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Periscope

technology Maturity 7-9 Next article →

A periscope is a clever tool for seeing. It helps people look over, around, or through things. This is useful when something blocks your view. For example, you might not be able to see directly in front of you.

Periscope simple
Periscope simple

A simple periscope uses an outer case with mirrors. These mirrors sit at a 45° angle to each other. They bounce light from an object down to your eye. Other versions use prisms, which are glass shapes that bend light.

Periskop linsen
Periskop linsen

Some complex versions even use fiber optics to show images.

How a periscope works depends on its design. A basic model uses two parallel mirrors to move light. More advanced ones use prisms or lenses to make things look clearer. Some periscopes even provide magnification. This means they make distant objects look much larger. A submarine periscope is often just two telescopes pointed at each other. If the two telescopes have different magnification levels, the image changes size. This allows a person to see things far away with great detail.

Many people helped improve the periscope over many years. In 1647, Johannes Hevelius described an early version. He called it a "polemoscope" and used lenses. Later, Mikhail Lomonosov made an "optical tube" that was very similar. In 1854, Hippolyte Marié-Davy invented a naval periscope using two small mirrors. By 1902, Simon Lake created a collapsible version for submarines. He called his invention the "omniscope." Sir Howard Grubb also worked to perfect the device during World War I.

Periscopes have been used in many important places. During World War I, soldiers used them in trenches. This let them see over the top without being in danger. Tanks also use them to protect the people inside. Instead of cutting holes in the armor, drivers use periscopes to look out.

1889 Arthur Krebs & Jean Rey periscope for the french Gymnote submarine
1889 Arthur Krebs & Jean Rey periscope for the french Gymnote submarine

In 1936, Rudolf Gundlach patented a rotating periscope. This allowed tank commanders to see in a full 360-degree circle. His design was used in many tanks, including the Polish 7-TP and the American Sherman.

Today, periscopes are still very important in science and the navy. Submarines use them to search for things at the surface. Modern submarine periscopes often use prisms instead of mirrors. Prisms are more rugged and can handle the water better. Some submarines even have two different scopes. One is for looking around, and the other is for targeting. Some very new submarines now use photonics masts. These use electronic sensors to send images to a screen instead of using a long tube.

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🖼️ Images & Media (3)
File:Periscope simple.svg
Periscope simple.svg
File:Periskop linsen.svg
Periskop linsen.svg
File:1889 Arthur Krebs & Jean Rey periscope for the french Gymnote submarine.jpg
1889 Arthur Krebs & Jean Rey periscope...
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