1. Lens Technologies

2. Microscopes Invented by Johannes and Zacharias Jansen in 1590 Larger inverted image Used in study of cells and diseases

3. Refracting Telescopes: Galileo and Kepler

4. Reflecting Telescope: Newton’s Innovation Reduced chromatic aberration

5. Modern Telescope http://www.youtube.com/watch?v=0jPE7u3bz _E http://www.youtube.com/watch?v=0jPE7u3bz _E

6. Binoculars Two refracting telescopes Total internal reflection Longer light path results in better magnification

7. Sight & Human Eye

8. Structure – Human Eye Cow Eye Dissection - http://www.youtube.com/watch?v=hZ4mUMsMfTQ&feature=related http://www.youtube.com/watch?v=hZ4mUMsMfTQ&feature=related

9. Focussing – Human Eye Ciliary muscles make the lens shorter and thicker to focus a nearby object Relaxed eye lens focusses on a distant object

10. Eye vs. Camera

11. Correcting Vision Using Lenses Common causes of poor vision: Incorrect shape of eyeball Incorrect shape of cornea Hardening of the lens Corrected by: Glasses Contact lenses Laser eye surgery

12. Myopia – Near Sightedness Long eyeball results in image formation in front of the retina Rays spread again and result in blurry image

13. Hyperopia – Far Sightedness Short eyeball results in reaching of light rays at the retina before they converge Blurry image

14. Presbyopia Symptoms often like Hyperopia (far sightedness) Aging causes ciliary muscles to be less flexbile and can no longer make the lens change shape to focus on objects at different locations Solution is bifocals.

15. Astigmatism Cornea is oval shaped instead of spherical. Causes light to focus on two or more spots.

16. Night Vision Devices You tube rescue with Night Vision Aid (40 sec. long) http://www.youtube.com/watch?v=u- 6Vd1gc8AA You tube night vision goggles (3 minutes long) http://www.youtube.com/watch?v=BOpJzH0 XX-c http://www.youtube.com/watch?v=BOpJzH0 XX-c

17. Optical Illusions

23. Animated Optical Illusions http://www.youtube.com/watch?v=lvvcRd wNhGM http://www.youtube.com/watch?v=lvvcRd wNhGM http://www.youtube.com/watch?v=T5xtR dLOopU http://www.youtube.com/watch?v=T5xtR dLOopU

24. I “Speye” Activity & Homework p. 514 - Complete Part 1 – 3 with a partner p. 511 # 4, 5 and 8