Photonics Handbook

Early fiber lasers were inefficient and limited to low powers, until more effective methods emerged to deliver the pump light into the cladding. Valentin Gapontsev, founder and CEO of IPG Photonics,...

Except for direct illumination from the sun, laser, or other light source, everything we see or detect is ultimately scattered light. Light can be scattered or rescattered during its propagation to...

Electrical engineers are very familiar with the effects of shot noise, thermal noise, flicker noise and crosstalk, and recognize how these effects can reduce the signal-to-noise ratio (SNR) in their...

Optical fibers are made from either glass or plastic. Most are roughly the diameter of a human hair, and they may be many miles long. Light is transmitted along the center of the fiber from one end...

The use of precision polymer optics is becoming an increasing necessity today as products demand sophisticated light handling components to achieve desired results. Polymer optics can be thought of...

In their earliest forms, UV bandpass filters that were optimized for wavelengths less than 400 nm, such as the Schott UG or the Hoya U-series, were constructed of absorbing compounds in glass. Such...

What are thin-film coatings? The purpose of any optical thin-film coating is to modify the transmittance and reflectance properties of the substrate material to which they are applied. Most coatings...

Double-sided processing is a batch-type process that uses planetary action — generally with loose, abrasive particles suspended in a liquid vehicle — to abrade material almost equally...

An integrating sphere’s function is to spatially integrate radiant flux (light). However, before one can optimize a sphere design for a particular application, it is important to understand how...

Over 60 years have passed since the first demonstration of a laser in 1960. After the initial spark of interest, lasers were for a while categorized as “a solution waiting for a problem,”...

The first high-reflectance mirror coatings for the UV and vacuum UV (VUV) were of the Al + MgF2 type produced in the late 1950s. Coatings of this design are still used today for multigas cavity...

An optical time-domain reflectometer sends short pulses of light into a fiber and measures its reflections as a function of time. The delay of these reflections to the detector as well as their...

With a specific gravity of 1.85 g/cm3, beryllium is the lightest metal that is workable. It is 45 percent lighter than aluminum and approximately five times as stiff. Its stiffness to weight ratio...

The ubiquitous Nd:YAG laser has played many roles over the years. For the military, it has provided rangefinding and target designation capabilities. When used with nonlinear optics or as a pump...

That portion of the spectrum that the eye can see — and its rainbow of colors — is rather small, covering approximately 360 to 830 nm. What colors we perceive depends on wavelength, while...

The common polycrystalline materials used for optical thin-film materials do not satisfy the requirements of telecommunications because of the instabilities caused by moisture absorption in their...

Infrared system design is not, like some circuit design, a synthetic process. One cannot start by stating the problem and proceeding in an orderly fashion to a final solution. Rather, we guess a...

Hyperspectral imaging spectroscopy has developed dramatically from a large, complex, remote-sensing satellite- or aircraft-based system into a rugged, compact, economically priced imaging and...

Intensity and uniformity can be described using different physical attributes, which makes interpreting requirements somewhat confusing. This article intends to provide an explanation and serve as a...

The basic difference between the household mirror and the optical mirror is that one is coated on the back surface and the other is coated on the front. For optical applications, a front-surface...

All optical spectrometry techniques rely on the measurement of radiant power. The configuration of the instrument varies based on the measurement technique: absorption, emission, luminescence, or...

Ultraprecision machining can be defined in general terms as the removal of material from a substrate utilizing a machine tool that operates at a resolution of 10 nm (0.4 μin.) or less. The...

When physical structures get very small — on the order of molecular or atomic sizes with one or more dimensions on the nanoscale — their behavior and interactions with energy, including...

Lenses come in a variety of shapes, sizes and materials. They can be made of a single piece of glass or have multiple elements; their surfaces can be spherical, aspheric or cylindrical; they can be...

NSOM is suitable for studies on the mesoscopic scale (several tens to hundreds of molecular dimensions). It has become an important tool in research and applications of semiconductors, organic layers...