Britannica Sources used in this answer

What role does the object beam play in continuous-wave laser holography?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

hologram graphic — holography Figure 1: Gabor's original method for creating holograms.

In continuous-wave laser holography, the object beam plays a critical role in capturing the physical characteristics of the subject. When a coherent laser beam is directed onto an object, the light is reflected, scattered, and diffracted by the object's physical features. This reflected light carries essential information regarding the amplitude and phase of the optical field associated with the object.12

As this object beam arrives at the photographic plate, it interacts with a separate, coherent reference beam. The interference between these two beams creates a complex pattern of interference fringes on the plate. While standard photography only records amplitude, the object beam's interaction with the reference beam allows the hologram to store both amplitude and phase information. This phase information is vital, as it contains the precise data regarding the depths and heights of the object's contours, which enables the reconstruction of a three-dimensional image.132