DIY blinder

**TimeBandit** · 04-19-2010 10:41 PM

Having a little electronics background, I'm contemplating building my own IR accessory "headlight". There are no laws in FL (currently) regarding the utilisation of an IR light source.

The theory is simple: build a very bright IR light and place it right under my main headlight. Mount a switch near the handlebar to flick it on or off. Unlike the Blinder, this would not be a 'smart' system. I would have to keep it constantly on whenever I want to be protected. Next, it would not be smart enough to prevent jam codes. I believe the consumer products mimic the pulse-rate of the source as to stealthly confuse the Lidar gun. Mine would be more of a brute-force approach which means it would need to be ultra-bright. The concept is to over-exposed the LiDar's detection photo-transistor so that it can't see it's own reflection (hence overload light or popping a jam code).

I'm thinking along the lines of 12) Osrams - they operate in the 935nm range (peak) and consume 1 amp of power (that's very bright). LiDar operates at 904nm, but I'm sure it's IR photo-transistor is sensitive in a broader range. Plus the Osram is 935nm peak with +-50 nm wide. I also plan to supplement with 24) 200ma Opteks which run at 890nm +-25nm. Between the two it should be saturating the IR spectrum.

Any thoughts, ideas, tips on this?

**Google Adsense** · 04-19-2010 10:41 PM

**jimbonzzz** · 04-19-2010 11:40 PM

I can understand why you might think this approach might yield effective jamming protection. Unfortunately, it will not.

**thx1138** · 04-20-2010 12:43 AM

Read this
http://www.radardetector.net/forums/...ar-jammer.html

**TimeBandit** · 04-23-2010 10:38 PM

Thanks for pointing that thread out!! Very enlightening and saves me a ton of discovery on my own. That said I'll be moving forward with the project. Remember, I'm going with the "blinding sun" strategy. I don't care about pulse frequencies, jam codes. Looking at always on, like my headlight. I'm going to generate a blinding amount of IR in the 890-930nm range as not to do the Lidar gun any favours. I'm aware it might still be able to pluck out it's own pulses, but as with everything else in life - it's all relative... time, conditions, distance, aim, etc... all plays into the Lidar device being successful and at what range. I cannot see a LEO standing at 1000ft away, but at 500ft I might have a fair chance to police myself if I happen to be out of the posted limits. On a bike we can accelerate and break much quicker than cars and it's easy to get complacent without even trying. If I can achieve even a 30-50% reduction in acquisition or accuracy I'd consider it a success.

I'm in the Tampa Bay area. I would like to ask if anyone near me has LiDar equipment to help my experiment. I'd like to test this IR blinder along with IR rejecting headlight film on my bike. It would be greatly appreciated and helpful to all on this board. Please let me know - and won't punk out like in that other thread.

**TimeBandit** · 05-04-2010 06:01 PM

Update:

The IR flood unit is assembled and blinding with IR. It's putting out 9,600 miliwatts (mw) in the 890nm peak plus 21,600 mw in the 940nm peak. That's roughly 31.2 Watts of LED power - but to put that in human perspective, it's like 125 Watts of *incandescent* light. I know I'll take some heat on that 125W claim but it's only for illustration and not factual. For example, if you wanted to replace a typical 125W incandescent light in your house with a LED bulb of comparable light output, you'd build an array of white LEDs that would consume roughly 31 watts of power - that's all I'm saying.

The mixture of 890nm and 940nm - both LEDs cross into the 905nm range, so I hope there is enough to drown that down.

So, I have this really bright IR spot light.... Now what?

I need some field testing... Anyone.... Bueller... Anyone?

**jimbonzzz** · 05-04-2010 09:41 PM

Post what area (state etc) where you live. Maybe one of the members with laser guns would be willing to meet up with you.

**Stealth Stalker** · 05-04-2010 09:52 PM

Originally Posted by TimeBandit

On a bike we can accelerate and break much quicker than cars ...

Nice Freudian Slip.

**AirMoore** · 05-05-2010 11:19 AM

Originally Posted by jimbonzzz

Post what area (state etc) where you live. Maybe one of the members with laser guns would be willing to meet up with you.

He is in the Tampa Bay area...

Maybe some forum members nearby are willing to help...

**wag** · 05-06-2010 04:43 PM

I'm not so sure that I would want to be riding a scooter with a device on it that sets off the radar/laser detectors in every car around me.

**jimbonzzz** · 05-06-2010 09:17 PM

Originally Posted by wag

I'm not so sure that I would want to be riding a scooter with a device on it that sets off the radar/laser detectors in every car around me.

A CW laser source won't set off any laser detectors. It also isn't going to offer any level of protection against laser speed measurement. But I really do hope one of the board members helps him test it, if for no other reason than to serve as an example for others.