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The Photonics Spotlight

The Photonics Spotlight – associated with the Encyclopedia of Laser Physics and Technology – is a “blog” (web log) with the purpose of highlighting interesting news and useful information in the area of photonics, particularly laser technology and applications. The content can be related to particularly interesting scientific papers or to other forms of publications, reporting for example cute new techniques, special achievements, or useful hints.

Note that the Spotlight articles (as well as those of the Encyclopedia) are citable. Permanent links are given for each article.

This blog is operated by of RP Photonics Consulting. Comments and suggestions are welcome. The news items are definitely not available for advertising, although we do offer certain advertising opportunities on our website.

You can read this content in various ways:

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And here are the articles:

2018-04-06Laser Physics: the Essential Roles of Phonons in Solid-state Lasers
2018-03-05Dependence on Raman Conversion on the Optical Bandwidth
2018-01-08Self-starting of Passively Mode-locked Lasers
2017-12-04Energy Levels of Solid-state Gain Media
2017-11-02Gaussian Apertures in Resonator Models: Not Only for Exotic Lasers, But Also for Gain Guiding
2017-10-03Importance of Spectral Wings on the Pulse Duration
2017-08-31Passive Mode Locking with Slow Saturable Absorbers: Surprisingly Stable!
2017-08-01Fiber Amplifiers: Modeling of Ultrashort Pulse Amplification with Saturation of Wavelength-dependent Gain
2017-04-12Does a Saturable Absorber in a Laser Lead to Passive Q switching or Mode Locking?
2017-03-15Interesting Features of Over-long Fiber Lasers
2017-02-17Photonics in Times of Trouble for International Trade
2017-01-27Second Opinion: a Useful Tool, also in Laser Technology!
2016-12-13Nonlinear Input–Output Curves for Lasers
2016-10-27Challenges for Nonlinear Frequency Conversion in Extreme Wavelength Regions
2016-09-12An Apparent Paradox Concerning Light Beams in Fibers
2016-08-11Mode Coupling in Optical Fibers: Selective Excitation of a Higher-order Mode with a Fiber Bragg Grating
2016-07-05The Round-trip Phase Shift in an Optical Resonator
2016-06-08Citations in the Encyclopedia of Laser Physics and Technology
2016-05-12Measurement of Absorption Spectra of Active Fibers: Not as Easy as One Might Think!
2016-04-04Photographs, Drawings and Videos for the Encyclopedia of Laser Physics and Technology
2016-02-26New Encyclopedia Articles
2016-01-27Finding Suppliers for Photonics Products
2015-11-28How to Store Light – and to Understand the Laser Principle
2015-10-17The Linewidth of Single-frequency Lasers
2015-09-24Q-switched Lasers: Nd:YVO4 Better Suited than Nd:YAG for High Pulse Repetition Rates
2015-08-08Gain Saturation with Pulses
2015-07-01Self-phase Modulation Causes Spectral Broadening – Does it Really?
2015-05-14Alignment Sensitivity of Laser Resonators – an Important Design Criterion
2015-04-10The Enormous Popularity of the RP Photonics Website
2015-03-11Strange Time Dependence of ASE from a Fiber Amplifier
2015-02-05Attenuating Laser Beams – not That Easy
2015-01-09New Tutorial: Modeling of Fiber Amplifiers and Lasers
2014-12-17How PhD Students Should Get Supported by Supervisors
2014-11-14Correctly Designing Frequency Conversion Stages: Not Easy, but Worthwhile!
2014-10-03Fiber Optics Tutorials
2014-07-28How to Define the Mode Radius of a Fiber?
2014-06-27Shortages of Rare Earth Materials – a Problem for Photonics?
2014-05-1610-Year Anniversary of RP Photonics
2014-04-02Lower Emission Cross-section Leads to Higher Pulse Energy?!?
2014-01-17Mediation in Disputes on Laser Technology
2013-12-13Avoiding Trouble with Laser Specifications
2013-11-12Beam Quality Limit for Multimode Fibers
2013-09-24Simulation of a Q-switched Nd:YAG Laser:
Numerical Beam Propagation Reveals What Happens, Analytical Reasoning Explains It
2013-08-26Frequency Doubling and the Reverse Process
2013-07-08Amplified Spontaneous Emission in Fiber Amplifiers
2013-06-13Two New Photonics Newsletters
2012-08-06The New RP Photonics Buyer's Guide
2012-03-12New Raman Lasers
2012-03-03Conflicting Definitions of s and p Polarization
2012-02-03Simulation Software: Use Commercial Products or Home-Made Software?
2011-12-23Kerr-lens Mode-locked Thin-disk Laser
2011-06-10Are Compact Resonators More Stable?
2011-05-28Explanation for the Mode Instability in High-power Fiber Amplifiers with Few-mode Fibers
2011-03-13What if Solid-State Laser Transitions Would Be Much Stronger?
2011-02-10Fiber Lasers: More Difficult to Design than Bulk Lasers
2011-01-05Femtosecond Fiber Amplifiers: Unlimited Peak Power?
2010-09-02Why LEDs are Energy-efficient, and Why They Could Well Increase Energy Consumption
2010-07-27Special SESAMs for Mode-locked High-power Lasers?
2010-07-12Laser Development: Get an Expert Early on!
2010-06-09Poor Man's Isolator
2010-05-14Plagiarism, Exploiting the Encyclopedia of Laser Physics and Technology
2010-04-26Resolution and Accuracy of Measurements
2010-04-16Why Large Mode Area Waveguides Do Not Work for Laser Diodes
2010-04-08Creating a Top-hat Laser Beam Focus
2010-03-22All-in-one Concepts versus Modular Concepts
2010-03-15Spatial Walk-off and Beam Quality in Nonlinear Frequency Conversion
2010-03-09Nonlinearities in Fiber Amplifier Modeling
2010-03-03Thresholds for Nonlinear Effects in Fiber Amplifiers
2010-02-26New Scientific Paper: Timing Jitter and Phase Noise of Mode-locked Fiber Lasers
2010-02-06Scientific Conferences and Publications: Emphasize Device Performance or Insight?
2010-01-29Far From Maturity: The Photonics Industry
2010-01-22Pumping Fiber Lasers with Fiber Lasers
2010-01-11Beams of Laser Pointers: Visible in Air?
2009-12-31Tilt Tuning of Etalons
2009-12-13Johnson–Nyquist Noise in Photodiode Circuits
2009-12-08Increased Output Power of a Laser with Forced Tuning
2009-11-22The Beam Focus – Not Just a Demagnified Version of Your Beam
2009-11-18Articles and a Quiz on Photonics Issues
2009-11-13Photodetection: Optical and Electrical Powers
2009-11-03Coherent Light from a Bulb?
2009-10-19Risk Factors for Science Fraud and the Scientist's Responsibility
2009-10-12Cold Light from the Hottest Bodies and from Cool Devices
2009-10-08Nobel Prize for Charles K. Kao for Pioneering Work on Optical Fibers
2009-10-03Peak Intensity of Gaussian Beam
2009-09-27Lasers with Short Upper-state Lifetime
2009-09-19Are Laser Resonators Power Scalable?
2009-09-07Anniversary: 5 Years of the Encyclopedia of Laser Physics and Technology
2009-09-01Fresnel Reflections from Double Interfaces
2009-08-22Jitter and Phase Noise of Mode-locked Fiber Lasers
2009-08-14Progress on Green Laser Diodes
2009-08-12What is an Optical Transistor?
2009-07-29No Beat Note for Orthogonal Modes
2009-07-23Submit Photographs for the Encyclopedia of Laser Physics and Technology
2009-07-21Signal-to-Noise Ratio and Measurement Bandwidth
2009-07-09Gain-guiding Index-antiguiding Fibers
2009-06-29Doing Things Properly: It's the Economy, Stupid!
2009-06-23Coherence – a Black-or-White Issue?
2009-06-08Prizes of the European Physical Society
2009-06-025 Years of RP Photonics Consulting
2009-05-22Interference Effects with Imbalanced Intensity Levels
2009-05-13The Minimum Time–Bandwidth Product
2009-04-28SPIE Field Guides
2009-04-19Last Chance to Get the Encyclopedia of Laser Physics and Technology Cheaper
2009-04-17Miniature Laser Projectors – The Next Big Laser Thing?
2009-04-06Laser Pointers in Soccer Games: Not Necessarily Harmless
2009-04-05Stability of Resonators – an Ambiguous Term
2009-03-19Scientific Progress: not as Straight a Process as it Seems
2009-03-07Complicated Pulse Shapes from Q-switched Fiber Lasers
2009-03-02User Interfaces for Simulation Software
2009-02-13Laser Beam Deflections: The Angle–Diameter Product
2009-01-12Chaotic Lasing Generates Random Numbers
2009-01-05Extremely Long Mode-locked Fiber Laser
2008-12-16Why Fiber Amplifiers, not Fiber Lasers?
2008-11-25The Gouy Phase Shift Speeds up Light
2008-11-08Validating Numerical Simulation Software
2008-10-20Rate Equations – An Example for Stiff Sets of Differential Equations
2008-10-03Wavelength-Tunable Lasers: Does the Tuner Degrade the Power Efficiency?
2008-09-24Decoupling Pulse Duration and Pulse Energy
2008-09-10Unpolarized Single-Frequency Output
2008-08-28Photographs for the Encyclopedia of Laser Physics and Technology
2008-08-15Print Version of the Encyclopedia of Laser Physics and Technology
2008-07-26Beat Signals with Zero Linewidth
2008-07-13The Simplified History of the Michelson–Morley Experiment
2008-07-02Stronger Focusing Avoids SESAM Damage
2008-06-20All-in-One Ultrafast Laser Systems
2008-06-13Heisenberg's Uncertainty Principle and the Transform Limit
2008-06-06Fiber Lasers Which Are No Fiber Lasers
2008-05-25Einstein and the Laser
2008-05-13Easier Self-Starting Passive Mode Locking for Short Lasers
2008-05-05Length of a Photon
2008-04-28Different Kinds of Polarization
2008-04-22Abused Photonics Terms: Coherence
2008-04-15Abused Photonics Terms: Modes
2008-04-02Solitons: Lower Dispersion, Stronger Dispersive Effects!
2008-03-26Mode-Locked Lasers: Lower Average Powers in Shorter Pulses
2008-03-17Ultrafast Fiber Lasers: Re-Inventing Mode Locking
2008-03-10Automatic Phase Matching
2008-03-04What is a “High” Laser Beam Quality?
2008-02-22Launching Light from a Bulb into a Single-Mode Fiber
2008-02-14How Laser Development Can Go Wrong
2008-02-12Factor 2 in the Equation for Cross-Phase Modulation
2008-02-03Quantifying the Chirp of Ultrashort Pulses
2008-01-27Beam Quality in Second-Harmonic Generation
2008-01-14Frequency Doubling: Long Pulses Cause Trouble
2008-01-06Saturation Intensity or Saturation Fluence of a Saturable Absorber or a Laser Gain Medium: What Matters?
2007-12-18The Role of Laser Safety Goggles
2007-12-11The Idler Wave - Essential for Parametric Amplification and Oscillation
2007-12-03New Paper on Power Scaling of Lasers
2007-11-26Solving Laser Problems Step by Step
2007-11-19Walk-Off and Phase-Matching Bandwidth in Nonlinear Crystals
2007-11-10Retirement of Prof. David C. Hanna
2007-11-02Ultrafast Laser Kills Viruses
2007-10-31Thermal Equilibrium in Laser Crystals
2007-10-25The Gain Bandwidth of Laser Crystals and Glasses
2007-10-17Why the Second-Harmonic Beam is Smaller
2007-10-11Understanding Fourier Spectra
2007-10-07Effective Refractive Index: Correcting a Common Belief
2007-09-27Light Plus Light = Darkness: No Energy Problem, but Quantum Weirdness
2007-09-21Optimum Crystal Length for Frequency Doubling
2007-09-13Using Figures of the Encyclopedia in Your Publications, and Citing the Encyclopedia
2007-09-07Power Scaling in Downward Direction
2007-09-01Stimulated Brillouin Scattering: Lower Peak Power, Stronger Effect?
2007-08-27Distant Healing of Lasers
2007-08-23An OPO Without Resonator Mirrors
2007-08-22Saturation of Pump Absorption - An Important Issue?
2007-08-15Light = Electromagnetic Waves?
2007-08-06Fiber Amplifiers: More ASE for Larger Core with Higher NA?
2007-07-30Fiber Amplifiers: Stronger ASE in Backward Direction
2007-07-25Higher Heat Generation Density, Stronger Thermal Effects?
2007-07-16Mode Competition - Increased or Decreased by Spatial Hole Burning?
2007-07-11What is a Beam Width, Beam Size, and a Beam Waist?
2007-07-06Promoting Dangerous Practices in Laser Labs
2007-07-01Nonsensical Regulations Undermine Laser Safety
2007-06-24The Plague of a Narrow Emission Linewidth
2007-06-11Beam Quality Measurements Can Easily Go Wrong
2007-06-01Characterize Your Pump Beam!
2007-05-26Optical Isotropy: Nonlinear Interactions are Different!
2007-05-19Why Strong Birefringence in Fibers Helps
2007-05-10Fundamental Limitation for sigma-tau Product, Gain Efficiency, and Laser Threshold
2007-04-28Easier Launching into Fibers with Large Mode Area?
2007-04-16Questions and Answers on Shot Noise
2007-04-01The Ideal Pump Intensity Distribution in an End-Pumped Solid-State Laser
2007-03-23Explaining the Nature of Photons to Lay Persons
2007-03-16Time To Market and the Economics of Laser Development - or How to Cause Great Financial Damage without Spending Money
2007-03-11Divided-Pulse Amplification
2007-03-09The Trouble with Crystal and Coating Damage
2007-03-05More Efficient Frequency Doubling with Shorter Pulses?
2007-02-26No Laser, no Result?
2007-02-22Lossy Laser Cavities
2007-02-16The Science of Biophotons
2007-02-09Papers Reporting Yet Another Laser Crystal
2007-02-04Continuing Struggle for Larger Fiber Mode Areas
2007-01-27Noise Figure of Amplifiers
2007-01-21Operation Far Above Threshold
2007-01-15Origins of Heating in Laser Crystals
2007-01-09The Myth of Fiber-Optic Polar Bears
2007-01-05Why the Encyclopedia of Laser Physics and Technology is Successful
2006-12-31Peak Position of an Optical Spectrum
2006-12-16Dangerous Green Laser Pointers
2006-12-09The Laser Industry - High Tech or Low Tech?
2006-12-03Diffraction in Optical Fibers
2006-11-28The Role of Diffraction in Optical Resonators
2006-11-21The Resonator Mystery
2006-11-16Laser Models - not Always Useful
2006-11-04Nd:YVO4 Laser with Polarization-Independent Pump Absorption
2006-11-02Reflection Spectrum of Tilted Dielectric Mirror
2006-10-26Residual Transmission Through Highly Reflecting Mirrors
2006-10-22Lasers Attract Dust to Cavity Mirrors
2006-10-17A Cute New Imaging Technique Named Compressive Imaging
2006-10-16Using a Current Amplifier for Optical Power Measurements and Recording with a Photodiode
2006-10-15Fivehundred Articles in the Encyclopedia of Laser Physics and Technology
2006-10-09Correct Specifications for Laser Noise - Valuable but Hard to Obtain
2006-10-04Higher-Order Modes of Fibers: a Solution for Single-Mode Guidance with Large Mode Area?
2006-10-01Stability Zones of Laser Resonators
2006-09-29Frequency Dependence of the Conversion Efficiency for Frequency Doubling
2006-09-22Coherence Length of Ultrashort Pulses
2006-09-21Power Scaling Limits of Optical Parametric Amplifiers
2006-09-16Q-switched Lasers: YAG versus Vanadate
2006-09-06Quenching Degrades the Efficiency of Some Ytterbium-Doped Gain Media
2006-09-03Single-Frequency Operation Stabilized by Spatial Hole Burning
2006-09-03Resolution of Conundrum: Threshold Power for Parametric Nonlinear Interactions
2006-09-01Test Yourself with the Photonics Quiz
2006-08-23Lasers with Nonlinear Input–Output Characteristics
2006-08-20Lower Noise from Longer Lasers
2006-08-18Resolution of Conundrum: No Magnetic Field on the Axis of a Coil
2006-08-15The Effect of a Double Pass in a Frequency Doubler
2006-08-12Understanding Quasi-Three-Level Lasers
2006-08-10Single-Mode Fibers with Large Mode Areas
2006-08-01Lasers Disturbed by Vacuum?
2006-07-30Threshold Power for Parametric Nonlinear Interactions
2006-07-24Beam Distortions in Laser Cavities
2006-07-23Single-Atom Lasers
2006-07-22No Magnetic Field on the Axis of a Coil?
2006-07-21Photonics and Laser Technology Blogs – Where Are They?
2006-07-16Spontaneous Emission and Amplifier Noise
2006-07-14Lasers Like it Cool
2006-07-10Strength of Thermal Lensing Effects
2006-07-05Laser Design: Side Product or the Basis of Laser Development?
2006-07-01Lifting the Confusion Concerning Doping Concentrations
2006-07-01Characterizing a Cavity with a Frequency Comb
2006-07-01With Wavelength Combs to Picometer Resolution


… and keep in mind that the competent technical consulting services of RP Photonics could be very useful for your business!