His theory was originally intended to increase the resolving power of electron microscopes. Gabor proved his theory not with an electron beam, but with a light beam. The result was the first hologram ever made. The early holograms were legible, but plagued with many imperfections because Gabor did not have the correct light source to make crisp, clear holograms as we can today nor did he use the off axis reference beam which we will describe later. Laser light differs drastically from all other light sources, man-made or natural, in one basic way which leads to several startling characteristics.
Laser light can be coherent light.
Ideally, this means that the light being emitted by the laser is of the same wavelength, and is in phase. These might be new terms for some of you, so let us form an analogy that might clarify the term coherence . Let's say that you are flying over a freeway at rush hour, and directly below you is a long tunnel that all the cars must go through. Nothing is strange about the fact that all different styles and makes of motor vehicles emerge from the tunnel at differing velocities. A Cadillac at 75 mph, a Volkswagen at 45 mph, a motorcycle at 60 mph, a truck at 40.