The Ultimate LED Technology Quiz

Characteristics and History of LEDs

• A key characteristic of LEDs is their compact size, which allows for flexibility in design and use.
• LEDs were first invented in 1962.

Color Emission and Production

• The color of the light emitted by an LED is determined by the semiconductor material used.
• GaN (gallium nitride) is a common material used as the substrate for LED production.
• Patterned wafers used in LED production are referred to as epi-wafers.
• In the late 1980s, the introduction of GaAlAs (gallium aluminum arsenide) provided an efficient source of red and amber LEDs.
• The development of InGaN (indium gallium nitride) technology opened up possibilities for big LED video displays by introducing blue and later green LEDs.

Companies and Innovations

• The first practical LED display was developed by Texas Instruments.
• Fairchild Semiconductor was the first company to mass-produce visible LEDs.
• Texas Instruments announced the first commercial LED product, the HP Model 5082-7000 Numeric Indicator, which replaced the Nixie tube.
• Hewlett-Packard (HP) introduced the first LED device to use integrated circuit technology.
• Apple, Samsung, and Sony are currently developing MicroLED displays.

Scientists and Awards

• Oleg Losev discovered near-infrared light emission from a tunnel diode on a GaAs substrate.
• Shuji Nakamura demonstrated the first blue electroluminescence from zinc-doped gallium nitride and was awarded the Nobel Prize in Physics for the invention of an efficient gallium nitride blue LED.

Advantages and Disadvantages

• The main advantage of LEDs over incandescent light sources is their compact size and flexibility.
• A disadvantage of LEDs compared to incandescent lamps is their limited heat dissipation capability.