Photonics Handbook

Photonics is the study of light and other types of radiant energy whose quantum unit is the photon. The impact of photonics on research, technology, navigation, culture, astronomy, forensics, and...

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...

There are three fundamental properties of light: intensity, wavelength, and polarization. Almost all cameras today are designed for monochrome or color imaging. A monochrome camera is used to measure...

With the understanding of aspheric lens manufacturing provided in part one of this article, designers have the tools to optimize their aspheres; the next step is to understand how to specify and...

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...

Flat optics generally perform three main functions: They transmit light (windows), reflect light (mirrors), and fold light (prisms). While most optical manufacturers make spherical and flat optics, a...

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...

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...

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...

An interferometer is an instrument that compares the position or surface structure of two objects. The basic two-beam division of amplitude interferometer components consists of a light source, a...

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...

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...

Since their invention in the late 1960s, charge-coupled devices, also called CCDs, have found widespread use in imaging applications. Electronic cameras based on CCD technology are used in...

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...

Spectral selection is a powerful tool that enhances conventional imaging tremendously. Most imaging systems, including the human eye, are designed to image light over a broad range of the spectrum....

An optical coating engineer is frequently confronted with a difficult specification for a coating. Often the difficulty in the specification results from the particular form of the optical system. If...

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...

Images are produced by many means: cameras, x-ray machines, electron microscopes, radar and ultrasound. They are used in the entertainment, medical, scientific and business industries; for security...

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...

Plate beamsplitters Plate beamsplitters consist of a thin plate of optical crown glass with a different type of coating deposited on each side. The first surface is coated with an all-dielectric...

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...

An indicator of how well the entire system performs is a measurement called bit-error-ratio (BER). Acceptable BERs range from one error per billion to one per trillion bits transmitted. It is rare...

The use and importance of colorimetry has grown in unison with the increase of global manufacturing and processing. When plastic automotive trim produced on one continent must match a painted metal...

There are three fundamentally different dispersive phenomena in optical fiber, of which polarization mode dispersion (PMD) is the most complex. In digital multimode fiber systems, a light pulse...