I always wondered how electronic sensors work. I mean, there is some kind of analogue sensor that detects a value that is not quantifiable (temperature, pressure, speed etc.). How exactly does conversion from analogue detector get transformed to some kind of numeric value that gets shown to user?
In: Engineering
Sensing real world phenomenon is inherently analog. Once that analog value is read, it then has to be converted into a digital signal via an analog-to-digital converter.
There are many ways ADC can be implemented.
However, a good way to understand the principle would be to imagine I’ve got a stick hidden behind my back and you want to know how long it is. You can ask me yes/no questions to get the answer.
For example, you could ask me “is it between 6 and 7 inches?” followed by “is it between 7 and 8 inches”… and so forth until I answer yes. Indeed, you could get a bunch of friends and you could all ask me questions about the entire range simultaneously if you wanted to speed up the process.
Or you could ask questions like “is it bigger than 6 inches?” and, depending on the answer, “is it bigger than 9 inches?” or “is it bigger than 3 inches?”.
If you asked enough questions, you’re eventually going to get the answer to any arbitrary level of precision you desire.
All those ‘yes/no’ answers are bits in a digital number.
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