RF Transmissivity Question

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

That is a black painted mask that prevents the UV rays from breaking down the adhesive that is used to mount the windshield. Its speckled on the edges to blend in.

Laser yes, radar probably. The Tint also affects performance.

Cheers

It is simply an optical attenuator. As in looking at the mirror at a specific orientation could have the sun just past it. That keeps the glare from happening, allowing one to utilize the mirror trouble free. Optically speaking.

I doubt seriously that it was metallic ink or that it would be anything other than transparent to RF.

It doesn't appear to be a radio antenna. Possibly a sun screen to block sunlight that would otherwise leak between the sun visors and interfere with the use of the rear view mirror.

Depends on what its made out of. If its metallic, then I'd guess 'Yes'.

Find one of those annoying radar speed signs (fixed, low power, continuous source*). Park just at the threshold of your detector's picking it up. Move the detector back and forth from behind this screen to clear windshield and see if that makes a difference.

*Be careful about assuming that these signs use a constant transmit level. One in my neighborhood pulses until it detects an oncoming vehicle. Then it switches to continuous mode.

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Paul Hovnanian  paul@hovnanian.com
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Have gnu, will travel.

Maybe. Usually, that's paint intended to screen sunlight, and one common pigment is hematite (Fe2O3). It makes dollar bills magnetic (the black ink), laser toner readable by magnetic sensors, and reflects microwaves.

The layer is thin and perforated, so the effect is more reflection than attenuation.

Retarded UnAmerican asshole buys foreign, and then calls everyone else "leftist weenies".