An electronic device that is used as a very effective light source is known as light emitting diode or LEDs. These diodes are used to make up a video display which is known as LED display. LEDs are used in everyday devices ranging from remote control to traffic lights. LED display is also used in store signs and billboards.
LED panels are used for illumination rather than displaying purposes. An LED panel consists of number of LEDs and a typical LED display consists of many LED panels. Surface mounted device (SMD) panel and conventional LED panel are the two panels of LED panels found in the market. The conventional panel uses discrete LEDs which are typically used for display screens in large outdoors. Conventional panels are more common as compared to others and in this type of panel, the cluster of LEDs of different color are grouped to form a square-shaped pixels used for displaying.
The LED displays which are used indoors make use of SMD technology. SMD technology utilizes red, green and blue LEDs in panel which are themselves used to form lighting and illumination but not for display. Pixels are formed mounted over circuit boards and chips. The pixels formed are smaller than a pinhead. Therefore in SMD, the maximum viewing distance is decreased as well as there is slight decrease in the brightness. The both above mentioned featured make the SMD technology better for indoor applications.
The LEDs used to make up an LED display are one of the most important technologies of electronics. The light emitting diode offers many advantages over other light emitting sources. This diode is made of a semiconductor chip surrounded by the transparent plastic case. The plastic case allows the light to pass through it. As positive and negative terminals of the diode is connected to the supply, the electrons starts following through the semiconductor due to its chemical nature. The collision of electrons emits energy in the form of photons or light. The emission of different colors including infrared and ultraviolet light depends on the semiconductor material used in the diode.
Nowadays, LEDs are preferred over traditional light sources due to many advantages over them. In traditional light sources a large amount of heat is produced and nearly half of energy is wasted in the form of heat. On the other hand, LED consumes very less energy and very less amount of heat is produced as compared to traditional light sources. These are the reasons for which the LEDs are used in traffic lights and all other devices.
The first LED display was monochromatic because at that time there was no efficient blue light LED. The inventors of the first LED display screen were recognized and receive awards at 29th Engineering Exposition held in Anaheim, California. The first LED display was developed in late 1970s and after the development of the effective blue LEDs, the color displays were emerging in early 1990s.