount of effort has been for many years, and continues to be, invested to ensure that the information presented mirrors the quality and reliability of an advanced textbook. Numerous references to external resources notable scientific articles and textbooks provide additional resources for further studies.

The consistency and quality of this resource are widely recognized within the field. This refers not only to the technical and scientific content, which serves as an indispensable tool for professional work, but also to its user-friendly design. The website is crafted for effortless reading, clear navigation, and allows for non-intrusive advertising. The clean, well-tested code guarantees a swift response, robust security against hacking threats, and has been honored with an A+ security grade by the Mozilla Observatory, by far outperforming other resources also in that respect.

The encyclopedia is universally accessible via the website, offering full privacy and anonymity to its users, and is frequented by professionals globally in both the photonics industry and scientific research. An earlier version of the encyclopedia was published as a two-volume book by Wiley-VCH in 2008.

In creating this resource, RP Photonics delivers a highly valued service to the global photonics industry and the academic community. This encyclopedia has enriched generations of students and photonics professionals, augmenting their knowledge base with essential facts and context.

Since 2012, the encyclopedia has been seamlessly linked with the RP Photonics Buyer's Guide, a valuable resource for identifying suppliers of optics and photonics products. The fusion of the encyclopedia and buyer's guide optimally supports users in making informed purchasing decisions as no other resource can, and at the same time offers excellent marketing opportunities for photonics products. For the latter, the key aspect is the publication of product information, helping users to generate a short list of suitable suppliers who deserve a closer inspection. In other words, we again generate value by presenting useful supplier information in a huge network of technical and scientific information. This approach works far better for suppliers than “shouting” and spamming, for example.

Dr. Rüdiger Paschotta, the author of the encyclopedia, also offers consulting services in areas such as lasers, fiber amplifiers, nonlinear frequency conversion and fiber optics via RP Photonics. His expertise can be harnessed for development projects or for custom staff training courses conducted on the client's premises. Additionally, he has developed potent simulation and design software for work in laser technology, fiber optics, and thin-film optics.

Since 2012, the encyclopedia has been intimately linked with the RP Photonics Buyer's Guide, a resource for finding suppliers of optics and photonics products. The combination of encyclopedia and buyer's guide is ideal for users making informed purchase decisions, and it also provides excellent opportunities for the marketing of photonics products.

, the author of the encyclopedia, offers a broad range of consulting services in topical areas like lasers, amplifiers, nonlinear optics and fiber optics via RP Photonics. His competence is available for development projects, or for tailored staff training courses performed at the customer's location. Also, he has developed powerful simulation software for work in laser technology, fiber optics and thin-film optics.

Besides the encyclopedia articles, there are related pages, which you can reach via the menu on the top of this page:

Examples of Available Articles in Various Topical Areas

Here you can get an overview of the topics which are covered by this encyclopedia. Note that these are only examples; in total, we have 1043 encyclopedia articles.

  • General optics: geometrical optics, imaging, optical aberrations, entrance and exit pupil, Kramers–Kronig relations, Fourier spectrum, Gaussian beams, Hermite–Gaussian modes, Gouy phase shift, beam quality, brightness, optical resonators, waveguide dispersion, finesse, coherence, phase velocity and group velocity, superluminal transmission and causality, color vision
  • Optical instruments and devices: photo cameras, loupes, microscopes, telescopes, interferometers, Bragg mirrors, beam shapers, optical filters, electro-optic modulators, acousto-optic modulators, optical tweezers, arrayed waveguide gratings, integrating spheres, mode cleaner cavities, Lyot filters, optical spectrum analyzers
the print version of the Encyclopedia of Laser Physics and Technology
In 2008, the encyclopedia appeared at Wiley-VCH as a two-volume book with 555 articles; this book is no longer available. Since then, the online version has been expanded substantially to cover more areas outside laser technology. It is now an optics and photonics encyclopedia.
  • Optoelectronics: photodiodes, avalanche photodiodes, phototransistors, photocathodes, photomultipliers, photon counting, laser diodes, quantum cascade lasers, light-emitting diodes, superluminescent diodes, photonic integrated circuits, silicon photonics, electroabsorption modulators, opto-isolators, image sensors
  • Nonlinear optics: nonlinear crystal materials, intracavity or resonant frequency doubling, sum and difference frequency generation, optical parametric oscillators, parametric generators and amplifiers, Brillouin and Raman scattering, self- and cross-phase modulation, four-wave mixing, quasi-phase matching
  • Fiber optics: high power fiber lasers and amplifiers, Raman amplifiers, single-mode and multimode fibers, rare-earth-doped fibers, double-clad fibers, dispersion-shifted fibers, photonic crystal fibers, fiber Bragg gratings, adiabatic soliton compression, nonlinear polarization rotation
  • Lasers and amplifiers: laser design and development, laser resonators, fiber-coupled diode lasers, diode-pumped lasers, fiber lasers, erbium-doped amplifiers, laser and amplifier noise, power scaling, upconversion lasers, amplified spontaneous emission, beam pointing fluctuations, spatial hole burning, relaxation oscillations, red, green and blue lasers, cryogenic lasers, laser modeling, laser safety
  • Non-laser light sources: gas discharge lamps, arc and flash lamps, fluorescent lamps, mercury vapor lamps, metal halide lamps, high intensity discharge lamps, xenon lamps, sodium vapor lamps, superluminescent sources
  • Light pulses: bandwidth-limited pulses, parabolic pulses, mode-locked lasers, additive-pulse mode locking, regenerative amplifiers, chirped-pulse amplification, transform limit, pulse characterization, time–bandwidth product, frequency combs, timing jitter, parabolic pulses, Q-switched lasers
  • Laser material processing: laser cutting, drilling, welding, soldering and brazing, laser surface modification, hardening, laser additive manufacturing, laser micromachining, laser processing heads
  • Optical communications: optical fiber communications, fiber-optic links and networks, telecom windows, free-space optical communications, space division multiplexing, amplifier noise, bit error rate, bandwidth–distance product, optical modulators, photonic integrated circuits
  • Optical spectroscopy: laser absorption spectroscopy, time-resolved spectroscopy, Raman spectroscopy, multipass gas cells, spectrometers, spectrophotometers, tunable lasers, mid-infrared laser sources
  • Quantum optics and quantum effects: squeezed states of light, Glauber states, quantum wells, quantum dots, light forces, laser cooling, quantum noise, shot noise, Schawlow–Townes linewidth, quantum cryptography
  • Photovoltaics: photovoltaic cells, solar modules, solar power generation
  • Noise in optics: noise specifications, power spectral density, timing jitter, Gordon–Haus jitter, quantum noise, squeezed states of light, standard quantum limit, shot noise, relative intensity noise, phase noise, noise eaters, linewidth, stabilization of lasers

The Latest Encyclopedia Articles

This encyclopedia is not a static resource, but is constantly further extended to cover more topics and more details. Here you find the latest articles:

We also offer an RSS feed for new articles RSS-Feed for new articles.

Some Random Selection of Articles

Here are some randomly selected articles – just to make you curious:

Note that articles from our blogs – the Photonics Spotlight, the RP Software News and RP Photonics Marketing News - are not listed here; check them separately!