A manufacturer is designing a compact digital camera in which the distance between…
PHYSICS · Multi-part · CBSE · Physics · Light — Reflection and Refraction · Light — Reflection and Refraction
Problem
A manufacturer is designing a compact digital camera in which the distance between the lens mount and the image sensor is mechanically fixed at 35mm. The camera must be able to focus sharply on very distant objects (assume the objects are effectively at infinity) as well as on nearby objects located 2.0m from the lens. Assume the camera uses a single thin convex lens placed at the lens mount.
(a) Determine the maximum focal length the manufacturer can choose so that a distant object forms a sharp image on the sensor without moving the lens relative to the mount.
(b) With the focal length found in part (a) fixed, calculate how far the lens must be moved away from the sensor (along the optic axis) to bring an object at 2.0m into focus.
(c) For the nearby object in part (b), compute the lateral magnification and state whether the recorded image on the sensor is upright or inverted relative to the object.
(d) Discuss one design advantage and one design drawback of selecting a focal length equal to the value you calculated in part (a), compared with choosing a significantly shorter focal length while keeping the same fixed sensor distance.