Night-vision glasses work by capturing tiny amounts of light, some of it from the infrared portion of the light spectrum, and amplifying it in order to create an image that is more easily observed. Some systems may also utilize thermal imaging technology, either alone or in concert with light amplification.Know More
Night vision devices capture a minute quantities of visible light through a special component known as an image intensifier tube. This tube utilizes both a conventional lens and a photocathode to convert photons into electrons which are then amplified through the use of a microchannel plate. The amplified electrons that exit the image intensifier tube strike a plate that has been coated with phosphors in order to create a visual image. This image is then viewed through an ocular lens which provides additional magnification and focus.
Thermal imaging devices make use of a lens which collects light from within the infrared spectrum. Once this light has been focused, it is scanned by a phased array of infrared-detector elements. These elements are able to create a detailed pattern based called a thermogram which is then translated into electrical signals. A signal processing unit is then used to create an observable image that is based on the information contained within the thermogram.Learn more about Glasses & Contacts
Regular cleaning is necessary to see well through glasses. Cleaning eyeglasses is easy: simply spray both lenses with eyeglass cleaner, and wipe them with a soft lens cloth.Full Answer >
Tighten loose glasses by pressing the area near the temples slightly inward. Metal frames can be directly adjusted, while plastic frames need to be warmed before manipulation.Full Answer >
Reading glasses are available in pharmacies or the pharmacy section of grocery stores and retailers such as Walmart, Target, Sears and Costco. Consumers also can purchase reading glasses on through an eye doctor.Full Answer >
The standard method to correct secondary cataracts is YAG laser capsulotomy, not glasses, according to the American Optometric Association. This is a type of laser surgery sometimes performed on the membrane that remains after traditional cataract surgery. As the membrane turns cloudy, vision worsens.Full Answer >