Report on Holograms

The upcoming IMMERSION 2015 has a history of successful previous 9 years of Immersive Education, iED, conferences. While Paris has been selected as the official site for IMMERSION 2015, the summit will address the individual and cultural influence of immersive technologies such as Virtual Reality, augmented reality, wearable computing, cybernetics, and etc. For more information on new forms and technologies at summit, this website http://summit.ImmersiveEducation.org should be helpful and accurate.

Hologram is a technique that enables 3D, three dimensional, images to appear. This technology requires the use of laser, interference, diffraction, light intensity recording and suitable illumination of the recording. The image like presentation by the holography is not an image. It consists of a random structure of either varying intensity, density or profile.

           Hologram is recorded using a flash of light that recreate a scene and imprints on a recording medium. Hologram also requires a laser as the light source. Unlike natural lights such as sunlight, lasers can be controlled by humans and have a fixed wavelength. To stop external light coming in, holograms are usually taking in darkness and it requires specific exposure time.

  An amplitude modulation hologram is one where the amplitude of light diffracted by the hologram is proportional to the recorded light intensity. One great example of this is photographic emulsion on a transparent substrate. The more light fell on the plate at a given point, the darker the developed plate at that point would become.

           

A phase hologram is made by changing either the thickness or the refractive index of the material in proportion to the intensity of the holographic interference pattern. This is called a phase grating, which is shown when such plate is illuminated by the original reference beam. It reconstructs the original object wavefront. Phase modulated holograms are more efficient than the amplitude modulated ones.

            Electron holography is the application of holography techniques to electron waves instead of light waves. Invented by Dennis Gabor, electron holography is to improve the resolution and avoid aberrations of the transmission electron microscope. The principle of electron holography can also be applied to interference lithography. 

            Acoustic holography is used to estimate the sound field near a source by measuring acoustic parameters away from the source through an array of pressure and particle velocity transducers. Techniques included within acoustic holography are becoming increasingly popular in various fields such as transportation, vehicle design, and NVH.

            Microsoft HoloLens is a smart glasses that is wireless, self-contained Windows 10 personal computer. It uses advanced sensors, high definition 3D head-mounted display, and spatial sound system for augmented reality. Applications for Microsoft HoloLens include HoloStudio, a 3D modeling for 3D printers, an implementation of the Skype, Holobuilder and etc.