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A holographic screen is a two-dimensional display technology that uses coated glass media for the projection surface of a video projector. "Holographic" refers not to a stereoscopic effect, but to the coating that bundles light using formed microlenses. The lens design and attributes match the holographic area. The lenses may appear similar to the Fresnel lenses used in overhead projectors. The resulting effect is that of a free-space display, because the image carrier appears very transparent. Additionally, the beam manipulation by the lenses can be used to make the image appear to be floating in front of or behind the glass, rather than directly on it. However, this display is only two-dimensional and not true three-dimensional. It is unclear if such a technology will be able to provide acceptable three-dimensional images in the future.
The display design can use either front or rear projection, in which one or more video projectors are directed at the glass plate. Each projector's beam widens as it approaches the surface and then is bundled again by the lenses' arrangement on the glass. This forms a virtual point of origin, so that the image source appears to be an imaginary object somewhere close to the glass. In rear projection (the common use case), the light passes through the glass; in front projection it is reflected.
Interactive holographic screens add gesture support to holographic screens. These systems contain three basic components:
The computer sends the image to the projector. The projector generates light beams which form the image on the screen. When the user touches the screen, a tactile membrane film reacts to these movements, generating electrical impulses that are sent back to the computer. The computer interprets the received impulses and modifies the projected image according to the information.
The projector generates the beams of light that will form the image on the screen's film, which is adhered to the crystal support. These crystal lenses can be a maximum of 16 millimeters (0.63 in) across. The projector is usually located behind the screen and must be placed a certain angle above or below the user's line of sight to avoid the dazzling the user. Therefore, it must be trapezoidal projector, so it can compensate for the deforming of the images at this angle of displacement.
The films are thin sheets of plastic applied to the crystal that allow both visualization and interactivity. There are two types of films:
Most initial uses of this technology are advertising-related, such as shop windows. [2] An interactive holographic screen can be mounted on the shop windows so that passersby can interact with it. Non-interactive holographic screens in shop windows can be coupled with artificial vision software to adapt ads based on the viewer's characteristics (age, sex, etc.).
These types of screens are often used for the display of Vocaloids at concerts because they simulate the illusion of a holographically-projected virtual performer.
Holography is a technique that enables a wavefront to be recorded and later reconstructed. It is best known as a method of generating three-dimensional images, and has a wide range of other uses, including data storage, microscopy, and interferometry. In principle, it is possible to make a hologram for any type of wave.
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.
An overhead projector, like a film or slide projector, uses light to project an enlarged image on a screen, allowing the view of a small document or picture to be shared with a large audience.
Display may refer to:
An LCD projector is a type of video projector for displaying video, images or computer data on a screen or other flat surface. It is a modern equivalent of the slide projector or overhead projector. To display images, LCD projectors typically send light from a metal-halide lamp through a prism or series of dichroic filters that separates light to three polysilicon panels – one each for the red, green and blue components of the video signal. As polarized light passes through the panels, individual pixels can be opened to allow light to pass or closed to block the light. The combination of open and closed pixels can produce a wide range of colors and shades in the projected image.
A display device is an output device for presentation of information in visual or tactile form. When the input information that is supplied has an electrical signal the display is called an electronic display.
A video projector is an image projector that receives a video signal and projects the corresponding image onto a projection screen using a lens system. Video projectors use a very bright ultra-high-performance lamp, Xenon arc lamp, metal halide lamp, LED or solid state blue, RB, RGB or fiber-optic lasers to provide the illumination required to project the image. Most modern projectors can correct any curves, blurriness and other inconsistencies through manual settings.
Digital light processing (DLP) is a set of chipsets based on optical micro-electro-mechanical technology that uses a digital micromirror device. It was originally developed in 1987 by Larry Hornbeck of Texas Instruments. While the DLP imaging device was invented by Texas Instruments, the first DLP-based projector was introduced by Digital Projection Ltd in 1997. Digital Projection and Texas Instruments were both awarded Emmy Awards in 1998 for the DLP projector technology. DLP is used in a variety of display applications from traditional static displays to interactive displays and also non-traditional embedded applications including medical, security, and industrial uses.
A spatial light modulator (SLM) is a device that can control the intensity, phase, or polarization of light in a spatially varying manner. A simple example is an overhead projector transparency. Usually when the term SLM is used, it means that the transparency can be controlled by a computer.
A 3D display is a display device capable of conveying depth to the viewer. Many 3D displays are stereoscopic displays, which produce a basic 3D effect by means of stereopsis, but can cause eye strain and visual fatigue. Newer 3D displays such as holographic and light field displays produce a more realistic 3D effect by combining stereopsis and accurate focal length for the displayed content. Newer 3D displays in this manner cause less visual fatigue than classical stereoscopic displays.
A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye.
An interactive whiteboard (IWB), also known as interactive board, interactive display, interactive digital board or smart board, is a large interactive display board in the form factor of a whiteboard. It can either be a standalone touchscreen computer used independently to perform tasks and operations, or a connectable apparatus used as a touchpad to control computers from a projector. They are used in a variety of settings, including classrooms at all levels of education, in corporate board rooms and work groups, in training rooms for professional sports coaching, in broadcasting studios, and others.
A front projection effect is an in-camera visual effects process in film production for combining foreground performance with pre-filmed background footage. In contrast to rear projection, which projects footage onto a screen from behind the performers, front projection projects the pre-filmed material over the performers and onto a highly reflective background surface.
A lenticular lens is an array of lenses, designed so that when viewed from slightly different angles, different parts of the image underneath are shown. The most common example is the lenses used in lenticular printing, where the technology is used to give an illusion of depth, or to make images that appear to change or move as the image is viewed from different angles.
Fulldome refers to immersive dome-based video display environments. The dome, horizontal or tilted, is filled with real-time (interactive) or pre-rendered (linear) computer animations, live capture images, or composited environments.
Large-screen television technology developed rapidly in the late 1990s and 2000s. Prior to the development of thin-screen technologies, rear-projection television was standard for larger displays, and jumbotron, a non-projection video display technology, was used at stadiums and concerts. Various thin-screen technologies are being developed, but only liquid crystal display (LCD), plasma display (PDP) and Digital Light Processing (DLP) have been publicly released. Recent technologies like organic light-emitting diode (OLED) as well as not-yet-released technologies like surface-conduction electron-emitter display (SED) or field emission display (FED) are in development to supersede earlier flat-screen technologies in picture quality.
Rear-projection television (RPTV) is a type of large-screen television display technology. Until approximately 2006, most of the relatively affordable consumer large screen TVs up to 100 in (250 cm) used rear-projection technology. A variation is a video projector, using similar technology, which projects onto a screen.
Visualplanet Ltd specialises in the manufacture and global distribution of projected capacitance interactive touch screen foils, which are designed to be used in a wide variety of Touch Screen applications from through-window touch to direct integration into LCD Screens. From its headquarters in Cambridge, England, the company distributes high quality products to an international network of partners.
A virtual touch screen (VTS) is a user interface system that augments virtual objects into reality either through a projector or optical display using sensors to track a person's interaction with the object. For instance, using a display and a rear projector system a person could create images that look three-dimensional and appear to float in midair. Some systems utilize an optical head-mounted display to augment the virtual objects onto the transparent display utilizing sensors to determine visual and physical interactions with the virtual objects projected.
A projection booth, projection box or Bio box is a room or enclosure for the machinery required for the display of movies on a reflective screen, located high on the back wall of the presentation space. It is common in a movie theater.