Thin Lenses

Question 1

Forms of lenses

Answer 1

Plano-concave |( and Plano-convex |)
Equi-convex () and equi concave )(
Meniscus ((

Question 2

Define: Front and Back vertex

Answer 2

Front vertex: where the optical axis of the lens intersects the front surface.

Back vertex: where the optical axis of the lens intersects the back surface.

Question 3

Define: Optical axis and Centre thickness

Answer 3

Optical axis: perpendicular line to the surfaces that passes through the centre of the lens, joining the centre of curvature.

Centre thickness: is the thickness of a lens in the centre

Question 4

Define: Radii of curvature and Centre of curvature

Answer 4

Radii of curvature: is the distance from the centre of the sphere (centre of curvature) to the edge.

Centre of curvature: is the centre of the sphere lens.

Question 5

Optical centre

Answer 5

Optical centre: centre of the lens in which the principal axis passes through and the point where the light rays pass though without deviation or aberrations.