Infrared Definition and 226 Threads

I have a work assignment where I'm supposed to calculate the transmittance of blackbody radiation through liquid n-heptane, and I have data of the heptane's absorption coefficient on the wavelength interval from 2.6 to 15 micrometers (it has significant peaks at about 3.5 ##\mu##m, 7.0 ##\mu##m...

So, as far as I understand IR thermometer works by measuring light irradiance coming from an object (in the IR spectrum) and then calculating the object temperature using Stefan's law. Since the irradiance falls like 1/r2 with distance, I am wondering how it takes distance into consideration...

What do you think of the following paper about QED? https://journals.aps.org/prd/pdf/10.1103/PhysRevD.96.085002 Infrared divergences in QED revisited Daniel Kapec, Malcolm Perry, Ana-Maria Raclariu, and Andrew Strominger Phys. Rev. D 96, 085002 (2017) – Published 10 October 2017 It has been...

I've been recently studying the correlated-k method of calculating the absorption of EM radiation when passing through a sample of given thickness. I'm not sure if anyone here has experience on the same subject, but in case there is I have some questions... Suppose I have a material sample that...

I had an experiment involving FTIR (incoherent light source) to measure the thickness of plastic film through making use of interference fringes. I don't understand how the interference fringes can occur over a frequency range (in term of wave number ν for FTIR) and also how it can occur at the...

I do attach a plot (pdf and Matlab) of a recorded spectrum where I do not manage to find the gas specie overlapping CO2 Could you help me? Best Alain

Hello all, I was driving down the road yesterday, and I realized that I don't really have a solid grasp on how frictional forces cause infrared radiation. Can anyone explain, or direct me to a resource that explains, how this happens at the atomic level? I am thinking that the work done...

I am looking for bulbs that would be emitting a spectrum characterized by a color temperature of between 500K and 1000K or any kind of light fixture that only emits long IR wavelengths. Does such a thing exist?

Sooooo... I have a Far infrared (FIR) sauna. It has large flat 'carbon' panel heaters. They get warm to the touch and won't burn you if you touch them. My non contact infrared thermometer zapper says that they get to about 70 degrees C. They are meant to be producing lots of FIR. A regular...

Hi, I made the following circuit for 38kHz infrared receiver TSOP38238 to increase the detection range above 10 meters. i was quite happy to see the range is more than 20 meters with TSAL 6100 LED. but i am facing a problem, my circuit works like a relay circuit. i have to wave my hand in...

Hi All, It is known that ordinary cameras can make infrared radiation which comes from remote controls visible at their own display. My question is about the explanation of this fact. Is the electronic process simple to describe? It seems that the infrared can produce photocurrents which are...

I need some industrial applications where IR is used for communication. Also I need to know whether can I use it to transmit my measured data of torque and temperature (measured using RTD and strain gauge) from a Rotating shaft running at 7500 rpm through IR communication ?

Question, exactly what frequencies in the infrared spectrum can partialy penertarate our atmosphere and under what circumstances

Hello Forum, Thermal energy (heat) is associated to the infrared portion of the electromagnetic spectrum. Why? I know the human body emits radiation in the infrared (10 micron). Heat is associated to warming. Are infrared wavelength the resonant wavelengths at which molecules in most objects...

Hi there, We can't use Infrared rays outside for data communication of our home as sun light also contain infrared rays which possible will interfere with it.That's what i read in Data communication book. My Question is , Does sun rays also contain radio wave, microwave ? if yes, then why can't...

Hello, I am part of a synthetic biology team whose goal is to modify immune cells to respond to an incident wavelength of 670-702nm and emit a near-infrared wavelength of 650-900nm(to be determined). My goal is to create a sensor that will be able to detect this emitted wavelength through...

Hello, I'm looking for a gas (hopefully one that is readily available) that will absorb Nd:YAG laser radiation at 1064 nm. The purpose is to heat the gas to transmit heat into a glass fiber composite which normally does not absorb IR light.

Homework Statement "Infrared light doesn't travel through air easily". Why is that? Is it because there are lots of molecules that absorb the energy so that a reaction occurs? Homework EquationsThe Attempt at a Solution

I've read that H2O has an absorption/emission band around to 10 micron range. What conditions are required for photons of this wavelength to be emitted by H20 gas? In particular, how hot would the gas have to be? What amount of pressure is required? Under everyday conditions (like steam possible...

I'm trying to remember back to my undergrad physics days. Can anyone point me to a good textbook to compute the following? Given an infrared telescope with given specifications, such as the Infrared Astronomical Satellite and a star of defined intensity in the field of view at a specific point...

A low-e coating in double glazing should reflect long wavelength infrared rays (LWIR, 8-15 µm). However, glass absorbs LWIR. (For example, thermal imaging camera's cannot see through glass.) Are long wave infrared rays able to reach the low-e coating?

I was curious about what forces can be applied to a molecule to cause a rotational emission.

We have LED arrays for visible lighting. What problems exist for using infrared LED arrays as a heat source for humans, like those in a residential settings? Does effectiveness vary much by wavelength and skin color, clothing worn, etc? Thanks. :-)

Q. Regards infrared radiation, conduction and convection, is infrared radiation the starting point, the fundamental source of heat energy (thermal energy), and the fundamental source of the other two? I’m thinking that the Sun predates the Earth by 30 million or so years so the first heat...

I was reading about a process called up-conversion mentioned in Robert Boyd's Non-Linear Optics. It is essentially a special case of sum frequency generation (in sum frequency generation, two waves of different frequencies are sent into the crystal, and out comes a wave with a frequency equal to...

Dear Everyone, I'm searching for some specific elements for infrared (IR) sensor, such as Thermopile, Pyroelectric, Bolometer, MCT(HgCdTe), PbSe, or InSb sensors. Does anyone know how to get these kinds of elements ? ( I need some information about the manufacturers...) The elements are...

In the clear calm night,I'm out doing yoga exercises. My body will shine emiting infrared radiation as it stays blackbody radiation principal. So my particular question is , is it possible for some remote aliens on its remote planet to catch my infrared fringerprints of the image (with respect...

of microwaves?

I'm a bit stuck here guys. I am but a humble computer scientist, so I'm hoping you guys can give me some insight. I have an IR sensor that's capable of detecting a target temperature (whatever it's pointed at) and the ambient temperature. I have objects (humans, hot mugs, etc.) sitting in front...

We all know that angular molecules have 3N-6 vibrational degrees of freedom. So, why lots of books show that water has more than 3 modes of vibration, like rocking, wagging and twisting? Another example is -CH2 group. You can see what I said here: http://chemistry.ncssm.edu/watervibCS.pdf...

Is it possible to convert light in the visible spectrum to infrared or microwave light. What processes would be used to do this? Thanks, EJ

hi, so i want to be able to run a motor depending on whether or not an IR detector senses IR light. so the basic idea at the start was to connect the motor with the detector and a resistor in series and therefore if there is IR the current will flow turning on the motor. I then learned that the...

Hi I am currently trying to find the water absorption lines by using a Michelson interferometer, as a detector I am using an ocean spectrometer. The data obtained is thus the spectrum's "received" by the spectrometer. Am I right to assume that in order to find the absorption peak/peaks I should...

I am trying to estimate a current which I can get from the photodiode in a simple proximity sensor application having a IR LED emitter and a photo-diode detector. The LED and the photodiode are mounted in the same plane, on a PCB board, and separated about 10mm. If I have a flat Lambertian...

I have in my home an air conditioner and his remote controller that control by IR communication so when I touch one command in the remote controller the led of the remote controller become to flick in one frequency for example 100 flickers per second and this say for example to the air...

Hello, I have heard many times that red lighting is good for imaging applications where the effect of ambient light needs to be reduced to a minimum. What is the theory behind this? Why does red light (vs. other colors) reduce the effect of ambient light? Thank you.

Hi I was wondering if someone could tell me what kind of gases I could expect to see using an IR receiver between the wavelengths of 110 and 330 nm. As well as this id love to know what kind of glass could be used in order to not interfere with the actual results. Thanks a million

Hello All. I'm working on a project to build an infrared spotlight which will hopefully light up a distant object so that I can see it on an IP enabled night vision camera. The lens problem seems very straight forward, but I could use some help. Per the attached diagram, I want to focus the...

I'm curious about that do gases emit infrared radiation the same way as solid bodies do? If yes, how can it be detected like an infrared camera does?

Hello, I was wondering how one would be able to tell the difference between an object emitting a certain wavelength of the EM spectrum, vs. an object reflecting that same wavelength of the EM spectrum. For example: 1) Suppose I have an IR source at 7 microns. I point this source at water, and...

Homework Statement A python can detect thermal radiation with intensity greater than .60 W/m2. A typical human body has a surface area of 1.8 m2, a surface temperature of 30°C, and an emissivity e=0.97 at infrared wavelengths. What is the maximum distance from which a python can detect your...

I'm recently new to the field of 2D Fourier Transform Infrared Spectroscopy and am learning its applications. I would like to know its applications in biology. Specifically, is there anything in the 400 nm to 1000 nm range that is important in protein structure, protein dynamics or biology in...

I'm trying to understand the issue of CO2 and global warming better. Can anyone explain to me the mechanism by which CO2 in particular converts infrared radiation to heat. I've had a semester of college chem and three semesters of physics, but I'm not sure what theory I should be able to use...

1. Homework Statement Hi, I have to do lab experiment - estimating infrared wavelength (from remote control). My experimental setup includes CD, remote control, webcam (without IR filter, so I can see the infrared radiation), sheet of paper (I will see diffracted light spots on it) with hole...

I am thinking about a possible experiment, and would like to measure the temperature of gas in various places inside of a glass enclosure. Is it possible to use an infrared laser to this? Thanks

Is it possible to have a material that transmits infrared in one direction but not in the other? There are a few articles available that say it is, though I don't have any here with me now. So, let's say you make a hollow sphere of this material, oriented so that infrared light can pass out of...

Hello Forum, Why are infrared (thermal) cameras, those that produce interesting thermographs of objects, mapping their surface temperature, so expensive? IR sensors are ubiquitous and very inexpensive...What is the difference? thanks, fog37

If you have a momentum integral over the product of propagators of the form \frac{1}{k_o^2-E_k^2+i\epsilon} , why are there divergences associated with setting m=0? Factoring you get: \frac{1}{k_o^2-E_k^2+i\epsilon}=\frac{1}{(k_o-E_k+i\epsilon) (k_o+E_k-i\epsilon)} . This expression has...

Please tell me about common materials which absorb IR sunlight radiation in the band of spectrum 1.1-2,5 microns and which will not allow the penetration of IR if some surface is covered with thin layer of them ?

I'm working on research into the feasibility of separating out the infrared rays above 1200 nm in sunlight for solar power generation. Since silicon cells do not effectively harness these wavelengths, we are experimenting with using interference coatings and a wave guide to separate these waves...