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...

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...

Developed in the early 1990s, the silicon photomultiplier (SiPM) is a solid-state photodetector whose sensitivity to light rivals that of a photomultiplier tube (PMT) in a regime where a few hundred...

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...

Materials processing with lasers is actually a broad term for a diverse range of applications. The major categories of these uses, and the lasers that service them, are summarized Table 1. At one...

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...

The term fluorescence is often applied as a synonym for photoluminescence, although luminescence actually covers fluorescence and phosphorescence. Both of these terms describe the process of...

Many common spectroscopic measurements require the coordinated operation of a detection instrument and light source, as well as data acquisition and processing. Integration of individual components...

When evaluating the surface of a component, surface roughness can be assessed by eye or by rubbing it with a fingertip. Common expressions include “shiny,” “lusterless and...

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...

Profiling beams under 10 µm in size is one of the more challenging beam profiling applications. There are numerous reasons for this, including the very small size. Focal plane arrays commonly...

Given the pace at which technology advances, there always seems to be a learning curve. With the abundance of consumer electronics available, there typically is no right or wrong way to use these...

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...

Light is a versatile tool for investigating physical and chemical processes in nature. Any specific system being analyzed may, through the light it emits or reflects, communicate information about...

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...

Laser development for the microscopy market continues to be driven by key trends in applications, which currently include superresolution techniques, multiphoton applications in optogenetics and...

For rotationally symmetric optical systems, either the lens or the detector moves along the optical axis to maintain optical performance. If the compensating axial motion is accomplished without the...

Physical Constants & Conversion Factors Length [I] 1 meter (m) = 39.3700 in. = 3.280833 ft = 1.093611 yd 1 kilometer (km) = 0.6213711 mi = 0.53996 nautical mi 1 micron (µm) =...

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...

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...

Any number of medical, industrial, and analytical applications requires the detection of light. Chemiluminescence, bioluminescence, fluorescence, and atomic absorption are just a few, and all require...

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...

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,”...

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...

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...

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...

The basic setup in laser perforation includes a pulsed laser, a lens and either a moving mirror, a rotating web or both. Each laser pulse creates a hole in the material. During the blank time in...

Charged-injection device imagers are metal-oxide semiconductor (MOS) detectors that can be fabricated using PMOS, NMOS and CMOS integrated circuit technology, and may be configured as a...

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...

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...

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...

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...

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...

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...

Measuring pulsed-beam lasers has generally required the use of a CCD array profiler. This is a reasonable solution for low-power lasers in the UV and visible wavelength range, but these require...

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...

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...

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...

The digital camera represents an integration of optics, mechanics and electronics consisting of three layers (Figures 1a, b and c). The top and the middle layers are printed circuit boards (PCBs),...

Attentuation Region (or Blocking) The spectral region over which very low transmission is required. Attenuation requirements are generally specified in percent transmission over a given spectral...

Just as an electronic connector provides a pluggable connection between electronic circuits, a fiber optic connector provides an optical one. The goal is joining a fiber to a transmitter, receiver or...

Designing devices that incorporate ultrathin films is an important means of enhancing yields. However, characterizing ultrathin films provides a challenge for mainstream metrology tools such as...

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...

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...