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What the differences between convex lens and concave lens?
A concave lens helps you see far if you're nearsighted and convex lenses help you see near if you're farsighted.
When a person is far sided do the need a concave lens or convex lens?
Farsighted people use convex lenses to correct their vision.(This is the correct answer!)
How do images formed by a concave lens and convex mirror compare?
Both give diminished, virtual, erect image. Hence convex mirror is used as rear view glass in case of vehicles near by the drivers. Concave lens is used to correct short sightedness.
Should a short sighted person use a concave or convex lens?
This is a lens which is designed to help someone who has problems seeing at distance (myope), the light rays going into your eye are not hitting the fovea (the part of the eye located on the retina which allow you to see clearly) in the proper place, these rays are falling in front of the fovea, so by using a concave ( a minus lens) lens, this moves these light rays by diverging them and moving them back to the fovea which allows for clear vision at distance. At least this is how a concave lens is used optically speaking.this is from winter006: concave mirrors are used in stores and gas stations to see a wider area of the store.It's also called , a Diverging Lens .It is thinnest in the centre and spreads light out , so it gives a diminished image .
How the lens change it shape when foucsing on near objects?
the lens of our eyes is different to the lens of a magnifying glass-it can change its shape from thick to thin
What the differences between convex lens and concave lens?
A concave lens helps you see far if you're nearsighted and convex lenses help you see near if you're farsighted.
When a person is far sided do the need a concave lens or convex lens?
Farsighted people use convex lenses to correct their vision.(This is the correct answer!)
What ocular lens is used for near sight?
The ocular lens used for nearsightedness is known as a diverging lens. It is also known as a concave lens.
Are concave lens for near sighted or far sighed?
im not sure. probably... far sided.
What type of lens is used to correct nearsighted vision?
Using concave lens the short sight problem could be rectified. Near sighted person cannot see the things far away. He can see things only so near to his eyes. The ray coming from the far object would form an image just before retina since the eye ball is elongated horizontally. So to make the image to move backward and fall on the retina, a concave lens is used to diverge the ray and finally the image would fall on the retina. Thus the remedy is possible with concave lens.
What does single vision lens mean?
this means you just have a prescription in your glasses or contacts that are correcting only for just distance correction or near correction. for example, rx could be -1.00 right eye and -1.25 left eye if you take that rx and make it -1.00 ADD +2.00 right eye, -1.25 ADD +2.00 left eye that is a multi focal rx. means correction for distance vision with a bifocal added to glasses for near vision.
Can a single vision lens be made to correct presbyopia without having to go to a bifocal or trifocal lens?
Refine The QuestionBefore trying to answer the question the term "single vision" should be clarified. As I understand it, the term single vision is used by the eye glass industry to describe a single element lens with spherical front and back surfaces. Is that what the questioner means by a "single vision" lens? 1. Single vision lens means -the lens has only one power; Bifocal - two powers; Multifocal or progressive is self explanatory.2. Bifocals/Multifocals are prescribed to give good vision for long as well as short/near .3. Single vision lens can be made for presbyopia, if there is no power for long distance. The inconvenience is that you have to remove spectacles every time you see a distant object.4. Sometimes seperate glasses are prescribed for distance and near if someone is not able to adjust to bifocals.
What structre changes the the shape of the lens for far and near vision?
iris
What are signs of farsightedness?
Depending upon the amount of farsightedness, symptoms can range from none to clear distance vision but blurry near vision, to blurry distance and near vision
What type of lens are need if you are nearsighted?
Lenses can correct vision problems by bending light rays before they reach the eye, in effect moving the focal point of the eye's lens so that it falls upon the retina and creates a clear image. Concave lenses cause light rays to converge and lengthen the focal point for the near sighted eye. Concave lenses are thinner in the middle and thicker on the edges and may be curved on one or both sides. Concave lenses cause light rays to diverge, or spread apart. :)
Why concave lens is the lens could correct the image formed of a nearsighted person?
Human eye is optical miracle.Depending on the distance of the object, we have to change the position of the screen.In case of human eye, screen (Retina) is kept at fixed distance and eye lens is elastic and it becomes more or less thin or thick, so as to adjust image on retina. This phenomena is called accommodation. In near sighted persons lens is more convex than it should be. So we put concave lens in front of eye, so that image of distant object should fall on retina. Human brain is also miracle and after few days, it starts guessing the actual distance of the object.
How do images formed by a concave lens and convex mirror compare?
Both give diminished, virtual, erect image. Hence convex mirror is used as rear view glass in case of vehicles near by the drivers. Concave lens is used to correct short sightedness.
