No, that’s not true. You can use contact lenses if you have astigmatism, there are special lenses called toric lenses designed specifically to correct it.
Soft lenses cannot correct astigmatism because it only has a sphere lens. For a lens to correct astigmatism it must have both sphere and cylinder lenses. Cylindrical lenses are used to correct the power of the astigmatism at a certain axis, spheres are only capable of correcting power. But it's not exactly true that soft lenses are no good for astigmatism. They are, we call them Toric contact lenses.
I currently wear Freshlook Colorblends contact lenses in honey brown and my original eye color is green. I am very happy with them.
False. A concave lens usually produces virtual images. Concave lenses cause light rays to diverge, so the image formed is located behind the lens and cannot be projected onto a screen.
true
it spreads light rays apart,or it is used in a camera lens.
A convex lens acts as concave lens when it is kept in a medium whose optical density is higher than the lens itself. And the vice-verse is also true .i.e, a concave lens can act as convex lens too .
True. Once focus is achieved with a lower magnification objective lens, a higher power objective lens can be rotated into position without fear of striking the slide because the working distance between the lens and the slide increases with higher magnification lenses.
True.
A convex lens can converge a beam of parallel rays to a point on the other side of the lens. It is useful for reflecting and transmitting light.
TRUE
I Cannot Believe It's True was created in 1983.
Depending on the lens choice, the lens may need to be very close to the sample to focus. This is especially true with the higher magnifications.You don't want to smash the lens into your sample, damaging the sample and the lens.