Photonics Handbook

Aspheric surfaces are powerful tools that combine the optical corrections of multiple lenses into a single element (Figure 1) and affect performance in ways that spherical optics cannot. For example,...

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...

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,”...

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...

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,...

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...

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...

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...

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...

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...

If we were to estimate the output of a CCD or thermal camera, we would typically draw an image over the detectors, aligning the image with the detector axes. We show it this way because it’s...

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...

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. ...

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...

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),...

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...

Applications facilitated by tunable lasers fall into two categories: situations in which one or more discrete wavelengths are not available from any single- or multiline fixed-wavelength laser, or...

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...

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...

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...

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...

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....

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...

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...

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...

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...

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...

A lens collects light from a point on an object and focuses it to a corresponding conjugate point on an image. Under most conditions, the lens fails at this task because of some error in the...

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...

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...

Abbe Error — Linear off-axis errors introduced by angular deviations coupled to a moment arm at the point of interest on stage mounted devices (θ in Figure 1). The effect of Abbe error...

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 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...

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...

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 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...

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...

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...

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...

By observing a few simple rules that govern diode lasers’ properties, driving them loses much of its mystery. Below its threshold current, a diode laser emits LED light with spontaneous...