A Notification LED is a small
RGB or
monochrome
A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, monochr ...
LED
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (cor ...
light usually present on the front-facing screen
bezel
Bezel may refer to:
Object
* Bezel (jewellery), the rim which encompasses and fastens a jewel, watch crystal, lens or other object
* Bezel, the sloping facets of the crown of a cut gem after gem cutting
* Screen bezel, a space or frame around a d ...
(display side) of
smartphone
A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...
s and
feature phone
A feature phone (also spelled featurephone) is a type or class of mobile phone that retains the form factor of earlier generations of mobile telephones, typically with press-button based inputs and a small non-touch display. They tend to use an ...
s whose purpose is to blink or pulse to notify the phone user of missed calls, incoming
SMS
Short Message/Messaging Service, commonly abbreviated as SMS, is a text messaging service component of most telephone, Internet and mobile device systems. It uses standardized communication protocols that let mobile devices exchange short text ...
messages, notifications from other apps, low battery warning, etc., and optionally to facilitate locating the mobile phone in darkness.
[ Versus: For and against LED notification lights in phones]
/ref> It usually pulses in a continuous way to draw the attention of the user. It is a part of the device's notification system In information technology, a notification system is a combination of software and hardware that provides a means of delivering a message to a set of recipients. It commonly shows activity related to an account. Such systems constitute an important ...
that uses a cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may ...
-powered push
Push may refer to:
Music
* Mike Dierickx (born 1973), a Belgian producer also known as Push
Albums
* ''Push'' (Bros album), 1988
* ''Push'' (Gruntruck album), 1992
* ''Push'' (Jacky Terrasson album), 2010
Songs
* "Push" (Enrique Iglesias ...
notification service to relay remote notification messages to the user, or local notifications. Similar to audio notifications, a notification LED is a very battery-efficient way to inform the user of new notifications without turning on the screen at all.
Overview
In any mobile phone
A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive telephone call, calls over a radio freq ...
or smartphone, battery life is an important consideration and the display is the component that consumes the maximum battery when it is fully lit up. In regular usage, a user may only want to briefly turn on his or her phone to check if anything requires attention.
By blinking unobtrusively, the notification LED light discreetly conveys to the user of any potentially important message or call. [Customize Your Android Phone's Colored LED Notification Light]
This way, the whole display does not have to be turned on every time a message arrives, thus saving the battery. When the user is away from the phone or when the phone is in silent mode, the blinking LED can effectively convey the user that some action is needed. Conversely, if the light does not blink, then it conveys to the user that there is no unread message or notification that requires his or her attention, again saving battery and the user's time and effort required to unlock the device, and check for new messages.
In some phones, the LED notification light is also sometimes designed to glow red when the battery is low, when the battery is charging and turn green when the battery is fully charged. This saves the user the hassle of turning on the screen to check the battery percentage.
While most phones include the notification LED light on the front side, some smartphone manufacturers like LG or Nokia have also integrated it into the power button, while some phones from Motorola, Xiaomi, Razer or ASUS have their brand logo on the back side of the phone, serving as the notification light. [ Latest Motorola One Zoom renders reveal unique light-up rear logo]
Customization based on app
In some Android and BlackBerry
The blackberry is an edible fruit produced by many species in the genus ''Rubus'' in the family Rosaceae, hybrids among these species within the subgenus ''Rubus'', and hybrids between the subgenera ''Rubus'' and ''Idaeobatus''. The taxonomy of ...
smartphones, the notification LED light's behavior could be customized per app, so that, each color would indicate a different app. Apps like WhatsApp
WhatsApp (also called WhatsApp Messenger) is an internationally available freeware, cross-platform, centralized instant messaging (IM) and voice-over-IP (VoIP) service owned by American company Meta Platforms (formerly Facebook). It allows user ...
or Telegram
Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas ...
also include a setting to set this color for the LED light.
Alternative always on display feature
light
The notification LED light was popular when feature phone
A feature phone (also spelled featurephone) is a type or class of mobile phone that retains the form factor of earlier generations of mobile telephones, typically with press-button based inputs and a small non-touch display. They tend to use an ...
s were widely used. In early smartphones running Windows Mobile
Windows Mobile is a discontinued family of mobile operating systems developed by Microsoft for smartphones and personal digital assistants.
Its origin dated back to Windows CE in 1996, though Windows Mobile itself first appeared in 2000 as Pock ...
or the Android operating system, the LED notification light was also a fairly common feature. These smartphones usually had LCD displays, so without the LED present, the entire backlight behind the display would need to be turned on to check for any new notifications.
Gradually, the smartphone industry has been moving towards OLED
An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light ...
displays. With this transition, the dedicated notification LED light has slowly been eliminated from newer smartphones. There is also a focus by smartphone designers to minimize the screen bezels or keep them very thin, thus leaving no room for the notification LED light.
As a replacement for the LED light, some smartphones from Samsung, LG, Nokia include an Always On Display feature. On OLED displays, the Always-On Display (AOD) shows limited information while the phone is asleep, that is, when the entire display is not lit up. With OLED screens, only a part of the screen, or a few pixels on it can be turned on to convey information.
With any pixel on an OLED screen effectively being a notification LED, software can be used to customize its appearance. It can blink or pulse like a light continuously, or some phone manufacturers light up the display's pixels like a ring or have edge lighting.
References
Mobile phones
{{DEFAULTSORT:Notification System
Human–computer interaction
Information systems