I was wondering how to focus a or temp sensor. The sensors seem to be 90 degrees and 1 deg is preferable. I am trying to make a P&T temp sensor for cold things left out on kitchen counter.
mattlogue:
I was wondering how to focus a or temp sensor. The sensors seem to be 90 degrees and 1 deg is preferable. I am trying to make a P&T temp sensor for cold things left out on kitchen counter.
Your post makes no sense. You ask about focus for an IR light, the seem to ask about positioning. What is the real question?
Paul
Normally you focus the light source not the sensor however there are several possible solutions. You can put the sensor in a tube, this will greatly reduce the side radiation. Also you can purchase a narrow beam sensor, there are many on the market. IR does not focus the same as visable light but it is similar. I would suggest your get your trusty slide rule or calculator out and calculate the length of the tube you need to get the 1 degree acceptance angle you desire. This response is to help you get started in finding the problem, not solve it for you.
Good Luck & Have Fun!
Gil
mattlogue:
I was wondering how to focus a or temp sensor. The sensors seem to be 90 degrees and 1 deg is preferable. I am trying to make a P&T temp sensor for cold things left out on kitchen counter.
If you mean a far-IR radiant heat type sensor then special materials are needed to focus heat radiation, since most materials absorb it heavily, including glass.
Polythene is transparent (most plastics are not), germanium, silicon (not silicone), and a few ceramics too are used for lenses in the 4µm to 10µm wavelength range.
To get a beam-width of 1 degree requires precision far-infrared optics, that's probably going to be expensive,
$1000's expensive.
What is a P&T sensor?
PT sensor just pans n tilts... Like a turret. I just wanted want to emulate what I have in my handheld or gun, it my be 5 deg... That's fine... Polythene lens? What diopter for a 90 degrees sensor that are cheap on AliExpress?
Your post makes no sense.
mattlogue:
PT sensor just pans n tilts... Like a turret. I just wanted want to emulate what I have in my handheld or gun, it my be 5 deg... That's fine... Polythene lens? What diopter for a 90 degrees sensor that are cheap on AliExpress?
Perhaps you missed the classes on optics and the wave length of light the optics are designed for.
My trail camera takes perfect daylight pictures, but the IR pictures at night are all grainy and out of focus because the lenses are designed for visible light.
Paul
Sorry I'm depressed.
I know IR goes well thru germainium ... Brother had showed me it video tubes when I was a kid. Those were plates not lenses tho.
I may try tube idea, keep it simpler.
mattlogue:
Sorry I'm depressed.I know IR goes well thru germainium ... Brother had showed me it video tubes when I was a kid. Those were plates not lenses tho.
I may try tube idea, keep it simpler.
Put your IR sensor at the focus point of a "solar fire starter mirror".
Point it at your food, not the sun.
Paul_KD7HB:
My trail camera takes perfect daylight pictures, but the IR pictures at night are all grainy and out of focus because the lenses are designed for visible light.
AFAIK that's because in IR the focus is different. Old manual focus lenses had a mark where you have to move the focus (after taking it in visible light) if you where using infrared film.
My old DV camcorder works on IR (there was a lever to remove the IR filter in night vision) like many IPcameras that can put in and out IR filters.
I believe that in your trail camera the focus is set for visible light.
Edit: I mean near IR not thermal or far IR