Lenses

How The Human Eye Works

• The human eye works similar to a camera.
• A human eye is like a camera with the cornea (transparent part of the eye), which are very similar to a lens cover. The iris and the pupil is similar to the aperture (the hole) of a camera.

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Nearsightedness

• Nearsightedness is a vision condition in which people can see close objects clearly, but objects farther away appear blurred.
• Concave lenses are the lenses that correct nearsightedness.
• Nearsightedness occurs if the eyeball is too long. As a result, the light entering the eye isn't focused, and distant objects look blurred.

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Farsightedness

• Farsightedness (hyperopia) is a common vision condition. It is where you can see objects from afar, but objects close up are blurry.
• The type of lenses that can correct farsightedness are convex lenses.

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how lenses are used in cameras

• Creating a sharp image, a camera lens takes all the light rays that are bouncing around, and uses glass to redirect them to a single point. That creates a sharp image.
• The lens sends the light to the film strip, then the lens directs light to a digital sensor.

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How lenses work in a telescope

• The shape of the lens in a telescope concentrates light. The light is what our eyes see when we look into a telescope.

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concave vs convex

• Concave lenses are the lenses that curve inward. A concave lens separate light rays.
• Convex lens are lenses that curve outward. Convex lens focuses the light rays to a certain point.

SIMILARITIES of convex and concave lens

• A convex lens acts very similar to a concave mirror. Both connect parallel rays to a focal point, have positive focal lengths, and form images with similar characteristics.
• In my opinion, I think that convex lens are more valuable than concave lens, because convex lens make objects larger, and concave lens make objects smaller.

Websites

• www.hopkinsmedicine.org
• www.mayoclinic.org
• www.masterclass.com
• spaceplace.nasa.gov
• byjus.com