General Studies Paper 3 (Science & Technology)
Question:- The Nobel Prize in Physics of 2014 was jointly awarded to Akasaki, Amano and Nakamura for the invention of Blue LEDs in the 1990s. How has this invention impacted the everyday life of human beings ? Answer in 250 words. 15 marks
May 26, 2022

Intro: Write generally about Nobel Prizes and Blue LEDs and explain the importance of Blue LEDs
Linkage Point: Create a room for introducing Body Paragraph
Body Paragraph-1 : Applications
Body Paragraph-2 : Concerns
Conclusion: Conclude by mentioning about government policies


INTRODUCTION: The Nobel Prizes are the awards given for intellectual achievement to those who have conferred the greatest benefit to mankind. LEDs (Light Emitting Diodes) are basically semiconductors that have been built in a way that they emit light when they’re activated. Different chemicals give different LEDs their colors. LEDs in green and red colors had been around for many years but since white light is produced by mixing the three primary colors – green, red and blue, the invention of Blue LEDs was a huge technical advancement. It required chemicals, including carefully-created crystals, that were very hard to make in the lab. Gallium nitride was the key ingredient used by the Nobel laureates in their ground-breaking blue LEDs.


LINKAGE POINT: This invention opened floodgates for several applications. Hence, it earned a Nobel Prize for the trio. Some of the most important applications of Blue LEDs are discussed below:



  1. 1. Energy efficiency : The previously used incandescent bulbs converted just 4% of electricity into light. But the modern white LED light bulbs have a conversion rate of more than 50 percent. Hence, they save money and electricity for all users to a greater extent than ever before.
  2. 2. A solar installation can charge an LED lamp to last a long time, hence it has become possible to provide light in far flung areas without electricity supply. This has benefitted households and helped small businesses to continue working after dark
  3.  3. LEDs have become an essential component in digital screens (computers, mobile phones) because they offer higher contrast than their predecessor technologies. The recent development of organic-LED offers flexibility in shaping the screens which is now widely used in wearable devices, smartphones etc.
  4. 4. LED offers great variation in size, their size range from few millimeters to several foots. It makes them compatible for wide range of application from circuit boards to home lighting. Also, the amount of light from LED can be varied, i.e., LEDs can very easily be dimmed by modulating the input current which was not possible in the earlier light bulbs.
  5. 5. Greater durability LEDs also last up to more hours as compared to fluorescent lights and incandescent bulbs. Switching more houses and buildings over to LEDs has significantly reduced the world’s electricity and materials consumption for lighting and holds greater potential in future. This in turn, reduces the amount of e-waste generated over time.
  6. 6. The light emitted by blue LEDs does not generate heat, which means it is safe to touch and can be used in close spaces where other types of lights may pose a risk.
  7. 7. Blue LED light is a non-chemical weapon capable of stunting the growth of herbicide-resistant weed seeds. Hence, they hold an immense potential for benefitting the agriculture sector.



  1. 1. Despite their benefits, blue LEDs only emit a narrow range of wavelengths that do not provide much visibility for seeing objects.
  2. 2. Blue light emitted from the screens of our gadgets is known to mess with circadian rhythm by suppressing the body’s ability to produce melatonin – the hormone responsible for drowsiness. Hence, an awareness needs to be generated amongst people about their side effects.



Blue was the last — and most difficult — advance required to create white LED light. The government of India, realizing their importance in energy conservation and provision, encouraged their use by promoting several schemes like UJJALA (Unnat Jyoti by Affordable LEDs for All) and Street Light National Programme. Thus, it is apt to say that Blue LEDs have revolutionized our lives.