Hi R2D2 - great question! Air is essentially a mixture of gases. Most gases are transparent to infrared cameras and the camera sees right through them. Infrared cameras typically only see infrared radiation from a sold surface. There are exceptions to that though. For example, for a significant distance, water vapors will attenuate the infrared radiation.
@@movitherm Question, what would happen if an object was covered by a material that made it invisible? like the new technology developed by several militaries
I don’t believe this fully answered the question. what is an infrared camera made of? how does each element detect heat? how can the heat be recorded and digitized?
There are different infrared camera detector technologies available. Each one works a bit different. We essentially differentiate two main categories, micro-bolometer type detectors and quantum well based detectors. The micro-bolometer type has tiny thermocouple elements as pixels that change resistance based on the infrared radiation it is exposed to. The quantum well type actually measures photons in the infrared wavebands. Either the change in resistance or the amount of photons captures is then digitized into a digital count. Some magic sauce is used to convert infrared radiation into temperature and on the software side you can now measure temperature.
@@movitherm bruh put this in the video with visuals so everyone can understand. Why give visuals for the simple part then boring paragraphs for the RELEVANT but complicated and boring part😑
Search "How do Camcorders work?" I have read the creator's reply and it seems to be that. I am a student and i am learning, if i made a mistake, kindly inform me and explain it to me.
You have said that the detector sees the infrared radiation. But where does this comes from? Does the bike(or any object) emits the infrared radiation or we from the camera incident any light or etc., to reflect it back and measure with it?
The infrared radiation comes from the heat of the particles. Let's imagine a molecule vibrating (due to heat) in a dense sea of air molecules. When it vibrates, the surrounding molecules will follow up and down due to electromagnetism, like making a wave from lifting a heavy rope up and down. This wave it creates is called an electromagnetic wave, specifically with the infrared wavelength. In fact, if the particle is hot enough the EM wave may be of a visible light wavelength due to a phenomenon called blackbody radiation (but now I'm getting side tracked). When the heat of the particle emits an EM wave, an infrared camera can detect it using a thermocouple. A thermocouple is an electrical device who's power changes depending on its heat. This is how we can record the heat, but then also transmit it to a screen who's pixel color is adjusted based on the power of the thermocouple (which is given by the heat of the object the infrared camera is sensing).
Why do infrared flashlights emit red light that is visible to the human eye? Isn't infrared radiation invisible to the human eye? I'm asking this because I've seen this red light many times, on security cameras with infrared illumination.
Great question. We first have to define the infrared with respect to wavelength. Most surveillance cameras use visible light cameras with CMOS detectors. If you remove the (near) infrared filter from these cameras, they can still detection near infrared light. Usually in the 750 to 850nm regions from IR LED illuminators. This is often marketed as "nigh vision". near IR LEDs also typically still emit light that is somewhat visible to the human eye. It bleeds down below the 700nm wavelength, which appears as a deep red to the human eye. However, most of the light that the LEDs output is above that region. That's why you can still "see" some of the light with your eyes.
that’s because air is made of fast moving gases. they dilute each other to make a homogeneous (evenly distributed) mixture, so the temperatures of air will remain relatively uniform all throughout. the infrared camera would detect differences in temperature, so if you had concentrated hot gas contained near colder gas then it would likely be shown on the camera. think: hot exhaust exiting a car
@movitherm Is this the physics explanation? I don't think any of 'franks' answer is true. Sounds like a childs guest. The camera will not measure air at any temperature, nor liquid nitrogen (which is 78 % of the air) Why not?
@@fractalnomics yes, that’s the physics answer. liquids and gases have higher entropy than solids, which favors mixing- heat will be transferred from gases and liquids faster than from a solid (the main reason temp irregularities are easier to see on solids). The temperature IS detected from gases and liquids, but think of it as the background. If for example the temp of the liquid reads green on the infrared camera, then all you’ll see is green (as the heat is spread evenly throughout) and you may go “Hey, it’s all one color. Why is it not detecting temperature!” but it is, and you just can’t see many irregularities.
How come these cameras measure the temperature of the "things" that are far away and not for example the temperate of the air in between?
Hi R2D2 - great question! Air is essentially a mixture of gases. Most gases are transparent to infrared cameras and the camera sees right through them. Infrared cameras typically only see infrared radiation from a sold surface. There are exceptions to that though. For example, for a significant distance, water vapors will attenuate the infrared radiation.
@@movitherm Interesting! Thank you for the answer
@@R2D2SD You're welcome!
@@movitherm hi sir
@@movitherm Question, what would happen if an object was covered by a material that made it invisible? like the new technology developed by several militaries
I don’t believe this fully answered the question. what is an infrared camera made of? how does each element detect heat? how can the heat be recorded and digitized?
There are different infrared camera detector technologies available. Each one works a bit different. We essentially differentiate two main categories, micro-bolometer type detectors and quantum well based detectors. The micro-bolometer type has tiny thermocouple elements as pixels that change resistance based on the infrared radiation it is exposed to. The quantum well type actually measures photons in the infrared wavebands. Either the change in resistance or the amount of photons captures is then digitized into a digital count. Some magic sauce is used to convert infrared radiation into temperature and on the software side you can now measure temperature.
@@movitherm bruh put this in the video with visuals so everyone can understand. Why give visuals for the simple part then boring paragraphs for the RELEVANT but complicated and boring part😑
Search "How do Camcorders work?" I have read the creator's reply and it seems to be that.
I am a student and i am learning, if i made a mistake, kindly inform me and explain it to me.
You have said that the detector sees the infrared radiation. But where does this comes from? Does the bike(or any object) emits the infrared radiation or we from the camera incident any light or etc., to reflect it back and measure with it?
The infrared radiation comes from the heat of the particles. Let's imagine a molecule vibrating (due to heat) in a dense sea of air molecules. When it vibrates, the surrounding molecules will follow up and down due to electromagnetism, like making a wave from lifting a heavy rope up and down. This wave it creates is called an electromagnetic wave, specifically with the infrared wavelength. In fact, if the particle is hot enough the EM wave may be of a visible light wavelength due to a phenomenon called blackbody radiation (but now I'm getting side tracked). When the heat of the particle emits an EM wave, an infrared camera can detect it using a thermocouple. A thermocouple is an electrical device who's power changes depending on its heat. This is how we can record the heat, but then also transmit it to a screen who's pixel color is adjusted based on the power of the thermocouple (which is given by the heat of the object the infrared camera is sensing).
Why do infrared flashlights emit red light that is visible to the human eye? Isn't infrared radiation invisible to the human eye? I'm asking this because I've seen this red light many times, on security cameras with infrared illumination.
Great question. We first have to define the infrared with respect to wavelength. Most surveillance cameras use visible light cameras with CMOS detectors. If you remove the (near) infrared filter from these cameras, they can still detection near infrared light. Usually in the 750 to 850nm regions from IR LED illuminators. This is often marketed as "nigh vision". near IR LEDs also typically still emit light that is somewhat visible to the human eye. It bleeds down below the 700nm wavelength, which appears as a deep red to the human eye. However, most of the light that the LEDs output is above that region. That's why you can still "see" some of the light with your eyes.
But they don't detect air; strange.
that’s because air is made of fast moving gases. they dilute each other to make a homogeneous (evenly distributed) mixture, so the temperatures of air will remain relatively uniform all throughout. the infrared camera would detect differences in temperature, so if you had concentrated hot gas contained near colder gas then it would likely be shown on the camera. think: hot exhaust exiting a car
What @@franklinmontez8733 said! Thanks for the answer!
@movitherm Is this the physics explanation? I don't think any of 'franks' answer is true. Sounds like a childs guest. The camera will not measure air at any temperature, nor liquid nitrogen (which is 78 % of the air) Why not?
@@fractalnomics yes, that’s the physics answer. liquids and gases have higher entropy than solids, which favors mixing- heat will be transferred from gases and liquids faster than from a solid (the main reason temp irregularities are easier to see on solids). The temperature IS detected from gases and liquids, but think of it as the background. If for example the temp of the liquid reads green on the infrared camera, then all you’ll see is green (as the heat is spread evenly throughout) and you may go “Hey, it’s all one color. Why is it not detecting temperature!” but it is, and you just can’t see many irregularities.
@fractalnomics where did you go home boy? where is the next brain buster question?