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...

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,...

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...

Superresolution optical microscopy, for which the Nobel Prize was awarded to Eric Betzig, Stefan Hell, and William Moerner in 2014, has been one of the most momentous developments in the life...

The benefits of aspheric lenses are numerous: They allow for a reduction in spherical aberrations and are ideal for focusing or collimating light, as they can achieve a low ƒ-number. Aspheres...

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...

Prefixes for Binary Multiples The International Electrotechnical Commission (IEC) in 1998 approved as an IEC International Standard names and symbols for prefixes for binary multiples for use...

Technological advances have resulted in new, higher-quality sensors that enable machine vision cameras to deliver greater features and functionality at a lower cost than ever before. These factors...

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...

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...

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...

When purchasing an industrial laser system, the astute buyer will look for a Class 1 laser product — a system where the laser beam hazard is completely enclosed and there is no potential laser...

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...

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...

As you operate your laser, only a portion of the electrical power sourced from your laser driver converts to light energy. The remainder turns to heat, and the buildup of that thermal energy presents...

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...

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...

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,...

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...

International System of Units (SI) SI Prefixes Multiples Factor Name Symbol 1024 yotta Y 1021 zetta Z 1018 exa E 1015 peta P 1012 tera T 109 ...

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) =...

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...

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...

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...

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...

There is a growing market for imaging systems that provides an immediate, slow-motion view of a process that allows one to see events that happen too quickly for the human eye to perceive or...

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),...

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...

Manufacturing the laser diode is complicated by the existence of multiple proprietary techniques and intellectual property barriers together with complex device physics and unique materials. ...

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...

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...

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...

Illumination design has developed rapidly to include not only automotive headlamps and street lamps, but also backlit displays, fluorescent panel lighting, light-emitting diode or laser sources, 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...

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...

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...

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...

Photonic components are key elements for the information technology (IT). Photonics technology covers the generation of information (cameras, sensors), its transportation (optical communication),...

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...

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...