How can we use lenses to correct vision?. If the image is turned upside down too soon, what lens...
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Transcript of How can we use lenses to correct vision?. If the image is turned upside down too soon, what lens...
How can we use lenses to correct vision?
If the image is turned upside down too soon, what lens would we use?
What if the image was turned upside down too late? What lens would we use?
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
c. Farsightedness- image formed behind retina
a. Normal eye
b. Nearsightedness-image formed in front of retina
Corrected with concave lens
Corrected with convex lens
No correction needed
Eyeball too long
Eyeball too short
Iris: color of eye Lens: double convex Cornea: single convex Pupil: opening that lets light in Ciliary Muscle: opens up pupil in dim light,
closes in bright light
Iris: color of eye Lens: double convex Cornea: single convex Pupil: opening that lets light in Ciliary Muscle: opens up pupil in dim light,
closes in bright light Vitreous humour: transparent jelly of salts
and protein
Iris: color of eye Lens: double convex Cornea: single convex Pupil: opening that lets light in Ciliary Muscle: opens up pupil in dim light,
closes in bright light Vitreous humour: transparent jelly of salts
and protein aqueous humour: is a thick watery
substance filling the space between the lens and the cornea.
Iris: color of eye Lens: double convex Cornea: single convex Pupil: opening that lets light in Ciliary Muscle: opens up pupil in dim light,
closes in bright light Vitreous humour: transparent jelly of salts
and protein aqueous humour: is a thick watery
substance filling the space between the lens and the cornea.
Sclera: white covering
Iris: color of eye Lens: double convex Cornea: single convex Pupil: opening that lets light in Ciliary Muscle: opens up pupil in dim light,
closes in bright light Vitreous humour: transparent jelly of salts
and protein aqueous humour: is a thick watery
substance filling the space between the lens and the cornea.
Sclera: white covering Optic nerve: sends picture to the brain
Retina: the picture is upside down here Made up of millions of tiny, light-sensitive
cells called rods and cones
Retina: the picture is upside down here Made up of millions of tiny, light-sensitive
cells called rods and conesRods: distinguish among black, white
and gray; allows you to see in dim light
Retina: the picture is upside down here Made up of millions of tiny, light-sensitive
cells called rods and conesRods: distinguish among black, white
and gray; allows you to see in dim lightCones: respond to color, 3 types: red,
green and blue. Only function in bright light
Normally, there are three kinds of cones (each one sensitive to a specific range of wavelengths):
"red" cones (64%)"green" cones (32%)"blue" cones (2%)
The normal human retina contains two kinds of light sensitive cells: the rod cells (active only in low light) and the cone cells (active in normal daylight and responsible for color perception).
The different kinds of inherited color blindness result from partial or complete loss of function of one or more of the different cone systems.
Different Types of Color Blindness
Monochromacy: occurs when two or all three of the cone pigments are missing and color and lightness vision is reduced to one dimension.
Total color blindness-see everything as white, black and shades of gray
Dichromacy: occurs when only one of the cone pigments is missing and color is reduced to two dimensions.
Partial color blindnessred-greenblue-yellow