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Learn about the properties, types, and functions of convex and concave lenses in optics, including refraction and focal points.
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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.
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 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)
convex lenses concave lenses
The refracted rays converges / diverges and meet at a point.
The refracted rays converges / diverges and meet at a point. Convex lens F focus (焦點)
The refracted rays converges / diverges and meet at a point.
The refracted rays converges / diverges and meet at a point. Concave lens F focus (焦點)
Focus (焦點) and Focal Length (焦距) F C focal length
thinner lens => f is longer thicker lens => f is shorter
Class Exercise 9.1 1 cm focal length = ?
Class Exercise 9.1 1 cm focal length =3 cm (2.8 – 3.2)