How is optical power in lenses defined?

How is optical power in lenses defined?

• A. As the sum of focal lengths
• B. As the product of radius and thickness
• C. As the inverse of the focal length in meters
• D. As the ratio of image distance to object distance

Answer: (C)

Optical power in lenses is defined as the inverse of the focal length measured in meters. This relationship is fundamental in optics, whereby the power (measured in diopters) quantifies how strongly a lens converges or diverges light. A lens with a short focal length has a high optical power, meaning it focuses light rays more sharply, while a lens with a longer focal length has lower optical power. The formula for calculating optical power (P) is given by: P = 1 / f where P is the power in diopters and f is the focal length in meters. This definition is essential when working with lenses because it directly impacts lens design and applications, such as in eyeglasses or cameras. Understanding this principle helps in various practical applications, such as designing optical systems, determining the appropriate lenses for specific uses, and predicting how light will behave when interacting with different lens designs.

Optical power in lenses is defined as the inverse of the focal length measured in meters. This relationship is fundamental in optics, whereby the power (measured in diopters) quantifies how strongly a lens converges or diverges light. A lens with a short focal length has a high optical power, meaning it focuses light rays more sharply, while a lens with a longer focal length has lower optical power.

The formula for calculating optical power (P) is given by:

P = 1 / f

where P is the power in diopters and f is the focal length in meters. This definition is essential when working with lenses because it directly impacts lens design and applications, such as in eyeglasses or cameras.

Understanding this principle helps in various practical applications, such as designing optical systems, determining the appropriate lenses for specific uses, and predicting how light will behave when interacting with different lens designs.