Which of the following is also known as an optical cavity?

• A. Optical Prism
• B. Resonating Cavity
• C. Light Chamber
• D. Optical Sensor

Answer: (B)

The term "optical cavity" is often synonymous with a resonating cavity, particularly in the context of lasers and other optical devices. A resonating cavity is designed to amplify light by allowing it to bounce back and forth between mirrors, enhancing the light's intensity through constructive interference. This structure is critical for the operation of lasers, where the optical cavity supports the oscillation of light waves at specific wavelengths to produce coherent light.

In contrast, an optical prism refracts light and disperses it into its component colors, while an optical sensor detects light and converts it into an electrical signal. A light chamber, while it implies a space for light to exist, does not have the specialized structure or function associated with resonating cavities. Therefore, understanding the nature of resonating cavities as structures that physically confine and enhance light makes it clear why this term is often used interchangeably with optical cavity.