These tubes may differ both in the choice of the electron optical system and in the design of the coupling members.

The electron optical system may be either a magnetic or electrostatic one.

The electron optical system ( see fig. 14-1 ) is based in principle on the focusing action of concentric spherical cathode and anode surfaces.

It must be remembered that the fiber plates replace a glass window and a ( mica ) membrane, in addition to an optical output lens system.

The resolution limitations for a single stage are given by the inherent resolution of the electron optical system as well as the resolution capabilities of the cathodoluminescent viewing screen.

* Optical aberration, an imperfection in image formation by an optical system

An optical aberration is a departure of the performance of an optical system from the predictions of paraxial optics.

Aberrations occur because the simple paraxial theory is not a completely accurate model of the effect of an optical system on light, rather than due to flaws in the optical elements.

Aberration leads to blurring of the image produced by an image-forming optical system.

The Gaussian theory, however, is only true so long as the angles made by all rays with the optical axis ( the symmetrical axis of the system ) are infinitely small, i. e. with infinitesimal objects, images and lenses ; in practice these conditions are not realized, and the images projected by uncorrected systems are, in general, ill defined and often completely blurred, if the aperture or field of view exceeds certain limits.

These authors proved, however, that no optical system can justify these suppositions, since they are contradictory to the fundamental laws of reflexion and refraction.

Let S ( fig. 5 ) be any optical system, rays proceeding from an axis point O under an angle u1 will unite in the axis point O ' 1 ; and those under an angle u2 in the axis point O ' 2.

Development of the optical system is highly dependent on the presence of melanin, and the reduction or absence of this pigment in albinistic individuals may lead to

* the data rate ( e. g., in Gbit / s ) achieved in an optical communication system ; see bandwidth ( computing ).

When the PC starts up, the first job for the BIOS is the power-on self-test, which initializes and identifies system devices such as the CPU, RAM, video display card, keyboard and mouse, hard disk drive, optical disc drive and other hardware.

Among his results, Gauss showed that under a paraxial approximation an optical system can be characterized by its cardinal points and he derived the Gaussian lens formula.

A much more valuable and practical result of Brewster's optical researches was the improvement of the British lighthouse system.

Alternatively, the image can be photographically recorded by exposing a photographic film or plate directly to the electron beam, or a high-resolution phosphor may be coupled by means of a lens optical system or a fibre optic light-guide to the sensor of a CCD ( charge-coupled device ) camera.

ISO 9660, also referred to as CDFS ( Compact Disc File System ) by some hardware and software providers, is a file system standard published by the International Organization for Standardization ( ISO ) for optical disc media.

In 1955, Prokhorov and Basov suggested optical pumping of a multi-level system as a method for obtaining the population inversion, later a main method of laser pumping.

* In telecommunications, lambda indicates the wavelength in a wavelength-division multiplexing optical communications system.

This means that for an ideal optical system, the luminance at the output is the same as the input luminance.

However, blurring is not caused by random processes, such as light scattering, but can be well defined by the optical properties of the image formation in the microscope imaging system.

Settled phosphors, as generally used in image intensifiers, have low optical contact with the substrate surface, hence Af shall be assumed.

The elementary theory of optical systems leads to the theorem: Rays of light proceeding from any object point unite in an image point ; and therefore an object space is reproduced in an image space.

Math., 1858 ) and Ernst Abbe showed that the properties of these reproductions, i. e. the relative position and magnitude of the images, are not special properties of optical systems, but necessary consequences of the supposition ( in Abbe ) of the reproduction of all points of a space in image points ( Maxwell assumes a less general hypothesis ), and are independent of the manner in which the reproduction is effected.

Therefore, four loose families of more-efficient light transport modelling techniques have emerged: rasterization, including scanline rendering, geometrically projects objects in the scene to an image plane, without advanced optical effects ; ray casting considers the scene as observed from a specific point-of-view, calculating the observed image based only on geometry and very basic optical laws of reflection intensity, and perhaps using Monte Carlo techniques to reduce artifacts ; and ray tracing is similar to ray casting, but employs more advanced optical simulation, and usually uses Monte Carlo techniques to obtain more realistic results at a speed that is often orders of magnitude slower.

These lenses are analogous to but different from the glass lenses of an optical microscope that form a magnified image by focusing light on or through the specimen.

Just inside the perforations, on the left side of the image, is the analog optical soundtrack, with two channels encoded using Dolby Analog SR | Dolby SR noise reduction that can be dematrixed into four channels using Dolby Pro Logic.

The optical timecode used to synchronize a Digital Theater System | DTS soundtrack, which sits between the optical soundtrack and the image, is not pictured.

Some of these instruments produce a virtual image when applied to the human eye ; others produce a real image which can be captured on photographic film or an optical sensor, or can be viewed on a screen.

Dispersion staining is an optical technique that results in a colored image of a colorless object.

Serial time encoded amplified microscopy ( STEAM ) is an imaging method that provides ultrafast shutter speed and frame rate, by using optical image amplification to circumvent the fundamental trade-off between sensitivity and speed, and a single-pixel photodetector to eliminate the need for a detector array and readout time limitations The method is at least 1000 times faster than the state-of-the-art CCD and CMOS cameras.

The first is to utilize the shorter wavelength of ultraviolet electromagnetic energy to improve the image resolution beyond that of the diffraction limit of standard optical microscopes.

In transmission mode, the phase shift image provides a label-free quantitative measurement of the optical thickness of the specimen.

There are many types of microscopes, the most common and first to be invented is the optical microscope which uses light to image the sample.

Video camera tubes in the early days of television used the photoelectric effect, for example, Philo Farnsworth's " Image dissector " used a screen charged by the photoelectric effect to transform an optical image into a scanned electronic signal.

Other hardware components were supplied as follows: the beam-combining mirror from REOSC at Saint Pierre du Perray ; the spherical, folding and relay mirrors from Carl Zeiss AG in Oberkochen ; the external straylight baffles from CASA in Madrid ; the modulating grid from CSEM in Neuchatel ; the mechanism control system and the thermal control electronics from Dornier Satellite Systems in Friedrichshafen ; optical filters, the experiment structures and the attitude and orbit control system from Matra Marconi Space in Velizy ; instrument switching mechanisms from Oerlikon-Contraves in Zurich ; the image dissector tube and photomultiplier detectors assembled by the Dutch Space Research Organisation, SRON in The Netherlands ; the refocusing assembly mechanism designed by TNO-TPD in Delft ; the electrical power subsystem from British Aerospace in Bristol ; the structure and reaction control system from Daimler-Benz Aerospace in Bremen ; the solar arrays and thermal control system from Fokker Space System in Leiden ; the data handling and telecommunications system from Saab Ericsson Space in Gothenburg ; and the apogee boost motor from SEP in France.

Telecommunications engineering focuses on the transmission of information across a channel such as a coax cable, optical fiber or free space.

Facing increasing competition from China and South Korea, manufacturing in Japan today now focuses primarily on high-tech and precision goods, such as optical equipment, hybrid cars, and robotics.

The optical system focuses the thermal radiation onto the detector.

This problem was circumvented by the use of hydrodynamic " lenses "— explosive materials of differing densities — which would focus the blast waves inside the imploding sphere, akin to the way in which an optical lens focuses light rays.

This research-oriented campus focuses on precision metrology and intelligent manufacturing ; opto-electronics and optical communication ; and software and information technology.

In an optical instrument, the objective is the optical element that gathers light from the object being observed and focuses the light rays to produce a real image.

The optical system of the eye focuses light on the retina much like light is focused on the film or sensor in a camera.

Chongqing University of Posts and Telecommunications ( Simplified Chinese: 重庆邮电大学 ; abbreviation: CQUPT ) is a public university located in China's fourth municipality: Chongqing, which focuses on the research and education in the field of information and communications and enjoys a nation-wide reputation in the study of posts, telecommunications and information technology, especially for its research and commercialization in 3G mobile technologies, optical sciences and related digital research.

* DVD-Audio, optical DVD standard that focuses on high-definition and surround audio, published by the DVD Forum

In geometric optics, stigmatism refers to the image-formation property of an optical system which focuses a single point source in object space into a single point in image space.

Currently Neonode Inc (), the parent company, focuses solely on the development, licensing and selling of the company's patented optical touch technology.

The company focuses on solutions for multi-play services, business services, voice services, wireless, cellular backhaul, optical networking, Carrier Ethernet networks, TDM to Ethernet evolution, migration to all IP, network security, carrier of carriers and wavelength services.