Tycho never had a telescope to use. All of his observations
were so-called "naked-eye" observations.
convex lenses are for short sighted people.
A convex or converging lens can fix eyes with long sighted vision. A person who is long sighted cannot focus on near objects which can be corrected by wearing a convex lens.ÊÊ
A concave lens is thinner at the centre. People who are short sighted often use a concave lens to help them see better.
Short sighted people are not helped by lenses or anything else. Except the consequences of their short sightedness. I think you mean near sighted people. The eye is a lens and focal point system. The focal length of the eye can be manipulated by flexing muscles in the eye socket to change the distance between the lens and the back of the eyeball. A near sighted, or even a far sighted, person has an eyeball that is too long or too short for the lens, and therefore the image produced by the eye's lens is focused either in front of or behind the back of the eye. A lens, either in a pair of glasses or a contact lens, can assist the eye by effectively pre-focusing the image that enters the lens of the eye to a sharpness that can be accommodated by the focal length of the malformed eyeball, focusing the image sharply on the back of the eyeball. - wjs1632 -
A long-sighted eye has a lens of insufficient power so that it needs an extra convex (magnifying) lens to bring objects into focus. A more powerful lens allows objects to be focussed at a closer distance, and that is what a magnifying glass does.
A person who is farsighted needs a converging lens, which is a convex lens, to help focus light properly onto the retina. This type of lens helps to converge incoming light rays so that distant objects can be seen more clearly.
If you are near sighted u can see close but not at distances so you would have to use a negative lense in glasses or contacts such as -1.25
im not sure. probably... far sided.
Short Contact Lencesnear sight is hyopia
Image formed by a concave lens or a diverging lens is virtual,upright and smaller than the object.It is used by short sighted people.
Cannon is sighted as being one of the best manufacturers of camera's and camera related items such as lenses. Nikon also makes a high quality lens system.
Short sightedness (or myopia) occurs when the eye focusses the image in front of the retina. A minus powered lens is used to bring the image forward and so into focus.It is easily correctable with glasses, contact lenses or laser surgery.