A lens has many uses. With the right shape a lens can correct someones eye sight or with multiple lens you could even make a telescope. But for all uses of a lens it comes down to one job. The distortion of light.
The basic equipment needed for a photographers job is a good SLR (single lens reflex) camera. Deprnding on the type of work undertaken, different types of lenses will be needed such a zoom/telephoto lens or a macro lens. As well as this, other accessories are useful such as lighting, tripod and a computer to view any digital photos.
Typically a "fast" lens with a maximum aperture of f2.8 or better (1.8). But if you have time for a longer exposure or can accept the grain/noise of higher film speeds, the lens you have can do the job. of course if you want to kibbitz there are the magical and mythical 1.0 lenses too
The lens allows for creating different effects on the camera. There are lens for zooming, fish eye, etc. It creates different artistic modes. The camera comes basically without the lens, and more experienced photographers by other lenses for the new effects. They are a lot of fun though, I would definitely recommend investing in them, they create many more opportunities to have fun with Photography.
It is lens. The lens consists of the lens capsule, the lens epithelium, and the lens fibres.
The ocular is the upper lens and objective is the lower lens
)( is a concave lens() is a convex lens
The objective lens
Converging lens is a convex lens.
if you are using A+ it is lens
A crystalline lens is the lens in the human eye.
Double-convex lens