1. ## why not angle your plate?

Years ago, I noticed my uncle put some 1" spacers behind only the top mounting holes of his front license plate. He said it was to throw off a laser gun and have the reflection go down into the ground instead of coming back to the officer.

I realize officers have other choices to aim at (headlights, grill, etc.) but would this work to prevent a laser hit right at the plate?

What angle of reflection does the gun need to be at for the laser light to come back?

You can probably achieve 15 degrees using this method, and on some cars the top edge is already a little further forward than the bottom just because of the OEM mounting bracket. So you might have as much as 20-25 degrees relative to perpendicular with the ground on some cars.

Thoughts?
Brian

2. ## Re: why not angle your plate?

When doing laser jammer testing, I measure out the length of the course, as well as key landmarks along the course, by shooting signs and other objects along the road. When I shoot at signs that are perpendicular to the road -- meaning they point almost 90 degrees away from where I am shooting from -- I still have no problem getting a reading off of them, and they aren't even reflective signs.

Like Veil, I think angle does make some difference, but not enough to make a difference on it's own.

3. ## Re: why not angle your plate?

In your test scenario, I understand the signs are perpendicular to the ground. 90 degrees to the ground. Isn't that the most optimal angle for the laser to work at?

Standing 20' from a stop sign with your flashlight. Almost all light comes back to your face. Now take that stop sign and bend the post down towards the ground. Most of the light hits the ground, doesn't come back to your eyes.

Does laser behave differently?

4. ## Re: why not angle your plate?

I always wondered the same thing. Looks like it would be like a mirror and glance off and an angle. Strange that it does not work that way. I am sure someone in here can explain why. I probably won't understand the explanation though.

5. ## Re: why not angle your plate?

Angle in is the angle out?

I don't run a front plate out of state, but if I were to put one on, I would most certainly angle it.

Wondering why this wouldn't work....?

6. ## Re: why not angle your plate?

Most license plates are retroreflective, meaning that they use a material that reflects light back to the source regardless of the angle.

So, angling the license plate isn't likely to have much of an effect, unless it isn't a retroreflective plate.

7. ## Re: why not angle your plate?

Originally Posted by jimbonzzz
Most license plates are retroreflective, meaning that they use a material that reflects light back to the source regardless of the angle.

So, angling the license plate isn't likely to have much of an effect, unless it isn't a retroreflective plate.

exactly that

8. ## Re: why not angle your plate?

x3.

What I was saying was that the signs are perpendicular to me and the gun I am shooting, meaning that they are being shot from an extreme, almost sideways angle, not dead on. If I can get an instant reading on a non-reflective 'house for sale' sign at 1000 feet, then a retro-reflective licence plate at a slight angle is going to be no challenge at all.

Go outside tonight, stand off at a 45 degree angle from the front of your car, and shoot a flash photo of it. You'll still get a plate reflection causing a large white spot on your photo, even at that angle.

9. ## Re: why not angle your plate?

Yep, same thing happens with reflectors on cars.

10. ## Re: why not angle your plate?

Also, the LIDAR beam is reflecting off more then the License plate surface. Infrared beams can reflect of most surfaces. The reason the police target the plate is because that is what they were told to do and second it gives them a single distinguishable point on the car to aim at and they can say they aimed at the plate and only the plate thus staying out of the panning and slip discussion.

My laser range finder works on all sorts of surfaces in my home.

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