There are a number of different spy sunglasses that can be purchased and used to achieve a variety of results. One of the most common and inexpensive types of sunglasses that can be used for spying have special lenses that allow the wearer to look behind himself or herself. There are also sunglasses that have a camera built into the frame, allowing the wearer to secretly record everything he or she looks at. Some spy sunglasses can be designed with a small display on the inside of the lenses, which could be connected to an external camera and display whatever is seen by the camera.
Spy sunglasses are typically sunglasses worn for a variety of purposes, though often to remain unnoticed or to achieve certain covert goals in secrecy. These sunglasses can be worn by actual spies, or by individuals who are interested in personal security, as well as by people pretending to be spies and children who are playing. The ways in which spy sunglasses function can differ wildly, though dark sunglasses are a classic aspect of the overall spy image and mystique.
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One of the most common types of spy sunglasses are the ones that allows a spy to see behind himself or herself while they are worn. These sunglasses typically consist of dark lenses that do not allow others to see the eyes of the wearer and otherwise appear like normal sunglasses to viewers. Most spy sunglasses like this, however, feature small reflective areas at the outer edge of one or both of the lenses. By looking at this reflective area, rather than straight through the middle of the lenses, the wearer can see a reflection of the area behind him or her. These glasses can be a great way for anyone to remain aware of his or her environment, including runners or bicyclists who can use the glasses as a wearable rearview mirror.
More expensive and sophisticated types of spy sunglasses are those that include a hidden camera in them. These sunglasses have a small camera built into the frame of the glasses, often located on the bridge of the nose. Such glasses can use a still image camera, often operated by a hidden hand-held device, or a video camera that captures images over a period of time. The location of the camera in the glasses allows it to record whatever the wearer is looking at.
Even more sophisticated spy sunglasses utilize a small monitor or display on the inside of the lenses. This will usually have a wire that can be used to connect the glasses to an external device to view images from that device. If these sunglasses are connected to a small camera, then whatever is captured on the camera could immediately be viewed as a live feed by the wearer of the glasses.