1. Function, Structure, Focus, Vision Correction
The Eye
Function, Structure, Focus, Vision Correction

2. The Ear vs. The Eye
Mechanical Sound Waves with frequency range of 20-20,000 Hz
Non-Mechanical Electromagnetic Waves in the Visible Light Range (4.3 x 1014 to 7.9 x 1014 Hz)
Focus (pinna focuses sound waves down ear canal)
Transfer (ear drum vibrates and causes the 3 tiny bones to vibrate)
Interpret (cochlea resonates)
Send Signals (aural nerves send impulses to the brain
Focus (Cornea refracts light: initial focus through fixed convex lens)
Transfer (through the pupil with 2nd refraction through lens (moveable)
Interpret (light transferred to retina: cone cells color)
Send Signals (optic nerve sends impulses to the brain)

5. Stare at bird for 30 s and look to left—what color is the ghost image?

6. Stare at bird for 30 s and look to left—what color is the ghost image?
Cyan (blue light + green light)
Your red cone receptors
are fatigued, so you
only perceive cyan.

7. The Eye and its Structure
Focusing lenses (double convex lens system)
Cornea (convex lens)--main focusing, fixed
Lens (convex lens)—fine focusing, adjusts
Pupil (light regulator)
Retina (back of eye)
Rod cells (senses intensity)
Cone cells (red, green
and blue light receptors)

8. Rods and Cones in the Retina
Retina (back of eye)
Rod cells (senses intensity)
Cone cells (red, green and blue light receptors)
Photochemical Reaction produced when frequencies of visible light are absorbed

9. Rods and Cones in the Retina
Retina (back of eye)
Rod cells (senses intensity)
Cone cells (red, green and blue light receptors)
Photochemical Reaction produced when frequencies of visible light are absorbed—peak at red green and blue, but produce all colors based upon intensity as well as frequency

10. Rods and Cones
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11. Colors:additive and subtractive

12. The Eye and its Structure
Focusing lenses (double convex lens system)
Cornea (convex lens)--main focusing, fixed
Lens (convex lens)—fine focusing, adjusts
Pupil (light regulator)
Retina (back of eye)
Rod cells (senses intensity)
Cone cells (red, green
and blue light receptors)

13. Rods and Cones
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14. What is color?
When we see color, we are seeing specific frequencies of visible light
VISIBLE LIGHT IS ROYGBIV
Red, orange, yellow, green, blue, indigo and violet
For visible light
Red has the lowest frequency and longest wavelength
Violet has the highest frequency and shortest wavelength

15. 28.2 Color by Reflection
This square reflects all the colors illuminating it. In sunlight, it is white. When illuminated with blue light, it is blue.
This square absorbs all the colors illuminating it. In sunlight it is warmer than the white square.

16. Why a shirt appears blue.
A blue shirt appears blue in white light because it reflects only blue and absorbs red and green (or the other colors)
A blue shirt appears black in red light because it absorbs red and reflects nothing.
A blue shirt appears blue in blue light because is reflects blue.
A white shirt appears blue in blue light because it can reflect blue light.

17. Why a shirt appears blue.
A blue shirt appears blue in white light because it reflects only blue and absorbs red and green (or the other colors)
A blue shirt appears black in red light because it absorbs red and reflects nothing.
A blue shirt appears blue in blue light because is reflects blue.
A white shirt appears blue in blue light because it can reflect blue light.

18. Colorblindness
Colorblindness is a deficiency in the number of red, green or blue cones (too few of one or more cone types).
Colorblindness
Normal vision

19. http://www. colblindor

22. Better Eyes

23. Rods and Cones

24. What is color?
When we see color, we are seeing specific frequencies of visible light
VISIBLE LIGHT IS ROYGBIV
Red, orange, yellow, green, blue, indigo and violet
For visible light
Red has the lowest frequency and longest wavelength
Violet has the highest frequency and shortest wavelength

25. 28.1 The Color Spectrum
When sunlight passes through a prism, it separates into a spectrum of all the colors of the rainbow.
roygbiv

26. The pupil regulates the intensity of light entering the eye
Both the cornea and inner lens are convex (convergent) lenses
The retina contains rod and cone cells that are photosensitive to different frequencies of visible light. Red-green-blue cone cells are the color receptors

29. 30.6 The Eye
Inner lens moves to focus close up and far away images

30. Concave lens
Convex lens

31. Vision correction Corrected by divergent (concave) lens
Corrected by convergent (convex) lens

32. Concave lens
Convex lens

33. CONCAVE AND CONVEX MIRRORS
Convex mirror causes light rays to converge.
Concave mirror causes light rays to diverge.