Infrared Definition and 226 Threads

Hi All, I am after an equation/table of that describes the Transmissivity of Air in the 7.5-13.5um region. I understand that Beer–Lambert's law says that the relative intensities of a beam in a medium varies exponentially with distance and particle density, but you need to know the...

I want to use the ray tracing software ZEMAX to calculate reflection and absorption using thin metal oxide coatings on for example plastic materials. For this I need is the real and imaginary part of the refractive index in the wavelength region 1-10 micrometer for the metal oxides ZnO, ITO...

Hello. We've been entrusted the job of building a dryer for firecrackers. We were approached by a huge firecracker manufacturing firm here for the job. The current MO of drying is simply laying the product out in the sun and allow evaporation of moisture. But now they plan to go in for a...

Hi everyone, I'm looking to create a circuit where an infrared detector is located above the edge of a small wooden disk with an infrared light also on its edge. I want to wire this up so that while the detector does not see the light, power is supplied to a motor that will turn the small...

Hello I asked a question about infrared and UV a while back for which I got some very informative responses: https://www.physicsforums.com/showthread.php?t=676881 This is in a sense a very short follow up question: Is the reason that we don't feel 'heat' from an infrared remote...

Astronomy homework question -- stars emitting in infrared Dear All, Hello! This is my first post. I am taking a distribution introductory astronomy course (low on math) and am having trouble with this question: Which object emits more intense infrared radiation: _ the Earth _ the Sun...

I am designing a tyre temp monitoring system for my Final year project and I would like to know if it is possible to somehow modify a infrared phototransistor to be able to measure an objects temperature in a range of -20 - 120 C. Any suggestions would be greatly appreciated.

Hi there, I have built an InfraRed beacon using a 555 timer using a 10K pot to tune the circuit. How can I test that it is pulsing at the required 38kHz frequency that I need. I have tried using an oscilloscope, by connecting up the Earth and probing one of the legs of the IR LED, but I...

I wonder if some old stars will become invisible to our eyes after a while because of the redshift? Since they get further away from earth, maybe we won't receive their radiation in visible light any more? I'm talking about stars that are not obscured by any other objects or dust, which you...

Hi everyone! I am looking for a solution to heat up photo chemicals (I'm doing darkroom printing in a cold garage). I need the chemicals to remain at a fairly steady 20 degrees C, whilst the air temperature is significantly lower (e.g. 7 degrees). My question is whether or not an infrared...

Say you have a light source that produces light in the 700-1000 nm spectrum (Infrared), you use it in a dark room, and record with an infrared camera sensitive to the same spectrum. The visible light spectrum is 400 nm (violet) - 700 nm (red). Therefore if you translate the recording into 700...

This is a talk by Nima Arkani Hamed of IAS at Princeton from a few days ago, where he discusses his thoughts on the dark energy problems of cosmology and various popular research programs aimed at addressing it by modifying General relativity at large distances (examples like DGP, Galileons...

What happens if an infrared remote control is pointing and coming at your eye really fast while transmitting... would the frequency of the em waves increase? If so, how fast would it need to be traveling in order to appear red?

Hi! In e+/e- to mu+/mu- scattering, if the initial electron/positron radiates a photon, then I have an IR divergence. How do I treat it?

Gas Grill -- Conventional or Infrared? So I know we have some serious grillmeisters here, who can help me with this. I'm in need of a new grill and I see that there are both the normal and now infrared grills. Does anyone have any experience with the infrared? They are pricier, but they...

From what i understand thermal cameras like flir can see "heat" because objects at room temperature release Ir light like hot metal would visible light. But most cameras like commercial security cameras can see IR but don't work like thermal cameras because they aren't sensitive to the right...

Infrared works perfectly fine as a watermark on still images (infrared LEDs put at the back of the image) and even videos when the surrounding is dark. Is there a way to make it more noticeable even in broad daylight? And let's say, if my surrounding is dimmer and I want to obscure...

An infrared gas analyzer gives you the concentration of a given molecule that absorbs radiation in a specific infrared band, in a gas, by determining the attenuation of radiation of the frequency in case, when in a path between emitter and receiver is a sample of the gas in analysis. My question...

Hi, I constructed a device that consists of two metal pads atop a semiconductor material. I'm still confused on the whole Ohms law thing. Infrared radiation strikes the metal, and we're testing it at different temperatures, but I don't know what happens from there. My questions are: 1. Is the...

is it true to say that any molecule having a centre of symmetry will have the symmetric stretching IR inactive? thanks!

Microwaves heating is often referred to as dielectric heating, but I'm not sure why this seems so special to specify of all the different thermal radiation frequencies. Doesn't infrared heat the dielectric material as well in a similar process? Isn't radiation heat transfer common for a wide...

Can a lux meter measure infrared intensity like it does for the visible light? I read from somewhere that it cannot. If you have an IR illuminator on in the dark and hold up your 'regular' lux meter to it, it will likely register 0 - an unhelpful and misleading result. I'm just wondering if...

Hello, why do every atom with a temperature different from the absolute 0 emittes infrared radiation? Where does it came from? Thank you!

Infrared heats a body but UV heats less! If we consider two bodies of indentical properties (and temperature) and we apply radiation on them with different EM wave ,One with Infrared and the other with UV ray,we find that the body exposed by IR has more temperature increase with respect to...

So, as the title describes, I am trying to build an infrared heating element for my own heating panel. I want to use this heater to cure an epoxy at 350F that is about 5" away. I'm an EE so the wiring and such will be simple but the heating calculations are beyond my area of expertise. Here is...

First of all, besides the question in the title (which is an open ended question) can someone please tell me whether it is possible to "record" all infrared signals? If it's impossible, is it impossible in the way that virtually every remote for certain appliance has its own unique frequency...

Hi, I'm a computer scientist w/ very little hardware experience. I've been playing with the idea of using NIRS for a brain computer interface. The basic principle is pretty simple: You have a laser diode and a detector that is 2-3 cm away from the diode. Unfortunately I have almost no...

Hi all, got a bit of an experimental/theoretical confusion here. A group of us are doing an investigation into limiting the heating of solar panels while still allowing the majority of visible light to reach the panel cells. One theory we're intending to test out is using prisms to change...

Do different materials (i.e. granite, steel, water, etc.), all at the same temperature, emit the same infrared wavelength?

I have learned that penetration ability increases with frequency. But why can microwave cook faster than infrared wave? Infrared gas a greater frequency so it should penetrate more and thus cook faster. So I'm not so clear about this. Thanks for the help

The other night I was watching a campfire and the infrared light from it was intense enough that it warmed my face quite a bit, almost uncomfortably. I must have been receiving quite a bit of invisible light in my eyes, but there was no damage (and I've never heard any warning about watching...

Problem: I'm trying to optimize an inexpensive digital camera with a CCD sensor for NIR video. As of right now (after removing the IR filter) it doesn't work well in the dark at all (even with a basic visible light filter ... obviously). I have to direct at least a little bit of regular light...

Infrared contribution of vertex correction gives an infinity, the resolution is to add infrared bremsstrahlung contributions as well, I can follow the math, but I'm not so convinced by the justification of this resolution given by Peskin(and Weinberg, and whatever I can find on internet)...

Hi all, is there an efficient way of splitting both of these waves of sunlight?? I've came across http://coolcosmos.ipac.caltech.edu/cosmic_classroom/classroom_activities/herschel_example.html and thought of an idea of using a prism. But, do you think that is is efficient? ( I'm going to use...

What are some of the windows or materials that are used to only absorb the infrared spectrum of light passing through the material?

Hello everyone, I have a project in science and I am puzzled with something. I want to have and IR emitter and an IR detector to act as a burglar alarm that will activate lights and a speaker-like thing. The only problem is that the IR set that I am using opens the circuit until it gets...

Hello! I'm writing a thesis about the optical properties of CO2. However I'm having a hard time finding any solid material about the basic info of the absorption spectrum of CO2. I'm especially interested in the absorption band at approximately 4,3µm. If any of you guys know some good articles...

I thought IR light has the least energy since UV light has the most (shorter wavelengths more energy). The article states that the IR light makes the air temperature at the highest, what is happening here?

i want to know about wave length of infarade wave and working range

Is it possible to filter out infrared light using a prism, and if so, how? What is the math involved to do this? I want to come up with some effective, durable ways to filter out IR light for solar panels, to keep their temperature lower to make them more efficient.

Does anyone know which, if any, liquids or chemicals absorb infrared light but not visible light? In other words, something that looks clear but appears dark or black when viewed in infrared. Help is greatly appreciated!

Please teach me this: It seem that the ultraviolet divergence has origin of we unknow the physics at very small distance(very large momentum,then very small distance).So we must cut off the very large momentum by renormalization procedure.But I do not understand the origin of infrared...

Hello, I have purchased a Casio CMD-40B watch. It functions as a remote control for your TV and Cable boxes. How it works is, you look up the specific TV's "code", tell it to the watch, and your watch now acts as the TV's remote control. Here is the Watch Manual...

And still be re-emitted at the same wavelength, even after being absorbed? I imagine visible colors, to hit a dark colored surface and become absorbed. In that process some of the object's electrons (I believe the outer shell) become energetic or is raised higher. To achieve equilibrium, it...

Homework Statement A plane harmonic infrared wave traveling through a transparent medium is given by Ex(y,t) = Eosin2(pi)[y/5*10-7 - 3*10-14t] where all the quantities are expressed in S.I. units. The vacuum wavelength of this wave is? The Attempt at a Solution I got the answer as 1000...

I'm confused about infrared spectroscopy. Wikipedia states that "when the frequency of the IR is the same as the vibrational frequency of a bond, absorption occurs." However, if I look at some vibrational transitions of HCl for the anharmonic oscillator, I see: 0-->1 \omega = 2885.7...

Hi .. May i ask why does a infrared photograph of a person look different from a photograph taken from visible light ? Relevant Equations : V = ƒ x lambda I believe it has got to do with the wavelength or frequency. However, i can't explain it ..

I read about a type of identification system in which a person's hand is stamped with some sort of ink or substance that is invisible to the naked eye. This normally invisible stamp on the human hand is visible under an infrared light. I remember that an infrared camera sees things that give...

hi,, i m building this IR receiver circuit, to work as a switch for electrical appliances such as a lamp,, so when i send an IR beam to the circuit, the lamp should turn ON and stay ON even the beam is no longer present, but it should turn OFF when i send IR beam again. Which relay...

Or can we feel heat in the form of visible light, not just infrared waves? Because I know heat is really kinetic energy (temperature), but why is it that we can't feel heat in the form of Radio waves or Micro waves, but then again Microwaves are used to heat food how? Main question hear is why...