IAS Gyan

Daily News Analysis


13th July, 2023 Science and Technology

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Context: The Central Scientific Instruments Organisation (CSIO) in Chandigarh has completed a project to repair and refurbish periscopes on the Navy’s attack submarines. This is the first time that such a complex electro-optical device has been indigenously restored in India.


  • The project took 18 months to finish and involved studying and analysing various optical elements and components and developing the technology and methodology to meet the Navy’s specifications.
  • The Navy has 16 operational attack submarines of foreign origin. It has been looking for ways to overhaul and refurbish periscopes domestically for a long time and had approached the CSIO for this purpose.
  • India also has an ambitious indigenous programme to design and build its submarines. 6 nuclear-powered attack submarines (SSNs) under Project 75-A and six diesel-electric attack submarines (SSKs) under Project-75-I.


  • A periscope is a device that allows people to see things that are otherwise out of sight. It consists of a tube with mirrors or prisms at both ends, which reflect light from one end to the other.
  • It can change the direction of the line of sight by adjusting the angle of the mirrors or prisms. This allows the user to see around corners, over walls, or underwater.
  • It can magnify the image by using lenses or optical fibres. This makes the objects appear larger and clearer.
  • It can be used for observation, surveillance, or entertainment. For example, periscopes are often used in submarines to see above the water's surface without exposing themselves to enemy fire. They are also used in tanks, aircraft, and spacecraft for similar purposes.
  • They can be used for spying, spying on wildlife, or watching events from a different perspective.

Must-Read Articles:

PROJECT 75I: https://www.iasgyan.in/daily-current-affairs/project-75i-38


Q. What is the main function of a periscope?

1. To magnify distant objects

2. To measure angles and distances

3. To see things that are otherwise out of sight

4. To project images onto a screen

How many of the above statements is/are correct?

A) Only 1

B) Only 2

C) Only 3

D) All

Answer: B

Explanation: A periscope is a device that allows people to see things that are otherwise out of sight by reflecting light from one end to the other using mirrors or prisms. It can magnify the object with the help of lenses.