Question

The focal plane of a lens is a plane:

• A. Parallel to the lens.
• B. Perpendicular to the lens.
• C. At a fixed distance from the lens.
• D. At the focal point of the lens.

Hint:

The focal plane is parallel to the principal axis and contains all points where parallel light rays meet after passing through the lens.

Answer 1

The Correct Option is A

Step 1: Defining the focal plane.
The focal plane is the plane where the light rays converge after passing through the lens. It is defined by the focal point and is essential in image formation in optical systems. Step 2: Orientation of the focal plane.
The focal plane is always parallel to the principal axis of the lens. It contains all the points where light rays that are parallel to the optical axis converge after passing through the lens. This plane intersects the focal point. Step 3: Conclusion.
The focal plane lies parallel to the principal axis of the lens, passing through the focal point where parallel light rays converge.