Anti-photo license plate covers, such as Chameleon, Super Protector, etc. are passive devices that cause the camera flash reflection to be dispersed away from the camera, so that the received picture is not recognizable to the human eye. We see light wavelengths between 425 nanometers and 700 nanometers, low blue to high red colors. The passive devices scatter the reflected light enough that our eye can not discern the original image. These passive devises worked to defeat older, ProDB_Wavelengths_horizontalnon-digital, speed camers; but they can not defeat a digital camera, because digital cameras have a much wider view of the light spectrum between 250 nanometers to 1100 nanometers wavelength. The 250 nanometer wavelengths are ultra-violet colors below our vision of blue; while the 1100 nano-meters are infrared colors, well above our red vision. The anti-photo plates are made of plastic with a lens either designed into the plastic or attached to the plastic cover. The anti-photo plate is bolted against the license plate and the lens is designed to scatter the reflected light reflected off the plate away from the camera aperature. This is effect obscures the alpha-numeric characters from the camera, typically located at an angle of 20-30 degrees from the side of the road. This is the typical angle that photo cameras are installed on the side of the road, but can also be installed above the road on bridges or poles. The plates will distort the plate characters at all times from the side of the road, or from above the road, but not both. Police do not appreciate this as they drive by your vehicle and are not able to see your plate for a short period of time. In most states, this is called obfuscation; i.e., hiding the plate, and the police will write a ticket in many instances when they see a dark cover or a lens over the plate. When a bright light is pointed at the anti-photo cover as with a camera flash, the distorted characters will not show up in the photo image under non-digital photo imaging. If an analog picture camera is used these types of anti-photo covers will work, but all digital cameras today are digital, which makes the anit-photo plate useless. When digital imaging is used, as with speed cameras today, these types of anti-photo plate covers are worthless, as discussed above. Photo Sprays, such as Photo Fog, Photo Spray (an endless number of product names) are designed to spray (via hand pump or pressurized can) a liquid over the surface of your license plates. 99.999% of the customers do not realize that this type of material is very close to a hair spray product, or is a hair spray product, re-packaged in a new can with a different name. (I wonder what is going through your mind at this point) Liquid chemicals such as this or hair spray, are emitted as a liquid and when the liquid drops contact a surface, (whether hair or a metal plate), the liquid will evaporate, forming millions of ultra-small crystals, which are cubicle in form. When a bright light is pointed at the plate as with a camera flash, the millions of ultra-small crystals on the license plate will cause a very bright reflection to the camera; in effect blinding the camera. The photo camera’s normal operation is to use radar (sometimes laser) to detect the speed of oncoming vehicles. When detecting a speed greater than the set point of the camera (posted speed limit), the radar will command the camera to trigger at the right moment in time, no matter how fast you are driving, and take a photo of the plate (and the driver, if the camera is set up for oncoming traffic). The image is then sent by email to a processing facility, or the data is stored on some sort of memory device and picked up from time to time by an operator. The images are then compared to a local data base, and a speeding ticket, based on the speed of the vehicle, is mailed to the registrant. When an image from a license plate protector or photo spray is encountered, the image can be easily inversed using standard digital photo programs to bring out the alpha-numeric characters, and the driver still gets a speeding ticket. So much for the anti-photo plates and anti-photo sprays. Photo Blockers come in two designs, both using a flash detector and bright flash to either prevent the speed camera from getting your license plate image ( blind the plate from the camera image). One active Photoblocker will flash back at the camera to blind the camera and any body who happens to be looking in the direction of the active photo jammer. This type of flash back photo blocker is a hazard to other drivers. The 2nd type of photo blocker (ProDB-2) detects the ProDB_Truck_Minibright flash, but rather than flash back at the camera, the flash is directed over the license plate, causing the alpha-numeric characters to become totally white, no matter what color the characters are. Because this flash is directed downward, it achieves the jamming in a safe manner, and blinds only the license plate from the camera image. In either case of active photo jamming, the plate is always visible to any police who happen to drive by. When the active photo jammer detects a flash, the photo camera gets a picture of bright white light, thus it does not matter if the image is inversed electronically; since the image is white, the inverse of white is black. All the camera will get is white in normal imaging mode, or black in an inverse image mode, thus a speeding ticket can not be mailed to the registrant of the vehicle using an active Photo blocker. If you use the license plate covers, or a photo spray liquid, it may be a lot less expensive, but you are only giving your money away, since the operators know they need only push a button to inverse the photo image to get the license plate image. Cheap thrills! You still get a speed camera ticket, even though you paid $29.95, the typical cost of the spray or license plate cover. Click here for photo blocker.