Lately I have been messing around with my Video Cam. The "Night Shot" is of poor quality on it, so I began to make my own IR by using multiple L.E.D. Lights. This works great, but ONLY for "shorter distances." I than began using using "Reflectors" from various flashlights as a way to "beam out & focus" the "light" at greater distances. This works great, but only to a certain distance. Bottom line is, having 25+ L.E.D.'s W/ fixed reflectors mounted off my small handheld video cam just wasn't practical.
Anyways, I was than introduced into "Thermal Vision" (the other type of night vision). I just took the IR screen attached to my CCD behind my Cam Lense off and replaced it with a Negative screen and BAM Thermal Vision!
Let's get to the point, I want to apply "Night Vision" to my rifle scope. I COULD use IR & the "L.E.D. Method" but the problem is Infrared filters just make it so you can see low levels of near infrared present whens theres a natural source (like moonlight OR starlight) It does NOT amplify them.
The only way to detect invisible frequencies is to use a senor such as a camera to detect, amplify & re-project those images into your eyes.
And, remember this is going to be applied to a rifle scope so "amplification" is vital. My rifle is set for 250 YRDS, so I need it to poke out there quite a ways.
So the question how to amplify?
Let's re-cap on IR screens. I just want to make sure I have this down. An IR screen is basically a series of colored screens to block what ______________________? Is it portion of the spectrum? I know with IR, it works by collecting tiny amounts of light, including the lower portion of the spectrum. Basically its just blue and red film screens stacked atop eachother right? What do they "block out?"
Anyways, On to another thing. Cross Airs/Reticals?! MOST scopes do not come with illuminated cross airs so in theory, I would think that it'd be difficult to see the cross airs evan when using "Night Vision." I take it this has a lot to do with whether or not you mount the Night Vision before OR after your scope?
What I have seen in the passed is people actually DITCHING their Cross Airs/Reticals and heading with an Infrared Laser. Now, there is no scope in play here. Its basically just a screen/monitor/lense that allows you to view "infrared." In this case, the Infrared Laser. In this case, the laser actually becomes your "cross airs/reticals" and that is how you aim. Cool thing about this is that ONLY YOU can see the Laser since it's Infrared, but you have to view it through some sort of screen/monitor.
...Now sighting one of these things in would be interesting lol. You would have to do it in the dark!
Another thing I have seen with the Screen/Monitor is a Range Finder. Most Range Finders use a "Laser" set up in a triangular configuration to figure out distance. There is a mathematical equation to figure this. Wouldn't it be Bada** to set this up on a rifle and have the distance project into your screen/lense/monitor!!!!!!!!!!!!!!! Hell yeah it would!
Your laser would be would extend out from your monitor and onto your target than reflect back to another type of Cam located above your monitor and than a signal would be sent to your monitor to calculate distance. I assume this would be a digital read. I have seen many DIY LCD screens and I don't think It'd be too hard to mount a small Chip in the stock of your rifle to figure compute distance
Anyone know how to achieve this? It would be nice to ditch using natural light (starlight/moonlight) and head with a "newer generation"
well, a camera sensor is sensitive between something around just below 400nm up to about 1000nm. The visible range is usually said to be somewhere between 400nm and 700-750nm, so your camera can see more than your eyes. this 700-1000nm range is the near infrared (NIR) range that your camera could detect
aditionally, each pixel has a certain color filter (blue, green or red), but usually, these filters all still transmit the NIR. In combination with the IR filter, all pixels will just detect the color, without the NIR and you get a nice color image.
removing the IR filter, will allow you to record the NIR region, so as long as there is (almost) no visible light (like when it is dark), you'll be recording the NIR. Note that this is NOT thermal vision, which is using longer wavelengts (µm wavelengths)!
I don't think this is the same as what you were discribing.
as for seeing an infrared laser on a screen, use a laser with a wavelength between 700 and 1000nm. Typical available wavelengths are 780nm and 850nm, but there are others as well. Please note that there are safety concerns when using non-visible lasers. I suggest reading CDRH chapter 1040 for more information!
Now, this distance thing could be a challenge. The easiest way of doing this would be to use one of these tools for measuring distances between walls. These are reasonably cheap and work quite well, but I don't know what the maximum range that can be measured is.
These tools use a red laser, so you'll need to find a compatible NIR laser diode to replace the red laser.
Making such a system from scratch is not an easy task because it requires knowledge of mixing electronic signals, pulsed lasers, phase-shifting, etc. There are also a few ways to measure distance with a laser, each has its own advantages and disadvantages and making it work for the desired distances will need some understanding of the mathematics behind it. I'm no expert at this so I'm afraid I can only give you a rough idea of the problem to solve.
to reach out to 250y with night vision, you're going to need an ir laser. led just won't cut it.
i'd recommend trying a watec 902 camera, very good NIR sensitivity. you don't need color at night, so go b/w with a 1/2" sensor if possible.
you'll not require an illuminated crosshair.
Last edited by nobbybonez; 03-23-2012 at 03:39 PM.