liquid-crystal display
A liquid-crystal display (LCD) is a flat-panel display
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 equipmen ...
(LCD) with an optical layer that reflects and transmits light (''transflective'' is a
portmanteau
A portmanteau word, or portmanteau (, ) is a blend of wordscontrast being constant with
illuminance
In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness ...
. However, under dim and dark ambient situations the light from a
backlight
A backlight is a form of illumination used in liquid crystal displays (LCDs). As LCDs do not produce light by themselves—unlike, for example, cathode ray tube (CRT), plasma (PDP) or OLED displays—they need illumination ( ambient light or a ...
is transmitted through the transflective layer to provide light for the display. The transflective layer is called a transflector. It is typically made from a sheet polymer. It is similar to a
one-way mirror
A one-way mirror, also called two-way mirror (or one-way glass, half-silvered mirror, and semi-transparent mirror), is a reciprocal mirror that appears reflective on one side and transparent at the other. The perception of one-way transmission i ...
but is not
specular
Specular reflection, or regular reflection, is the mirror-like reflection of waves, such as light, from a surface.
The law of reflection states that a reflected ray of light emerges from the reflecting surface at the same angle to the surfac ...
.
An application is digital LCD
wristwatches
A watch is a portable timepiece intended to be carried or worn by a person. It is designed to keep a consistent movement despite the motions caused by the person's activities. A wristwatch is designed to be worn around the wrist, attached by ...
. In dim ambient light or at night a backlight allows reading of the display in its transmissive mode.: W. Boller, M. Donati, J. Fingerle, P. Wild, ''Illuminating Arrangement for a Field-Effect Liquid-Crystal Display as well as Fabrication and Application of the Illuminating Arrangement'', filed Oct. 15, 1976. Digital time displays in
alarm clocks
An alarm clock (or sometimes just an alarm) is a clock that is designed to alert an individual or group of individuals at a specified time. The primary function of these clocks is to awaken people from their night's sleep or short naps; they ar ...
for bedrooms may also work this way. If they are battery-powered, the backlight may be push-button operated. The backlighting is usually dim, so that the display is comfortably readable at night. Some 21st century
smartwatch
A smartwatch is a wearable computer in the form of a watch; modern smartwatches provide a local touchscreen interface for daily use, while an associated smartphone app provides management and telemetry, such as long-term biomonitoring. While ea ...
es such as the Pebble Smartwatch and the Amazfit Stratos also use transflective LCDs.
When an illuminance sensor is added for control of the backlight, such a transflective LCD can be read over a wide range of illuminance levels. This technique is often found in automotive instrumentation. In portable electronic devices the transflective mode of operation helps to save battery charge, since in bright environments no
backlight
A backlight is a form of illumination used in liquid crystal displays (LCDs). As LCDs do not produce light by themselves—unlike, for example, cathode ray tube (CRT), plasma (PDP) or OLED displays—they need illumination ( ambient light or a ...
ing is required.
Some displays that transmit light and have minor reflectivity are best readable in the dark and fairly readable in bright sunlight, but only under a particular angle; they are least readable in bright daylight without direct sunlight.
Trade names
Display manufacturers label their transflective screens under a variety of trade names:
* BE+: SolarbON
* Boe Hydis: Viewiz
* Motion Computing: View Anywhere
*
LG Display
LG Display (Korean: LG 디스플레이) is one of the world's largest manufacturers and supplier of thin-film transistor liquid crystal display (TFT-LCD) panels, OLEDs and flexible displays. LG Display is headquartered in Seoul, South Korea, a ...
: Shine-Out
*
NEC Displays
is a Japanese multinational information technology and electronics corporation, headquartered in Minato, Tokyo. The company was known as the Nippon Electric Company, Limited, before rebranding in 1983 as NEC. It provides IT and network soluti ...
Panasonic
formerly between 1935 and 2008 and the first incarnation of between 2008 and 2022, is a major Japanese multinational corporation, multinational Conglomerate (company), conglomerate corporation, headquartered in Kadoma, Osaka, Kadoma, Osaka P ...
: CircuLumin
*
Dell
Dell is an American based technology company. It develops, sells, repairs, and supports computers and related products and services. Dell is owned by its parent company, Dell Technologies.
Dell sells personal computers (PCs), servers, data ...
: DirectVue or DirectView.
*
Motorola Mobility
Motorola Mobility LLC, marketed as Motorola, is an American consumer electronics manufacturer primarily producing smartphones and other mobile devices running Android OS, Android. It is a subsidiary of the Chinese multinational technology company ...
: AnyLight
*
Pebble (watch)
Pebble is a discontinued smartwatch developed by Pebble Technology Corporation. Funding was conducted through a Kickstarter campaign running from April 11, 2012, to May 18, 2012, which raised $10.3 million; it was the most funded project in Kick ...
High brightness monitor
A high brightness monitor, also known as a sunlight readable monitor or VHB (very high brightness) monitor is a computer monitor designed to operate in very bright environments, for example in broad daylight. Sunlight Readable monitors typically ...