Photonics Handbook

Diffraction gratings are optical components with a periodic structure that separate light into beams traveling in predictable directions based on their wavelength. The grating acts as the dispersive...

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...

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...

Silicon photonics is widely considered a key enabling technology for further development of optical interconnect solutions needed to address growing traffic on the internet. From the first submarine...

Since its first successful operation in 1960 at Hughes Research Labs, the laser technology has been at the center of innovation and research. Semiconductor lasers first made their appearance in 1962...

By its original definition, a nanopositioning device is a mechanism capable of repeatedly delivering motion in increments as small as one nanometer. Lately demands from industry and research have...

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...

Optical design software allows the user to develop a configuration of optical elements that manipulate the trajectory of light for the purposes of creating an image, illuminating a target, coupling...

Surface quality has become one of the most poorly understood specifications in the optics industry. A significant portion of the confusion stems from the two major competing (and largely...

Single-crystal sapphire has been the material of choice for defense and other applications that require extremely durable optics, but aluminum oxynitride (ALON) and magnesium aluminate (spinel) have...

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...

Neodymium-doped crystals and glasses such as Nd:YAG (neodymium:yttrium aluminum garnet) have long been used as laser gain materials. Optically pumped, they produce an output wavelength close to 1...

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...

The optical materials selected for an optical system depend upon the application, the required system performance and the environment in which the system is to perform; thus the materials’...

In general, there are three common approaches to reducing mechanical excitation of photonic systems. The first is identifying the sources of vibration and implementing ways to eliminate or reduce...

The wavelength range of commercially available LEDs with single-element output power of at least 5 mW is 275 to 950 nm. Each wavelength range is made from a specific semiconductor material family,...

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...

Image intensification, the basis of night vision, is a complex conversion of energy particles that occurs within a vacuum tube. An image-intensifier system works by collecting photons through an...

Excimers are pulsed gas lasers that deliver high output power and pulse energies in the ultraviolet and deep-ultraviolet wavelengths. This enables them to power applications that cannot be supported...

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...

Photonics Rules of Thumb Scientists and engineers tend to want to answer simple relational questions with a blackboard covered with equations, even when questioners just want a rough estimate to...

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...

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...

Optical coatings are deposited as thin-film multilayers of a variety of materials using specific deposition techniques. Coatings are applied to optical components that are intended for use at...

Reflected-ultraviolet imaging is a rather mysterious area of the imaging field. There is relatively little actual UV imagery to be found on the Internet or in the literature compared to near-infrared...

Like other CTDs, the CID imager uses hundreds of thousands (up to 4 million) pixel elements to capture optical images, and converts the light into an electronic charge which may be displayed on a...

To the novice or casual user of optics, the acquisition of an optical system can be a very difficult experience. Failure to understand the ground rules can result in unnecessarily high cost, late...

While some design engineers know exactly what they need from their laser diode, others may choose a partner to navigate what can be a complex development process. Laser diode manufacturers know which...

Radiometry involves several activities. The two most common are the description and measurement of optical radiation, and, starting with the knowledge of some aspects of optical radiation at one...

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....

Controlling and minimizing heat output is desirable in most lighting applications. For example, conventional incandescent light sources are very inefficient with only a small portion of the...

The market for flat panel displays (FPDs) has undergone tremendous growth, driven mostly by increased demand for televisions, cell phones, computers, digital cameras and MP3 players. Similarly,...

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...

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...

High-brightness LEDs have found their way into applications such as signs and displays, cell phone flash modules, automotive lighting and general illumination. Some applications, however, such as...

Conditions on the factory floor and in industrial cleanrooms with high-capacity air filtration systems can hamper the use of interferometry. Another problem is the testing of large-aperture mirrors...

Optics today needs alchemy, and the forces that motivate microchip technology are a key reason why. Today, light can transmit and process digital information as well as electricity can — in...

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...

Simple Meniscus Lens The simple meniscus lens is almost universally used in inexpensive cameras. To get an image of good quality it must be used with a separate aperture stop, reducing the...

For any discussion of laser beam diagnostics, it is first necessary to define some terms that characterize beam properties. Broad definitions can include measurements of laser energy or power,...

Many linear materials proceseqsing applications call for lasers with continuous-wave (CW) output. For example, early stereolithography systems were based on CW lasers such as argon-ion or HeCd. To...

Particle image velocimetry (PIV) is an experimental tool in fluid mechanics and aerodynamics. The basic principle involves photographic recording of the motion of microscopic particles that follow...

Laser diodes vary widely in their wavelengths, powers, spectra and beam quality. Yet they share two fundamental components with all other lasers: an optical amplifier and a resonator that confines...

Imaging has long been used in industrial processes to measure, monitor, control, or otherwise manage the production of goods. The challenge to the process designer is to develop a tool that captures...

As bit rates increase to meet expanding demand, systems have become increasingly sensitive to polarization-related impairments. These include polarization mode dispersion (PMD) in optical fibers,...

To Isaac Newton the problem was clear, and in 1704 he realized the effects of atmospheric turbulence on image formation. Just as heat waves shimmering above a hot patch of ground can distort our...

As system and cable installers try to optimize their links, the preferred method has become high-speed DWDM. This demand for bandwidth has led to the development of new test and measurement...