Laser Fundamentals

In a few decades since the 1960s, the laser has gone from being a science fiction fantasy, to a laboratory research curiosity, to an expensive but valuable tool in esoteric scientific applications, to its current role as an integral part of everyday tasks as mundane as reading grocery prices or measuring a room for wallpaper. Any substantial list of the major technological achievements of the Twentieth Century would include the laser near the top. The pervasiveness of the laser in all areas of current life can be best appreciated by the range of applications that utilize laser technology. At the spectacular end of this range are military applications, which include using lasers as weapons to possibly defend against missile attack, and at the other end are daily activities such as playing music on compact disks and printing or copying paper documents. Somewhere in between are numerous scientific and industrial applications, including microscopy, astronomy, spectroscopy, surgery, integrated circuit fabrication, surveying, and communications.

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Laser Fundamentals – Review Articles

Introduction to Lasers

The special nature of laser light has made laser technology a vital tool in nearly every aspect of everyday life including communications, entertainment, manufacturing, and medicine.

Laser Systems for Optical Microscopy

The lasers employed in optical microscopy are high-intensity monochromatic light sources, which are useful for a variety of techniques including optical trapping, lifetime imaging studies, and TIRFM.

Laser Fundamentals – Interactive Tutorials

Laser Energy Levels

Population inversion can be produced in two ways: by creating excess atoms in a high energy state, or reducing the population of a lower energy state. See the metastable states for both three-level and four-level laser systems.

Spontaneous and Stimulated Processes

One important concept necessary in understanding laser operation is that quantization of energy in the atom results in discrete energy levels. Explore concepts of spontaneous absorption, emission, as well as stimulated emission.

Stimulated Emission in a Laser Cavity

Explore how laser amplification occurs starting from spontaneous emission of the first photon to saturation of the laser cavity and the establishment of a formal equilibrium state in this interactive tutorial.

Argon-Ion Lasers

Learn more in this tutorial about the well-explored family of ion lasers and how the argon-ion laser operates in the visible and ultraviolet spectral regions by utilizing an ionized species of the noble gas argon.

Diode Lasers

Learn more in this interactive tutorial about semiconductor diode lasers having sufficient power output to be useful in optical microscopy are now available from a host of manufacturers

Ti:Sapphire Mode-Locked Lasers

Discover more about the self mode-locked Ti:sapphire pulsed laser and how it is currently one of the preferred laser excitation sources in a majority of multiphoton fluorescence microscopy investigations.

Nd:YLF Mode-Locked Pulsed Lasers

Many applications, such as illumination techniques in fluorescence optical microscopy, require a reliable power laser source enabling efficient frequency conversions as explained in this interactive java tutorial.

Compact Disk Lasers

Explore in this interactive tutorial the interactions between a laser beam and the surface of a spinning compact disk showing variations of how light is scattered or reflected back into a detector.

Laser Cavity Resonance Modes and Gain Bandwidth

Discover how varying the appropriate frequencies can alter curves describing the number of cavity modes and gain bandwidth of a laser in this interactive tutorial.

Contributing Authors

Kenneth R. Spring

Scientific Consultant, Lusby, Maryland, 20657.

Matthew Parry-Hill, Christopher A. Burdett, Robert T. Sutton, Thomas J. Fellers and Michael W. Davidson - National High Magnetic Field Laboratory, 1800 East Paul Dirac Dr., The Florida State University, Tallahassee, Florida, 32310.