In the broadest definition, a sensor is a device, module, machine, or subsystem whose purpose is to detect events or changes in its environment and send the information to other electronics, frequently a computer processor. A sensor is always used with other electronics.
Sensors are used in everyday objects such as touch-sensitive elevator buttons (tactile sensor) and lamps which dim or brighten by touching the base, besides innumerable applications of which most people are never aware. With advances in micromachinery and easy-to-use microcontroller platforms, the uses of sensors have expanded beyond the traditional fields of temperature, pressure or flow measurement, for example into MARG sensors. Moreover, analog sensors such as potentiometers and force-sensing resistors are still widely used. Applications include manufacturing and machinery, airplanes and aerospace, cars, medicine, robotics and many other aspects of our day-to-day life. There are a wide range of other sensors, measuring chemical & physical properties of materials. A few examples include optical sensors for Refractive index measurement, vibrational sensors for fluid viscosity measurement and electro-chemical sensor for monitoring pH of fluids.
A sensor's sensitivity indicates how much the sensor's output changes when the input quantity being measured changes. For instance, if the mercury in a thermometer moves 1 cm when the temperature changes by 1 °C, the sensitivity is 1 cm/°C (it is basically the slope dy/dx assuming a linear characteristic). Some sensors can also affect what they measure; for instance, a room temperature thermometer inserted into a hot cup of liquid cools the liquid while the liquid heats the thermometer. Sensors are usually designed to have a small effect on what is measured; making the sensor smaller often improves this and may introduce other advantages.Technological progress allows more and more sensors to be manufactured on a microscopic scale as microsensors using MEMS technology. In most cases, a microsensor reaches a significantly faster measurement time and higher sensitivity compared with macroscopic approaches. Due to the increasing demand for rapid, affordable and reliable information in today's world, disposable sensors—low-cost and easy‐to‐use devices for short‐term monitoring or single‐shot measurements—have recently gained growing importance. Using this class of sensors, critical analytical information can be obtained by anyone, anywhere and at any time, without the need for recalibration and worrying about contamination.
I'm wondering what are the pros and cons of the CNT sensors and conventional gas detectors?
I know that CNT sensors can detect very low chemical adsorption energy, which a conventional gas detector probably can't.
Besides that, is there any more pros and cons of the two?
Thanks!
Hey, I'm new to these forums and am just learning about quantum physics.
I was wondering about the detectors used to pick up on photons. How exactly do these detectors work? What about the ones described which detect a photon but allow it pass through?
Also, if a detector were designed...
I was reading something today about it being stupid to own a radar detector in Australia because the police carry radar detector detectors with them. Is this even possible?
I would have assumed that radar detectors don't send out a signal of sorts but only attempt to detect incoming radar...
There's a square detector of area A. When a point source is placed at the center of this detector, half of the emitted particles are detected. What fraction of the particles are detected when the point source is placed a distance x away?
I figured that at x=0, 50% of the particles are...
I just noticed my new $10 smoke detector contains a few microcuries or less of radioactive Americium. Anyone one knows how these work? Why this element? It's the first time I see an application for it.