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On our rocket payload, we have a sensor that is to measure UV radiation. However, it goes a little into the violet/purple range of the electromagnetic spectrum. Any idea of using a blue/purple filter that won't mess up the rest of the data?
yes
An actual scientist wouldn't ask such silly questions >=|
some of us are aerospace engineers and don't know jack about detecting UV light 
some of us are jack and know aerospace engineers from UV light 
you need to know what the output of the sensor is for a given wavelength of radiation. get the min/max range for uv radiation in this form, then tell the software handling the data to ignore anything outside this range.
woah.
![[TI] Lateralis](https://imperialconflict.com/forum/img/avatars/1280.gif)
A priori it is difficult to know if a 'blue/purple filter' will or won't affect the detector efficiency. You will have to run some tests yourself to determine exactly what frequencies of EM radiation get absorbed by the filter, and the efficiency of that filter.
If you *really* need to get rid of the blue/purple frequencies then you could probably use an filter which absorbs whichever frequencies you like. If it absorbs UV radiation then your signal-to-noise will go down but then you just count for longer to get better stats.
In any eventuality though if you use a filter you *must* know the attenuation coefficient as a function of frequency over the whole active frequency range. You'll need that to normalise the data.
Alternatively you could just find a material that only absorbs in the UV band. I would think there are some semiconductors that can do that. Aluminium nitride (AlN) I think absorbs preferentially in the UV band because of its 'electronic band structure', but you can check that with the published literature.
can I say blue/purple frequencies sounds a little gay?
Destroyyoutoo, Corpse, Walking, and Lateralis. On UV Radiation Absorption: The Exact Attenuation Coefficient of a Blue/Purple Filter. Imperial Conflict: Hello fellow scientists, 2011.
You're welcome.
The UV is into the cold part of the visual spectrum, and infra-red is into the heated portion of the spectrum. Why would you be puting a filter of cold light on a cold light radiation detector?
That's like puting a cap on the camera lense.
I got two pirate eye patches for you, and we'll just call you No Eyed Willie.
> Destroyyoutoo wrote:
> some of us are aerospace engineers and don't know jack about detecting UV light
*aerospace engineering students
And I don't think the science lot take kindly to the engineering lot referring to themselves as scientists ;P
wow pixies you seem very familiar
Just thought I'd drop my penis on the table. I may join up again in a couple of weeks, in time for the new MW round.
"And I don't think the science lot take kindly to the engineering lot referring to themselves as scientists ;P"
no kidding, I've asked him to help me experiment with a 2 stage rocket that's fired from an air cannon and can deliver a 5kg payload a kilometer away with an accuracy of 5 meters, and he's just not interested
also it should fit in the trunk of a car, dissassembled. And preferrably be manageable by one man in darkness.
Stop trying to get on a no-fly list!
Imperial Forum → General → Hello fellow scientists
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