Optical devices come in a wide variety of shapes sizes, uses and materials. They range from the medical, recreational and scientific venues. Optical devices come in two different forms, near and distance. Near devices were designed for the magnifying of close objects and small hard to read prints. Distance devices serve the purpose of magnifying things from great distances (ranging from anywhere from 6 feet to far away).
Let’s look at the first group, near magnifiers. These devices are designed to be hand held, placed on an object or mounted. These help enlarge prints and words for easier distinction. Stand magnifiers are extremely strong lenses that remain mounted on a plastic stand. The stand magnifier is easier for children to use. It can be moved all the while still resting on a page of a book. They can be used for a variety of tasks like reading labels and signs, measurements and the inspection of random objects. The other optical devices that come in handy are distance magnifiers which can be like little telescopes. They improve someone’s ability to see distant objects, people and to distinguish landmarks. Objects appear to be closer which makes it harder to judge distance properly.
It is best not to use telescopes while walking around seeing that your vision is fixated at a distance and can’t see close by. The application of telescopes has aided astronomers for hundreds of years. Many physicists also rely on optical devices for their studies involving gravity and the laws of gravity which affect our solar system and everything in it. Other more recent break throughs with optical devices involves night vision. Night vision is simply having the ability to see at night. Some animals, like cats have amazing natural night vision.
We humans do not. We rely on technology to make this possible. Night glasses are binoculars with large diameter objective. These large lenses gather the light and concentrate it to assist in making what you see brighter. The lenses act as a larger human pupil so the more light gathered the better you see in the dark. Before the invention of other night vision technology night glasses were the only method of non-natural night vision. These glasses saw a lot of action with the Navy and Coast Guard during World War 2.
The main problem with these types of optical devices is their size and weight which can make them extremely cumbersome and uncomfortable to operate.