A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (elements), usually arranged along a common axis. Lenses are made from materials such as glass or plastic and are ground, polished, or molded to the required shape. A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly focus or disperse waves and radiation other than visible light are also called "lenses", such as microwave lenses, electron lenses, acoustic lenses, or explosive lenses.
A flight simulator is a device that artificially re-creates aircraft flight and the environment in which it flies, for pilot training, design, or other purposes. It includes replicating the equations that govern how aircraft fly, how they react to applications of flight controls, the effects of other aircraft systems, and how the aircraft reacts to external factors such as air density, turbulence, wind shear, cloud, precipitation, etc. Flight simulation is used for a variety of reasons, including flight training, the design and development of the aircraft itself, and research into aircraft characteristics and control handling qualities.
Stereoscopy is a technique for creating or enhancing the illusion of depth in an image by means of stereopsis for binocular vision. The word stereoscopy derives from Greek στερεός (stereos) 'firm, solid', and σκοπέω (skopeō) 'to look, to see'. Any stereoscopic image is called a stereogram. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope.
Schlieren photography is a process for photographing fluid flow. Invented by the German physicist August Toepler in 1864 to study supersonic motion, it is widely used in aeronautical engineering to photograph the flow of air around objects.
A collimated beam of light or other electromagnetic radiation has parallel rays, and therefore will spread minimally as it propagates. A laser beam is an archetypical example. A perfectly collimated light beam, with no divergence, would not disperse with distance. However, diffraction prevents the creation of any such beam.
A head-up display, or heads-up display, also known as a HUD or head-up guidance system (HGS), is any transparent display that presents data without requiring users to look away from their usual viewpoints. The origin of the name stems from a pilot being able to view information with the head positioned "up" and looking forward, instead of angled down looking at lower instruments. A HUD also has the advantage that the pilot's eyes do not need to refocus to view the outside after looking at the optically nearer instruments.
A glass cockpit is an aircraft cockpit that features an array of electronic (digital) flight instrument displays, typically large LCD screens, rather than traditional analog dials and gauges. While a traditional cockpit relies on numerous mechanical gauges to display information, a glass cockpit uses several multi-function displays and a primary flight display driven by flight management systems, that can be adjusted to show flight information as needed. This simplifies aircraft operation and navigation and allows pilots to focus only on the most pertinent information. They are also popular with airline companies as they usually eliminate the need for a flight engineer, saving costs. In recent years the technology has also become widely available in small aircraft.
2.5D perspective refers to gameplay or movement in a video game or virtual reality environment that is restricted to a two-dimensional (2D) plane with little or no access to a third dimension in a space that otherwise appears to be three-dimensional and is often simulated and rendered in a 3D digital environment.
Star Tours was a motion simulator attraction at several Disney theme parks, based on the successful Star Wars film series created by George Lucas. Set in the Star Wars universe, the attraction sent guests on an excursion trip to Endor, whilst being caught in an altercation between the New Republic and an Imperial Remnant. The attraction featured Captain "Rex" RX-24 along with series regulars R2-D2 and C-3PO.
A head-mounted display (HMD) is a display device, worn on the head or as part of a helmet, that has a small display optic in front of one or each eye. HMDs have many uses including gaming, aviation, engineering, and medicine.
Flight Unlimited II is a 1997 flight simulator video game developed by Looking Glass Studios and published by Eidos Interactive. The player controls one of five planes in the airspace of the San Francisco Bay Area, which is shared with up to 600 artificially intelligent aircraft directed by real-time air traffic control. The game eschews the aerobatics focus of its predecessor, Flight Unlimited, in favor of general civilian aviation. As such, new physics code and an engine were developed, the former because the programmer of Flight Unlimited's computational fluid dynamics system, Seamus Blackley, had left the company.
A motion simulator or motion platform is a mechanism that creates the feelings of being in a real motion environment. In a simulator, the movement is synchronised with a visual display of the outside world (OTW) scene. Motion platforms can provide movement in all of the six degrees of freedom (DOF) that can be experienced by an object that is free to move, such as an aircraft or spacecraft:. These are the three rotational degrees of freedom and three translational or linear degrees of freedom.
Microsoft Flight Simulator began as a set of articles on computer graphics, written by Bruce Artwick throughout 1976, about flight simulation using 3-D graphics. When the editor of the magazine told Artwick that subscribers were interested in purchasing such a program, Artwick founded Sublogic Corporation to commercialize his ideas. At first the new company sold flight simulators through mail order, but that changed in January 1979 with the release of Flight Simulator (FS) for the Apple II. They soon followed this up with versions for other systems and from there it evolved into a long-running series of computer flight simulators.
A synthetic vision system (SVS) is a computer-mediated reality system for aerial vehicles, that uses 3D to provide pilots with clear and intuitive means of understanding their flying environment.
In Gaussian optics, the cardinal points consist of three pairs of points located on the optical axis of a rotationally symmetric, focal, optical system. These are the focal points, the principal points, and the nodal points; there are two of each. For ideal systems, the basic imaging properties such as image size, location, and orientation are completely determined by the locations of the cardinal points; in fact, only four points are necessary: the two focal points and either the principal points or the nodal points. The only ideal system that has been achieved in practice is a plane mirror, however the cardinal points are widely used to approximate the behavior of real optical systems. Cardinal points provide a way to analytically simplify an optical system with many components, allowing the imaging characteristics of the system to be approximately determined with simple calculations.
A curved mirror is a mirror with a curved reflecting surface. The surface may be either convex or concave. Most curved mirrors have surfaces that are shaped like part of a sphere, but other shapes are sometimes used in optical devices. The most common non-spherical type are parabolic reflectors, found in optical devices such as reflecting telescopes that need to image distant objects, since spherical mirror systems, like spherical lenses, suffer from spherical aberration. Distorting mirrors are used for entertainment. They have convex and concave regions that produce deliberately distorted images. They also provide highly magnified or highly diminished (smaller) images when the object is placed at certain distances.
Full flight simulator (FFS) is a term used by national (civil) aviation authorities (NAA) for a high technical level of flight simulator. Such authorities include the Federal Aviation Administration (FAA) in the United States and the European Aviation Safety Agency (EASA).
A stand guidance system is a system which gives information to a pilot attempting to park an aircraft at an airport stand, usually via visual methods, leading to the term Visual Docking Guidance System (VDGS) and also A-VDGS This allows them to remain clear of obstructions and ensures that jetways can reach the aircraft.
A flight simulation video game refers to the simulation of various aspects of flight or the flight environment for purposes other than flight training or aircraft development. A significant community of simulation enthusiasts is supported by several commercial software packages, as well as commercial and homebuilt hardware. Open-source software that is used by the aerospace industry like FlightGear, whose flight dynamics engine (JSBSim) is used in a 2015 NASA benchmark to judge new simulation code to space industry standards, is also available for private use. A popular type of flight simulators video games are combat flight simulators, which simulate combat air operations from the pilot and crew's point of view. Combat flight simulation titles are more numerous than civilian flight simulators due to variety of subject matter available and market demand.
