2. GROUP 4 Firdiana Sanjaya (4201414050) Ana Alina (4201414095) POLARIZATION AND HUMAN EYE

4. EXPERIMENT

6. POLARIZED LIGHT Light in which the electromagnetic vibrations take place in one particular plane.

7. In ordinary (unpolarized) light, the electric fields vibrate in all planes perpendicular to the direction of propagation. After reflection from a polished surface or transmission through certain materials (such as Polaroid), the electric fields are confined to one direction, and the light is said to be linearly polarized.

8. In circularly polarized and elliptically polarized light, the electric fields are confined to one direction, but the direction rotates as the light propagates.

9. USES OF POLARIZED LIGHT Polarized light is used to test the strength of sugar solutions, to measure stresses in transparent materials, and to prevent glare.

10. A NATOMY OF EYE

12. F OCUSING LIGHT RAYS Light rays from distant objects enter the eye parallel to one another Light from close objects diverge

13. P RODUCING AN I MAGE The converging lens produces an inverted image which the brain interprets as being upright

14. M YOPIA ( NEAR - SIGHTEDNESS Inability of the eye to focus light from distan object See close object clearly Image focuses in front of the retina Cause by the distance between lens and reina is too long (long eyeball) Cornea and lens converge light too strongly (strong refractive power))

16. Corrected with a diverging lens Negative meniscus:lens shape where edge of lens is thicker than the middle but modified from a basic diverging lens to make it more cosmetically appealing

17. H YPEROPIA ( FAR SIGHTEDNESS ) Inability of the eye to focus from near object No difficulty seeing distant object Babies are born slightly hyperopic.As eye grows condition fixes itself Image focused behind retina Cause by the distance between lens and retina is too small(short eyeball) Cornea and lens is too weak (doesn’t diverge rays enough)

19. Corrected with converging lens Positive meniscus:lens shape where middle part of lens thicker than the edge but modified from a basic converging lens to make it more cosmetically appealing

20. P RESBYOPIA A form of hyperopia (far sightedness)that occurs with age Cause:eye lens losing elasticity Not a result of eyeball being too short Correct with converging lens

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