Sometimes it can be useful to know a bit more about what goes on inside a product that you own. if you’re into birdwatching or some other hobby that requires binoculars, you might want to know how that piece of kit is made. Even if you’re not into something like that, you still might want to know. Thankfully, if you want to know a bit more about the history of these things and how they’re made—then you’re in the right place. We’re going to look a bit more closely into binoculars so you know exactly what you’re got in your hands when you next go birdwatching or plane spotting! So how are binoculars made?
How are binoculars made?
When looking at how binoculars are made, there are a few different aspects that play an important role, so we’re going to look at them in order. The raw materials could be thought of like the ingredients of a recipe, and better quality ingredients will make a better quality meal. That means you need better quality raw materials for the best pair of binoculars. Often, cheaper pairs will have lower quality raw materials and a more mass-market build quality. That’s why you get what you pay for. Aside from the raw materials, the manufacturing process is another important part. You might also want to know about the history of binocular manufacturing, as this has had a big influence on how they are made today.
What raw materials go into binoculars?
For a good quality pair of binoculars, you’ll need a range of high-quality raw materials. While poor manufacturing can make good materials into bad binoculars, you can’t really get a great pair of binoculars if you’re starting with bad raw materials. So what materials go into a pair of binoculars?
Older binoculars were so heavy and quite expensive because they used brass to house the units. This has been replaced more recently by hard-leather coverings which are much more affordable. Steel is also used for the strong parts of the housing, as well as aluminum for other metal parts. This made them cheaper to make and not as heavy. Optical glass is also an important part of a pair of binoculars.
How binoculars are made
Firstly, binoculars are normally designed using CAD and this helps with the production process. The eyepieces will be molded and cut using a diamond cutter, before being grinded and polished. They will then be carefully anodized and coated to stop them absorbing too much light.
These eyepieces will possibly go through another round of polishing and cutting and treating, this depends on how much care is being put into the manufacturing process and how high-quality the binoculars are intended to be.
The body of the binoculars is often made of aluminum which has been cast into shape. The eyepieces are put into this aluminum and coated once more in a plasma machine. This is important for high-performing binoculars.
The optics of the binoculars will then be tested extensively to make sure they’re working correctly. This will be done in special rooms that are free from any particles.
Rod-shaped prisms are then cut by lasers and coated with metal oxides in a vacuum chamber. While most of these processes can take place on a production line, the final assembly and checks are often done by hand for high-end binoculars. The left side of the unit must be made exactly parallel with the right side. The housing is then coated with a leather-like substance which is a bit more durable and flexible than actual leather. This is normally applied by hand with adhesive, and might have rubber coating added after.
The bare metal can then be coated with rubber as well, before the prisms are screwed in place by hand. Rubber eyecaps are then added, and the binoculars will then be waterproofed and chemicals like nitrogen are removed. The binoculars are then inspected and must pass final quality control protocols before being packed with their accessories and boxed.
During a regular quality control process, binoculars will be checked to be working underwater. Depending on the model of the binoculars, they might be expected to withstand pressure up to over 15m for five minutes.
The history of binocular manufacturing
Humans have been experimenting with the telescopic properties of glass for centuries, but things started becoming more serious thanks to Galileo Galilei who developed early prisms which original binocular telescopes are thought to be based on.
These early binoculars were obviously not the fine pieces of manufactured equipment that you’re used to today. They actually had lots of bubbles and imperfections thanks to less-developed manufacturing processes. The glass also used to go slightly green because it had too much iron in it, and crude polishing techniques lead to poor quality optics.
Hand-held binoculars started to come about in the Netherlands in the early 1700s, thanks to Johann Zahn’s designs.
A patent in 1854 from Ignatio Porro lead to the use of more advanced prisms as binoculars became more like the ones you see today. Further advances occurred in 1894 thanks to Carl Zeiss, who began correcting inverted images with more advanced prism systems.
The advance of materials and manufacturing processes lead to binoculars becoming more lightweight and easier to manufacture on a larger scale. Coatings and polishing techniques have continued to improve so that binoculars are now affordable and high-quality for almost everyone.
What have you used your binoculars for recently? There are so many possibilities thank to the advances in binocular manufacturing. Many people use their set of binoculars to enjoy their own hobbies or simply have a look at what’s out there—but they don’t realise how much work and thought has gone into making them. Now you know how serious the binocular manufacturing process is, you’ll be able to have new pride in your own set of binoculars.