1. Ch.6 Lens (透鏡)

2. Convex Lens (凸透鏡) and Concave Lens (凹透鏡)
A lens is made from _________________ materials usually
made of glass. Their surfaces are _______________.
(b) There are two types of lenses:
_____________ lenses (凸透鏡) and ___________ lenses
(凹透鏡) .
(c) Convex lenses are thicker in the middle than at the edge.
Concave lenses are thinner in the middle.
(d) When light rays pass through lens, _______________
occurs.

3. Convex Lens (凸透鏡) and Concave Lens (凹透鏡)
transparent (透明)
A lens is made from _________________ materials usually
made of glass. Their surfaces are _______________.
(b) There are two types of lenses:
_____________ lenses (凸透鏡) and ___________ lenses
(凹透鏡) .
(c) Convex lenses are thicker in the middle than at the edge.
Concave lenses are thinner in the middle.
(d) When light rays pass through lens, _______________
occurs.
curved (彎曲)

4. Convex Lens (凸透鏡) and Concave Lens (凹透鏡)
transparent (透明)
A lens is made from _________________ materials usually
made of glass. Their surfaces are _______________.
(b) There are two types of lenses:
_____________ lenses (凸透鏡)
and ___________ lenses (凹透鏡) .
(c) Convex lenses are thicker in the middle than at the edge.
Concave lenses are thinner in the middle.
(d) When light rays pass through lens, _______________
occurs.
curved (彎曲)
convex
concave
refraction (折射)

5. convex lenses
concave lenses

6. Optical Centre (光心) and Principal Axis (主軸)

7. Optical Centre (光心) and Principal Axis (主軸)

8. Experiment (實驗) 9.1

10. The refracted rays converges / diverges and meet at a point.

11. The refracted rays converges / diverges and meet at a point.
Convex lens F
focus (焦點)

12. Experiment (實驗) 9.2

14. The refracted rays converges / diverges and meet at a point.

15. The refracted rays converges / diverges and meet at a point.
Concave lens F
focus (焦點)

16. Focus (焦點) and Focal Length (焦距)

17. thinner lens
=> f is longer
thicker lens
=> f is shorter

18. Class Exercise 9.1
1 cm
focal length = ?

19. Class Exercise 9.1
1 cm
focal length = 3 cm (2.8 – 3.2)