You might not think so, but basic computer keyboards have a surprising amount of engineering inside. We are not talking about incredible engineering like a rocket that can land itself or a stealth aircraft that can evade radar. Rather, we are talking about the engineering of cost reduction. Specifically, this keyboard has 8 critical parts inside, essentially removing all the components. so that you can buy them in bulk for as little as 1 dollar and 50 cents each. Engineering something that is durable, functional, and costs next to nothing is indeed a feat in its own right. So, let’s look inside this very cheap keyboard and see how only a few critical components enable it to work. After that, we’ll open a mechanical keyboard that costs over 50 times as much and see the difference, as well as find out what causes that clacking sound inside the mechanical keys.
I took a keyboard, which is expensive and assembled from 148 parts, and almost all the parts are the keys, screws, and the top and bottom plastic casing, leaving us only 8 critical parts inside. These components are a rubber sheet with domes under each key and three plastic sheets. The top button sheets have conductive wires printed on them, with dots under each key, and the middle sheet acts as a spacer with holes cut out of it. The remaining 4 components are 2 batteries, a bracket to clamp down the plastic sheets, and a small printed circuit board that has a simple microprocessor, a crystal oscillator, a switch, a 2.4 GHz planar antenna, a pair of wires to connect to the batteries, and a set of conductive lines to connect to the wires printed on the top and bottom plastic sheets. So, now that we have seen the few components inside,.
How do they work?
Well, the main idea is that the battery and microprocessor apply 3 volts to all the traces on the bottom sheet, while all the traces on the top sheet are actively monitored by the processor on the PCB. When a key is pressed, it presses on the rubber dome, which pushes the coonductive circle from the top sheet down through the air gap created by the middle sheet and into the circle on the bottom sheet, thereby breaking the connection between the top and bottom plastic sheets. The 3 volts
then travel along the conductive trace of the bottom sheet through the hole of the key that has been pressed and into the top sheet trace, and then return back to the PCB and microprocessor where they were sent. When you release your finger on the key, the rubber dome returns the key to the unpressed position by opening the connection. On the top sheet of plastic are 12 traces, and on the bottom sheet are 11 traces, with each tracing to a different set of keys. Its visually hard to see. There is a keyboard matrix.
How many types of keyboards are there?
There are 3 types of keyboards, which are mainly use
d. Mechanical, membrane and optical. Here we will discuss the pricing of a keyboard, how it feels to use it, its durability, sound, and customization. Lets start with pricing By far, membranes are the cheapest of the three because they are made out of a combination of plastic, polyester, silicone, and rubber.
When the key is pressed, it pushes the top layer down through a spacer layer of holes and interacts with the circuit at the bottom.
Mechanical switch work much differently.Mechanical switches have an actual metal switch that works a little bit like a button or a lever. So when you press it, it registers, and when you release it, that’s when the key gets stopped. That’s why mechanical keyboard accuracy, feel perception, and speed of a key press are completely in your control. The faster you click it, the faster you get registered.
As for optical keyboards, they look and feel just like mechanical keyboards. But it does operate differently. They use light induction to trigger the switches. When a switch is pressed, it blocks a light beam that is emitted by the PCB. And when this light beam is blocked, the actual key is registered. When you lift up the key and the light beam is no longer blocked, the key will stop being registered.
Now, I think you can imagine which ones are more expensive. Membrane keyboard tend to be much cheaper. Because its not hard to make, and making elements isn’t expensive. Then the second is mechanical keyboards. And the more expensive keyboard is optical keyboard.
How do I choose the right keyboard?
There are many types of keyboards. Full-size keyboards, compact keyboards, ten keyless keyboards, gaming keyboards, and more. You have to choose the keyboard based on how it works.
Full-size keyboards have more beneficial things. It has a numpad, which is the most important feature.
