An electronic calculator is typically a portable electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics.
A liquid-crystal display (LCD) is a flat-panel display or other electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers. Liquid crystals do not emit light directly, instead using a backlight or reflector to produce images in color or monochrome. LCDs are available to display arbitrary images or fixed images with low information content, which can be displayed or hidden. For instance: preset words, digits, and seven-segment displays, as in a digital clock, are all good examples of devices with these displays. They use the same basic technology, except that arbitrary images are made from a matrix of small pixels, while other displays have larger elements. LCDs can either be normally on (positive) or off (negative), depending on the polarizer arrangement. For example, a character positive LCD with a backlight will have black lettering on a background that is the color of the backlight, and a character negative LCD will have a black background with the letters being of the same color as the backlight. Optical filters are added to white on blue LCDs to give them their characteristic appearance.
A Nixie tube, or cold cathode display, is an electronic device used for displaying numerals or other information using glow discharge.
A cold cathode is a cathode that is not electrically heated by a filament. A cathode may be considered "cold" if it emits more electrons than can be supplied by thermionic emission alone. It is used in gas-discharge lamps, such as neon lamps, discharge tubes, and some types of vacuum tube. The other type of cathode is a hot cathode, which is heated by electric current passing through a filament. A cold cathode does not necessarily operate at a low temperature: it is often heated to its operating temperature by other methods, such as the current passing from the cathode into the gas.
A flat-panel display (FPD) is an electronic display used to display visual content such as text or images. It is present in consumer, medical, transportation, and industrial equipment.
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 vacuum fluorescent display (VFD) is a display device once commonly used on consumer electronics equipment such as video cassette recorders, car radios, and microwave ovens.
A seven-segment display is a form of electronic display device for displaying decimal numerals that is an alternative to the more complex dot matrix displays.
A fourteen-segment display (FSD) is a type of display based on 14 segments that can be turned on or off to produce letters and numerals. It is an expansion of the more common seven-segment display, having an additional four diagonal and two vertical segments with the middle horizontal segment broken in half. A seven-segment display suffices for numerals and certain letters, but unambiguously rendering the ISO basic Latin alphabet requires more detail. A slight variation is the sixteen-segment display which allows additional legibility in displaying letters or other symbols.
A sixteen-segment display (SISD) is a type of display based on sixteen segments that can be turned on or off to produce a graphic pattern. It is an extension of the more common seven-segment display, adding four diagonal and two vertical segments and splitting the three horizontal segments in half. Other variants include the fourteen-segment display which does not split the top or bottom horizontal segments, and the twenty two-segment display that allows lower-case characters with descenders.
A thin-film-transistor liquid-crystal display is a variant of a liquid-crystal display that uses thin-film-transistor technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.
Handheld electronic games are very small, portable devices for playing interactive electronic games, often miniaturized versions of video games. The controls, display and speakers are all part of a single unit. Rather than a general-purpose screen made up of a grid of small pixels, they usually have custom displays designed to play one game. This simplicity means they can be made as small as a smartwatch, and sometimes are. The visual output of these games can range from a few small light bulbs or LED lights to calculator-like alphanumerical screens; later these were mostly displaced by liquid crystal and vacuum fluorescent display screens with detailed images and in the case of VFD games, color. Handhelds' popularity was at its peak from the late 1970s into the early 1990s before declining. They are the precursors to the handheld game console.
An electronic component is any basic discrete device or physical entity in an electronic system used to affect electrons or their associated fields. Electronic components are mostly industrial products, available in a singular form and are not to be confused with electrical elements, which are conceptual abstractions representing idealized electronic components and elements.
A digital clock is a type of clock that displays the time digitally, as opposed to an analogue clock.
A dot-matrix display is a low cost electronic digital display device that displays information on machines such as clocks, watches, calculators, and many other devices requiring a simple alphanumeric display device of limited resolution.
The twisted nematic effect (TN-effect) was a main technology breakthrough that made LCDs practical. Unlike earlier displays, TN-cells did not require a current to flow for operation and used low operating voltages suitable for use with batteries. The introduction of TN-effect displays led to their rapid expansion in the display field, quickly pushing out other common technologies like monolithic LEDs and CRTs for most electronics. By the 1990s, TN-effect LCDs were largely universal in portable electronics, although since then, many applications of LCDs adopted alternatives to the TN-effect such as in-plane switching (IPS) or vertical alignment (VA).
A vane display is a type of 7-segment display. Unlike LED and VFD segmented displays, vane displays are composed of seven physical surfaces (vanes), typically painted white, but occasionally other colors, such as yellow or fluorescent green. If a segment is to be displayed as "off", it will be rotated so that its edge faces forward, with the painted surface pointing away and not visible. A segment that is to be displayed as "on" will be rotated so that the painted surface is shown.
Electrically operated display devices have developed from electromechanical systems for display of text, up to all-electronic devices capable of full-motion 3D color graphic displays. Electromagnetic devices, using a solenoid coil to control a visible flag or flap, were the earliest type, and were used for text displays such as stock market prices and arrival/departure display times. The cathode ray tube was the workhorse of text and video display technology for several decades until being displaced by plasma, liquid crystal (LCD), and solid-state devices such as thin-film transistors (TFTs), LEDs and OLEDs. With the advent of metal-oxide-semiconductor field-effect transistors (MOSFETs), integrated circuit (IC) chips, microprocessors, and microelectronic devices, many more individual picture elements ("pixels") could be incorporated into one display device, allowing graphic displays and video.
Polarizing organic photovoltaics (ZOPV) is a concept for harvesting energy from Liquid crystal display screens, developed by engineers from UCLA. This concept enables devices to use external light and the LCD screen's backlight using photovoltaic polarizers. Photovoltaic polarizers convert this light into electricity which can be used to power the device. This concept also provides multifunctional capability to devices with LCD screens as they act as photovoltaic devices and also as polarisers.
