A B C D E F G H I J K L M N O P Q R S T U V W X Y Z _
| Refresh Rate | The number of times in a second that display hardware draws the data, refreshing the image. Refresh rates for broadcast TV vary by region – for example, European HD systems run at 50 Hz. On CRT displays, increasing the refresh rate decreases flickering, thereby reducing eye strain. However, if a refresh rate is specified that is beyond what is recommended for the display, damage to the display can occur. Refresh Rate is distinct from the measure of frame rate in that the refresh rate includes the repeated drawing of identical frames, while frame rate measures how often a video source can feed an entire frame of new data to a display. |
| RCA Plug | A type of electrical connector commonly used to carry audio and video signals. In the most normal usage, cables have a standard plug on each end, consisting of a central male connector, surrounded by a ring. Devices mount the jack, consisting of a central hole with a ring of metal around it. Plugs and sockets on consumer equipment are conventionally colour-coded to aid correct connections. For example yellow for composite video, red for the right channel, and white or black for the left channel of stereo audio. This trio (or pair) of jacks can be found on the back of almost all audio and video equipment. The name 'RCA' derives from the Radio Corporation of America, which introduced the design by the early 1940s to allow mono phonograph players to be connected to amplifiers. RCA Plugs are also commonly referred to as Phono Plugs. |
| RF Connector | An electrical connector designed to work at radio frequencies in the multi-megahertz range. RF connectors are typically used with coaxial cables and are designed to maintain the shielding that the coaxial design offers. Better models also minimise the change in transmission line impedance at the connection. |
| RGB+HV | A RGB signal where the synchronisation impulses that keep the picture fully synchronised (all colours at the right time) are found in separate cables. RGB has three wires and HV adds two more wires. |
| RGB | A colour model in which Red, Green, and Blue light are added together in various ways to reproduce a broad array of colours. Computer monitors and TVs emit colour as RGB light. Although all colours of the visible spectrum can be produced by merging red, green and blue light, monitors are capable of displaying only a limited gamut of the visible spectrum. Typical RGB input devices are colour TV and video cameras, image scanners, and digital cameras. Typical RGB output devices are TV sets (CRT, LCD, plasma, etc.), computer and mobile phone displays, and video projectors. Colour printers, on the other hand, are not RGB devices, but subtractive colour devices - typically CMYK colour model where secondary colours (cyan, magenta and yellow) are used to simulate the colours required, with black (K) added to help CMY reproduce rich blacks and shadows. |
| RF | Radio frequency (RF) radiation is a subset of electromagnetic radiation with a wavelength of 100 km to 1 mm, which is a frequency of 3 kHz to 300 GHz, respectively. This range of electromagnetic radiation constitutes the radio spectrum and corresponds to the frequency of alternating current electrical signals used to produce and detect radio waves. RF can refer to electromagnetic oscillations in either electrical circuits or radiation through air and space. Like other subsets of electromagnetic radiation, RF travels at the speed of light. |
| Resistive Touchscreen | Resistive touchscreens are composed of two flexible sheets coated with a resistive material and separated by an air gap or microdots. When contact is made to the surface of the touchscreen, the two sheets are pressed together, registering the precise location of the touch. Because the touchscreen responds to pressure on its surface, contact can be made with a finger or any other pointing device. Resistive touchscreens typically have high resolution (4096 x 4096 DPI or higher), providing accurate touch control. |