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Screen-door Effect
The screen-door effect (SDE) is a visual artifact of displays, where the fine lines separating pixels (or subpixels) become visible in the displayed image. This effect can be seen in digital projector images and regular displays under magnification or at close range, but the increases in display resolutions have made this much less significant. More recently, the screen-door effect has been an issue with virtual reality headsets and other head-mounted displays, because these are viewed at a much closer distance, and stretch a single display across a much wider field of view. SDE in projectors In LCD and DLP projectors, SDE can be seen because projector optics typically have significantly lower pixel density than the size of the image they project, enlarging these fine lines, which are much smaller than the pixels themselves, to be seen. This results in an image that appears as if viewed through a fine screen or mesh such as those used on anti-insect screen doors. The scre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microlens
A microlens is a small lens, generally with a diameter less than a millimetre (mm) and often as small as 10 micrometres (μm). The small sizes of the lenses means that a simple design can give good optical quality but sometimes unwanted effects arise due to optical diffraction at the small features. A typical microlens may be a single element with one plane surface and one spherical convex surface to refract the light. Because micro-lenses are so small, the substrate that supports them is usually thicker than the lens and this has to be taken into account in the design. More sophisticated lenses may use aspherical surfaces and others may use several layers of optical material to achieve their design performance. A different type of microlens has two flat and parallel surfaces and the focusing action is obtained by a variation of refractive index across the lens. These are known as gradient-index (GRIN) lenses. Some micro-lenses achieve their focusing action by both a variation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Display Technology
A display device is an output device for presentation of information in visual or tactile form (the latter used for example in tactile electronic displays for blind people). When the input information that is supplied has an electrical signal the display is called an '' electronic display''. Common applications for ''electronic visual displays'' are television sets or computer monitors. Types of electronic displays In use These are the technologies used to create the various displays in use today. * Liquid-crystal display (LCD) ** Light-emitting diode (LED) backlit LCD ** Thin-film transistor (TFT) LCD ** Quantum dot (QLED) display * Light-emitting diode (LED) display ** OLED display ** AMOLED display ** Super AMOLED display Segment displays Some displays can show only digits or alphanumeric characters. They are called segment displays, because they are composed of several segments that switch on and off to give appearance of desired glyph. The segments are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virtual Reality Sickness
Virtual reality sickness (VR sickness) occurs when exposure to a virtual environment causes symptoms that are similar to motion sickness symptoms. The most common symptoms are general discomfort, eye strain, headache, stomach awareness, nausea, vomiting, pallor, sweating, fatigue, drowsiness, disorientation, and apathy. Other symptoms include postural instability and retching. Common causes are low frame rate, input lag, and the vergence-accommodation-conflict. Virtual reality sickness is different from motion sickness in that it can be caused by the visually-induced perception of self-motion; real self-motion is not needed. It is also different from simulator sickness; non-virtual reality simulator sickness tends to be characterized by oculomotor disturbances, whereas virtual reality sickness tends to be characterized by disorientation. Consequences Virtual reality sickness may have undesirable consequences beyond the sickness itself. For example, Crowley (1987) argued th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uncanny Valley
The effect is a hypothesized psychological and aesthetic relation between an object's degree of resemblance to a human being and the emotional response to the object. The uncanny valley hypothesis predicts that an entity appearing almost human will risk eliciting eerie feelings in viewers. Examples of the phenomenon exist among robotics, 3D computer animations and lifelike dolls, and visuals produced by artificial intelligence. The increasing prevalence of digital technologies (e.g., virtual reality, augmented reality, and Unbiased rendering, photorealistic computer animation) has propagated discussions and citations of the "valley"; such conversation has enhanced the construct's verisimilitude. Etymology As related to robotics engineering, robotics professor Masahiro Mori (roboticist), Masahiro Mori first introduced the concept in 1970 from his book titled , phrasing it as . ''Bukimi no tani'' was literal translation, translated literally as ''uncanny valley'' in the 1978 boo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subpixel Rendering
Subpixel rendering is a method used to increase the effective resolution of a color display device. It utilizes the composition of each pixel, which consists of three subpixels of which are red, green, and blue that can each be individually addressable on the display matrix. Subpixel rendering is primarily used for text rendering on standard DPI displays. Despite the inherent color anomalies, it can also be used to render general graphics. History The origin of subpixel rendering as used today remains controversial. Apple Inc., IBM, and Microsoft patented various implementations with certain technical differences owing to the different purposes their technologies were intended for. Microsoft had several patents in the United States on subpixel rendering technology for text rendering on RGB Stripe layouts. The patents 6,219,025, 6,239,783, 6,307,566, 6,225,973, 6,243,070, 6,393,145, 6,421,054, 6,282,327, 6,624,828 were filed between October 7, 1998, and October 7, 1999, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silk Screen Effect
The silk screen effect (SSE) is a visual phenomenon seen in rear-projection televisions. SSE is described by viewers as seeing the texture of the television screen in front of the image. SSE may be found on all rear-projection televisions including DLP and Liquid Crystal on Silicon (LCoS). The effect is most visible when viewing bright white or very light colored images. Viewers also report seeing "sparkles" when viewing very bright colored images. SSE's nomenclature comes from the visual appearance of this effect, which is likened to viewing an image through a silk screen. SSE should not be confused with the screen door effect, another visual phenomenon seen in rear-projection televisions. Cause of SSE SSE is caused by textured screens used in most rear-projection televisions. Rear-projection television manufacturers use textured screens to increase the viewing angle of the television. Reducing SSE SSE can be reduced by properly calibrating the picture controls of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scan Line
A scan line (also scanline) is one line, or row, in a raster scanning pattern, such as a line of video on a cathode-ray tube (CRT) display of a television set or computer monitor. On CRT screens the horizontal scan lines are visually discernible, even when viewed from a distance, as alternating colored lines and black lines, especially when a progressive scan signal with below maximum vertical resolution is displayed. This is sometimes used today as a visual effect in computer graphics. The term is used, by analogy, for a single row of pixels in a raster graphics image. Scan lines are important in representations of image data, because many image file formats have special rules for data at the end of a scan line. For example, there may be a rule that each scan line starts on a particular boundary (such as a byte or word; see for example BMP file format). This means that even otherwise compatible raster data may need to be analyzed at the level of scan lines in order to conver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pancake Lens
A pancake lens is a colloquial term for a flat, thin camera lens assembly (short barrel). The majority are prime lenses of a Normal lens, normal or slightly wider angle of view, but some are zoom lenses. Motivation Pancake lenses are primarily valued for providing quality optics in a compact package. The resulting camera and lens assembly may even be small enough to be pocketable, a design feature which is usually impractical with conventional Single-lens reflex camera, SLR bodies and lens assemblies. Pancake lenses can be very short and flat because they do not need large amounts of optical correction, i.e. extra lens elements. The problem arises when such lenses have too short a focal length to fit in front of the retractable mirrors used in reflex cameras. In such a situation, a pancake lens focuses in front of, rather than on, the focal plane (film or light sensor) of the camera. This has necessitated the design of retrofocus lenses that refocus the image farther back, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pixelization
Pixelization (in British English pixelisation) or mosaic processing is any technique used in editing images or video, whereby an image is blurred by displaying part or all of it at a markedly lower resolution. It is primarily used for censorship. The effect is a standard graphics filter, available in all but the most basic bitmap graphics editors. In media Pixelization has also been used for artistic effect, notably in the art print ''The Wave of the Future'', a reinterpretation of Katsushika Hokusai's '' The Great Wave off Kanagawa''. In this updated print, the image of the large ocean wave shifts from the traditional style of the Japanese woodcut print to a pixelized image and finally to a wireframe model computer graphics image. ''Westworld'' (1973) was the first feature film to use digital image processing to pixelize photography to simulate an android's point of view. The 2010 third-person cover shooter Kane & Lynch 2: Dog Days also used pixelization for artistic purpo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Artifact
Visual artifacts (also artefacts) are anomalies apparent during visual representation as in digital graphics and other forms of imagery, especially photography and microscopy. In digital graphics * Image quality factors, different types of visual artifacts * Compression artifacts * Digital artifacts, visual artifacts resulting from digital image processing * Noise * Screen-door effect, also known as fixed-pattern noise (FPN), a visual artifact of digital projection technology * Ghosting (television) *Screen burn-in * Distortion * Silk screen effect * Rainbow effect * Screen tearing * Moiré pattern * Color banding In video entertainment Many people who use their computers as a hobby experience artifacting due to a hardware or software malfunction. The cases can differ but the usual causes are: * Temperature issues, such as failure of cooling fan. * Unsuited video card (graphics card) drivers. * Drivers that have values that the graphics card is not suited with. * Overcl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
