Question

Why is coherent light useful?

Answer 1

Coherent Light: -

1. Coherent light sources are ones that emit light waves with the same frequency, wavelength, and phase, or with a stable phase difference.
2. When maxima and minima positions are fixed and waves are superimposed, a coherent source produces long-lasting interference patterns.
3. In order to observe the effects of interference, we mostly require coherent light sources.
4. The phase difference between the two sources stays constant since coherent sources have the same phase. For interference to be observable and distinct, this is a prerequisite.

Coherent light is useful due to the following reasons: -

1. Coherence, in general, refers to all characteristics of correlation between physical quantities of a single wave, or between many waves or wave packets.
2. Waves' ideal characteristic of coherence allows for stationary interference. The following list includes several scenarios where coherent light is required.
3. Holography, various interferometric configurations, and a few types of optical sensors all make use of coherent light (e.g., fibre-optic sensors).
4. These characteristics are crucial for the coherent beam combining technique as well. Additionally, optical cables that we utilize for internet connections contain coherent lights.