Ir Definition and 229 Threads

hello can someone tell me are ambient IR and IR in candle fire has different wave lengths? I'm trying to make a flame detector,so if there is different wave lengths i can use a filter circuit to filter only fire's IR signal. Thanks

Homework Statement I have attached the IR and NMR spectrum from lab. I have determined that there was a nitrogen present in the compound. There was no sulfur or halogens. The molecular weight was 138. The compound was solid and yellow color. It had a melting point between 124 and 134 C...

Help on IR light please! I want to know the Power that comes out of an IR Illuminator. The manufacturer only gives that power is 12mW at 85m. It also gives a beam angle of 35 degrees. A. I took the surface area of the sphere generated by the illumination. That is 4*pi*(r^2) B. The...

Hello, I am trying to understand the difference between Active IR and Passive Thermal Imaging. First, I'll start off with what I DO understand, and finish with what's confusing me: I understand that in Active IR, objects are illuminated with Near IR (NIR) light (695-1000 nm) and then...

Hello everyone, I want to focus IR on a small rectangular area using a Fresnel lens. I tried trial and error to find the focal point of the lens but can't seem to be able to get the exact point. The frensnel lens is a multiple fresnel lens. Can anyone please help? Thanks =)

Atmospheric gases play a role in planetary temperature regulation Carbon dioxide levels have been rising rapidly in the Earth’s atmosphere and are linked by the IPCC to “global” warming. Recent failure of measured temperatures to advance with increasing carbon dioxide has called this assertion...

General query about heat absorption. We all know that something that is black both absorbs and radiates heat better. My question is how does this property vary across the spectrum, if at all, for different materials (if there is any difference?). For instance, a black painted car will heat...

Hey, I found this forum on good, so I apoligize for my lack of knowledge, but I am trying to determine the IR frequency of these two IR Text Messengers. Theyre designed to only send messages to one another, so is there any way I could test to discover their frequency? Would it be written...

Ultraviolet light can kill skin cells but infrared light only warms skin cells even though both types of lights are from the sun. Why is this, explain using the photon theory...?

well i m designing a simple circuit in which a bulb is turned on and off by a simple household remote control. Normal remote control gives IR of 38 khz so i m using TSOP 1738, there is also an alternative of HRM 3800. Well i m having a problem that neither of them r working. When i press the...

no matter what theory we use , are all UV and IR divergences of the form ?? \int_{0}^{\infty} dk. k^{m} where 'm' is an integer or there are another divergent integral different from a power-law or logarithmic divergence ?? , and another question , can be this true i^{m+n}D^{m}\delta...

I've been looking all over the Internet for what I thought would be an easy thing to find instructions on. Unfortunatley, anything that comes close either complicates the matter with extra features or assumes I know a lot more about electronics than I do... I need to build a very simple...

I've seen the designs using the 555 timer as the base and making a 2 led IR emitter. These examples use 5v and only two leds to send the 40k signal. http://www.reconnsworld.com/ir_ultrasonic_555timer40khzir.html I would like to modify this design to run off 12v and use 8 infrared leds. I...

Is it possible to build an IR amplifier? I have a weak remote aimed a TV really far away. Is it possible to build a device that I aim the remote at, and it amplifies the signal, then sends a copy of the amplified signal to the TV? Pretty much a repeater? If so, how? Thanks

I recently bought a phototransistor emitter and detector from radio shack: http://www.radioshack.com/sm-matched-infrared-emitter-and-phototransistor-detector--pi-2049723.html . It didn't come with much instruction but i thought i could simply put a voltage across the emitter and the detector...

[SOLVED] Sites with IR, 1H NMR, 13C NMR, and mass spectroscopy? I was wondering if anyone knew where I can look at IR, 1H NMR, 13C NMR, and mass spectroscopy (sites or programs). I'd like to be able to input the name of an organic compound and be able to see these spectra. Thanks.

Homework Statement For (NO)2+, experiments show 1 Raman active vibrational mode around 1450/cm; 2 strong IR active modes at 2400/cm and 550/cm; and 1 weak IR active mode around 3600/cm. What does that say about its geometry? The Attempt at a Solution Never mind, I think I got it :)

I learned https://www.physicsforums.com/showthread.php?p=1098513&posted=1#post1098513" that some people are sensitive to lower frequency light than others. In fact, some people can see well into the infrared range. I was very skeptical, so I tested it out. I was right, I cannot see IR...

Hi, Quick spectroscopy question: Say I am looking at the sun with a near IR /IR spectrometer? I know there is H2 and He in the sun, and I assume I will see their spectral lines? If true, how come I see that, and the signal is not drowned by the heat from the sun? (since it is so hot, using...

I have tree files of IR spectra but I cann't open them, because I have no suitable software. I need to open them. does somebody knows some kind of freeware which I can use to open this files. or if somebody can I will send this files to open and copy them into MS Word and send them back to me...

How does the "clock" know when to slow down? Screwy question, I know, but the following thought experiment might help to make clear what I'm asking. You and a clock are in a box. You can't see outside the box. You have no external references. Inside the box you appear to be in free...

Right now we have a projector and it is about 75 feet away. The remote, well, works pretty terribly to say the least. What I would like to do is build an IR amplifier to boost the signal so that the projector can pick it up much easier. What I plan to do is use some sort of buffer/driver IC...

I need help identifying this compound. I already know at 3000cm-1 and less than 3500cm-1 its a C -H. Less then 3000cm-1 must be of C-H alkane. Thats pretty much all I have identify. What I really need help is identifying the rest andnaming the compound. Any help would be appericated.

i'm having fierce trouble trying to obtain information as to the peaks/bonds in the IR spectra of the following; benzaldehyde, cinnamaldehyde, benzophenone, cyclohexanone and acetophenone. i keep typing in plenty of the keywords in the various search engines but to no avail. all i need is...

I am trying to figure out the best way to build an IR remote control. I was going to use momentary switches on the remote and need 18 switches. The remote is going to eventually control a preamplifier I am building for a senior design project which is still a few semsters away. I figure it is...

I've been looking all over the Internet for what I thought would be an easy thing to find instructions on. Unfortunatley, anything that comes close either complicates the matter with extra features or assumes I know a lot more about electronics than I do... I need to build a very simple...

I'm trying to design a simple circuit that will enable a magnet passing by an induction coil to send an IR pulse to a simple receiver plugged into a Linux box. This will be used to measure the speed of a turning wheel without having to worry about batteries or a power block of any sort. Any...

how do u increase the sensitivity of an IR sensor? what are the options?

Hello, I recently got some IR transmitter LED's and reciever LED with the ide of using them to make somewhat cheap remote control. whern I started to build it, I realized that I didnt know much about what was going on and how I should put it together, so I experimented with it a lot to figure...