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...

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...

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...

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...

As recently as five years ago, shopping for a microscope light source was fairly straightforward. For routine applications, it was tungsten halogen, typically 100 W, while for fluorescence, it was an...

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...

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...

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...

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...

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’...

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,...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

Camera resolution depends upon the optical blur diameter and the detector size. Schade combined these to create an equivalent resolution that is a function of Fλ/d where F is the focal ratio,...

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...

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...

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),...

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...

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...

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,...

The applications where rapid detection of light is a must are many. They include a wide variety: semiconductor inspection, gene sequencing, oil well logging and high-energy physics. The reasons for...

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...

In the beginning, automated inspection focused on the camera and optics, the algorithms, the interface hardware and the processor. Only rarely was attention paid to the lighting system or lighting...

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 scope of optical spectroscopic instrumentation is indeed very broad. Many analytical methods rely on the interaction of radiation with matter and are often described in the context of quantum and...