What's the IR resolution on the Star Safire 380 on our UAV's? These are on Anka's or on our Bayraktar's? Or both?
I found the following info on safire 380:
https://www.flir.com/globalassets/imported-assets/document/flir-star-safire-380-hd-datasheet-ltr.pdf
It says that it comes standard with 640 x 512 InSb MWIR FPA
And 1280 x 720 InSb MWAR FPA being optional.
I don't really know what InSb and FPA means and I don't know which of these options is currently equipped on our UAV's. Is MWIR it the same as IR you guys are talking about? Or is MWIR something completely different?
FPA: Focal Plane Array. This means you use planer sensor which is consisted of an 2D array of sensors. This is a general term for every kind of digital imaging systems including ordinary digital cameras etc.
InSB: In: indium Sb: Antimony Those are the elements used to make that FPA detector chip. Indicates that the materials used in chip. Think it like GaN or silicone chips.
All those above are about sensor tech.
MWIR: Middle Wave Infrared
For MWIR/LWIR or just IR I shall tell you that light has a spectrum. X-Rays, visible light, gama rays, IR, microwave and every kind of light is basicly same. Just the energy of photons(and their frequency&wavelength as a result) changes. That is a crude shema of spectrum:
At this graph left side is higher energetic and right side is less energetic photons. (this is why x rays and gamma rays gives you cancer) As you can see visible part(our eyes can see) is a small part of the spectrum.
When energy increase frequency increases and wavelenght gets lower. When you go to right part; energy decreases and frequency gets lower wavelenght gets higher.
I told that so I can tell you different parts of IR.
Look at infrared part. It is right next to visible light. It is lower energy than visible light. This is important.
Some people divide IR into different parts but
generally there is no scientific purpose for that. It is for technical purposes. Some people divide it into 3, some into 5 and this division into parts changes from one dicipline to another. (for example astronomers divide it into 3 but they use different sized parts than something called cie shema)
MWIR is used in 5 parted general purpose specrum. Those are:
NIR (near infrared, near to visible light)
SWIR (Short wave infrared)
MWIR (middle wave infrared)
LWIR (long wave infrared)
FIR (Far infrared : nearly microwave)
NIR is the most energetic one. (At the left side of IR graph; remember the graph at top I have shared)
FIR is the least energetic one.
Why those are used?
Every material in universe which has higher temperature than absolute zero(0 K ~ -273 C degrees) emits its thermal energy as light. That applies to EVERYTHING! When it is really cold(near absolute zero) it emits that energy with microwaves. When you heat it it starts to glow at FIR. When you increase its heat it more then starts to glow in LWIR, than MWIR, then SWIR and NIR. For example; when you get near to a ratiator you feel its heat at your face. This is the light you can not see. It emits IR radiation and your face absorbs that light; so your face gets hotter.
When you heat more that material starts to glow in more energetic light; visible spectrum. This is why a really hot knife put into fire glows in a way that you can see it glow.
That applies to you too. Your body surface temperature and surface of your clothes/shoes/hat etc. are at a certain temprature range. (for example lets say 20-40 degrees) So they emit IR radiation in certain range of IR.
As you can imagine those MWIR etc. corresponds to different temperatures. MWIR corresponds to 3-8 microns wavelenght and that corresponds to peak thermal radiation of 89 - 693 C degrees. (though it can detect more. this is just the peak of radiation) For LWIR that is -80 - +80 C degrees.
So; MWIR / LWIR / FIR / NIR etc is for different thermal ranges. If you use NIR that is for thousands of degrees.(generally not used for imaging) IF you use FIR that is generally for really cold astronomical objects far away from us. MWIR and LWIR is generally used in thermal imaging systems because those corresponds to light emitted to general purpose targets in ordinary life. (for both detecting people and fighter jets; those 2 IR spectrums can detect nearly everything you need to detect)
