Radar detectors, for its reliable functionality, has to have an access to radar waves from radar sources. The standard windshield absorbs radar waves in negligible percentage. A problem occurs if there is an obstacle on the way to the detector that could bounce off the signal.The typical example is athermic/metal plated windshield on some vehicles.
Why are some cars equipped with athermic windshields? The answer is simple, a thin and almost 100% transparent layer of metal plating is able to bounce off, not only the radar waves but also a certain spectrum of solar sunlight that is coming into the vehicle. Such windows can reduce the amount of heat inside the cabin and contribute to the passenger's climate comfort.
Let's have a closer look at various types of windows used in the industry.
Portable radar detectors vs. athermic/metal plated windshield
The athermic windshield can be recognized by slightly green/blue/ magenta tint when you look at the car from a specific angle. The easiest way to tell is when you look at the windshield with polarized sunglasses that can highlight the effect. Various automotive brands use different designations such as Athermal, dethermal, Sun safe, Sun protect, Microclimatic window etc. These types of windshields practically make the use of portable detectors impossible. These metal plated windows can reduce the radar signal in up to 95%, lowering the detection range from hundreds of meters to just a few meters.
In this case, there are only two solutions. Either an exchange of the windshield for a standard variant, some car models, however, does not offer classic windows at all. The second option is, buying one of the custom installed sets, where the radar antenna is installed in the car's front bumper.
Portable detectors vs. heated windshield
The heated windshield is recognizable by very thin stripes of wire running usually vertically through the entire glass. Those stripes are thin as a human hair and at a distance of few millimeters to each other. heated windshields have minimal impact on the function of portable detectors and reduce the signal waves in approximately 1-3 %. With modern detectors this signal loss is imperceptible. Simply to say heated windshields are no threat for modern detectors.
Portable detectors vs. safety/anti-solar tinted windows
Tinted windows or windows with safety film is not a problem for radar detectors. Most of the films used in the industry does not have metal plating and therefore, the radar waves can go through with no loss. If you are looking for a discreet place for you portable detector you can easily install it behind an anti-solar stripe in the top of the windshield.
Fix installed radar detectors vs. obstacles
The radar antenna from the custom installed set is usually mounted behind a plastic part of the cars front bumper, eventually into the front grille. When placing the antenna it is necessary to take in mind that no metal obstacles should be in its way, such as the metal supports, registration plate, light washer tubes or chrome plated parts of the car's bumper.
Long story short, does your car has metal plated - athermic windshield? You will need a custom installed system. Any other type of windshield won't be a problem for your portable detector.