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Reticle

technology Maturity 7-9 Next article →

A reticle is a pattern of fine lines or markings.

Reticles vector
Reticles vector

These patterns sit inside the eyepiece of many optical tools. You might find them in a telescopic sight, a microscope, or even a spotting scope. They provide a reference for people to use during visual inspections. This helps them measure or aim with great care. The name comes from the Latin word reticulum, which means a small net.

PocketComparator2
PocketComparator2

There are many different ways a reticle can work. The most basic type is called a crosshair. This is just two lines that cross like a plus sign. Some reticles use dots, circles, or even horseshoe shapes.

Findot reticle
Findot reticle

Some modern versions use a duplex design. This means the bars are thick on the outside but thin in the middle. The thick parts help your eye find the center quickly. The thin parts allow for very precise aiming.

People have used many different materials to make these lines over time. In the past, makers used hair or spiderweb. Spider silk from a brown recluse spider was especially good because it is very thin and strong.

ПД-8 (ПД-8А)
ПД-8 (ПД-8А)

Later, Philippe de La Hire suggested using etched glass in the year 1700. This method uses a diamond point to engrave lines onto a glass plate. Today, many reticles are made of wire or even digital images on a screen.

USGsight01
USGsight01

History shows us that many people helped develop these tools. The reticle is often linked to Robert Hooke in the 17th century. However, an astronomer named William Gascoigne might have invented it even earlier.

Pso-1onsvd
Pso-1onsvd

Some reticles are even designed to help people measure distance. A 30/30 reticle has thin bars that span 30 minutes of arc. This helps a shooter know how far away an object is. This is much better than just making a guess.

Reticles help us understand the world around us in many ways. Astronomers use them to look at the stars and planets. Some telescopes use a special tool called a filar micrometer to measure distances between stars.

Reflector reflex sight diagram 3
Reflector reflex sight diagram 3

Surveyors use them to map out land and buildings. Even the stars themselves honor this tool. There is a constellation named Reticulum to recognize the reticle and its help in astronomy. It is a small but vital part of how we see clearly.

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🖼️ Images & Media (8)
File:Pso-1onsvd.jpg
Pso-1onsvd.jpg
File:Reticles vector.svg
Reticles vector.svg
File:20090906 022641 Algae.jpg
20090906 022641 Algae.jpg
File:PocketComparator2.JPG
PocketComparator2.JPG
File:ПД-8 (ПД-8А).jpg
ПД-8 (ПД-8А).jpg
File:Findot reticle.svg
Findot reticle.svg
File:USGsight01.jpg
USGsight01.jpg
File:Reflector reflex sight diagram 3.png
Reflector reflex sight diagram 3.png
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