A holographic display is a type of 3D display that utilizes light diffraction to display a three-dimensional image to the viewer. Holographic displays are distinguished from other forms of 3D displays in that they do not require the viewer to wear any special glasses or use external equipment to be able to see the image, and do not cause a vergence-accommodation conflict.
Some commercially available 3D displays are advertised as being holographic, but are actually multiscopic.
1947 – Hungarian scientist Dennis Gabor first came up with the concept of a hologram while trying to improve the resolution of electron microscopes. He derived the name for holography, with "holos" being the Greek word for "whole," and "gramma" which is the term for "message." [1]
1960 – The world's first laser was developed by Russian scientists Nikolay Basov and Alexander Prokhorov, and American scientist Charles H. Townes. This was a major milestone for holography because laser technology serves as the basis of some modern day holographic displays. [1]
1962 – Yuri Denisyuk invented the white-light reflection hologram which was the first hologram that could be viewed under the light given off by an ordinary incandescent light bulb. [1]
1968 – White-light transmission holography was invented by Stephen Benton. This type of holography was unique because it was able to reproduce the entire spectrum of colors by separating the seven colors that create white light. [1]
1972 - Lloyd Cross produced the first traditional hologram by using white-light transmission holography to recreate a moving 3-dimensional image. [1]
1986 – Musician, record Producer and entrepreneur Christopher Martin Pati was the first person to theorize and propose a practical and quantitative process for plasma holography. His method involved exciting oxygen and nitrogen molecules with ultraviolet laser light (slightly above the visible light spectrum but below the x-ray spectrum) to create a plasma screen area (requiring no reflective surface, screen or special glasses) to create the holographic image. His method was registered and copyrighted with the US Register of Copyrights on January 5th, 1987. [2] [3]
1989 – MIT spatial imaging group pioneered electroholography, which uses magnetic waves and acoustic-optical sensors to portray moving pictures onto a display. [1]
2005 – The University of Texas developed the laser plasma display, which is considered the first real 3D holographic display.
2011 – DARPA announces the Urban Photonic Sand Table (UPST) project, a dynamic digital holographic tabletop display. [4]
2012 – The first holographic display is implemented in a car's interactive navigation display system. The technology was showcased through the exclusive luxury car, the Lykan HyperSport. [5]
2013 – MIT researcher Michael Bove predicts that holographic displays will enter the mass market within the next ten years, adding that we already have all the technology necessary for holographic displays. [6]
Laser plasma displays were first theorized and proposed in 1986 by Musician, Producer and Entrepeneur Christopher M. Pati. They were first developed in 2005 by the University of Texas, utilizing a series of powerful lasers that focus light in desired positions in order to create plasma excitations with the oxygen and nitrogen molecules in the air. This type of holographic display is capable of producing images in thin air, without the need for any sort of screen or external refraction media. The laser plasma display is able to depict very bright and visible objects, but it lacks in terms of resolution and picture quality.
The piston display, invented by Belgian company IMEC in 2011, utilizes a MEMS (micro-electro-mechanical system) based structure. In this type of display, thousands of microscopic pistons are able to be manipulated up and down to act as pixels, which in turn reflect light with a desired wavelength to represent an image. This developing technology is currently in the prototype phase, as IMEC is still developing the mechanism that will mobilize their "pixels" more effectively. Some of the limitations of this type of this display include the high cost, difficulty of creating large screens, and its susceptibility to mechanical failures due to the relatively large amount of moving parts (microscopic pistons). [7]
The holographic television display was created by MIT researcher Michael Bove in 2013. Dr. Bove used a Microsoft Kinect camera as a relatively effective way to capture subjects in a three-dimensional space. The image is then processed by a PC graphics card and replicated with a series of laser diodes. The produced image is fully 3-dimensional and can be viewed from all 360 degrees to gain spatial perspective. Bove claimed that this technology would be widespread by 2023, and that the technology will cost as much as today's ordinary consumer TVs. [8]
Touchable holograms were originally a Japanese invention that became further developed by American microprocessor company Intel. Touchable hologram technology is the closest modern representation of the holographic displays that one might see in sci-fi movies such as Star Wars and particularly in the Star Trek television franchise. This display is unique in that it can detect a user's touch by sensing movements in the air. The device then provides haptic feedback to the user by sending an ultrasonic air blast in return. In Intel's demonstration of this technology, the display was showcased representing a touchless, responsive piano. A possible implementation for this technology would be interactive displays in public kiosks; because this type of display does not require a user to physically touch a screen, it ensures that bacteria and viruses do not get transmitted. [9] [10]
Most modern day holograms use a laser as its light source. In this type of hologram, a laser is shone onto a scene that is then reflected onto a recording apparatus. In addition, part of the laser must shine directly onto a specific area of the display to act as a reference beam. The purpose of the reference beam is to provide the recording device with information such as background light, picture angle, and beam profile. The image is then processed to compensate for any variation in picture fidelity, and then sent to the display.
Electroholographic displays are digital displays that transmit stored image data using an electromagnetic resonator. These signals are then read by an acoustic-optic modulator and converted into a legible image and displayed on an RGB laser monitor. Electroholographic displays hold an advantage over traditional displays in terms of picture accuracy and range of color.[ citation needed ]
Full parallax holography is the process of delivering optical information in both the x and y directions. The resulting image will therefore provide the same perspective of a scene to all viewers regardless of viewing angle.
Horizontal Parallax Only (HPO) and Vertical Parallax Only (VPO) displays only deliver optical information in two dimensions. This method of display partially compromises the image in certain viewing angles, but it requires much less computational power and data transfer. Because humans' eyes are positioned side by side, HPO displays are generally preferred over VPO displays, and sometimes preferred over full parallax displays due to their lesser demand on processing power.
MEMS technology allows holographic displays to incorporate very small moving parts into its design. The prime example of a MEMS-enabled display is the piston display, listed in the above section. Micropistons used in the display can behave like pixels on a computer monitor, allowing for sharp image quality.
Mitsubishi is developing a hologram-like 'aerial display'. [11]
Holography is a technique that enables a wavefront to be recorded and later reconstructed. It is best known as a method of generating three-dimensional images, and has a wide range of other uses, including data storage, microscopy, and interferometry. In principle, it is possible to make a hologram for any type of wave.
A 3D display is a display device capable of conveying depth to the viewer. Many 3D displays are stereoscopic displays, which produce a basic 3D effect by means of stereopsis, but can cause eye strain and visual fatigue. Newer 3D displays such as holographic and light field displays produce a more realistic 3D effect by combining stereopsis and accurate focal length for the displayed content. Newer 3D displays in this manner cause less visual fatigue than classical stereoscopic displays.
A volumetric display device is a display device that forms a visual representation of an object in three physical dimensions, as opposed to the planar image of traditional screens that simulate depth through a number of different visual effects. One definition offered by pioneers in the field is that volumetric displays create 3D imagery via the emission, scattering, or relaying of illumination from well-defined regions in (x,y,z) space.
EOTECH is an American company that designs, manufactures, and markets electro-optic and night vision products and systems. The company is headquartered in Plymouth, Michigan.
Autostereoscopy is any method of displaying stereoscopic images without the use of special headgear, glasses, something that affects vision, or anything for eyes on the part of the viewer. Because headgear is not required, it is also called "glasses-free 3D" or "glassesless 3D".
The rainbow hologram is a type of hologram that was invented in 1968 by Dr. Stephen A. Benton at Polaroid Corporation. Rainbow holograms are designed to be viewed under white light illumination, rather than laser light which was required before this. The rainbow holography recording process uses a horizontal slit to eliminate vertical parallax in the output image, greatly reducing spectral blur while preserving three-dimensionality for most observers. A viewer moving up or down in front of a rainbow hologram sees changing spectral colors rather than different vertical perspectives. Because perspective effects are reproduced along one axis only, the subject will appear variously stretched or squashed when the hologram is not viewed at an optimum distance; this distortion may go unnoticed when there is not much depth, but can be severe when the distance of the subject from the plane of the hologram is very substantial. Stereopsis and horizontal motion parallax, two relatively powerful cues to depth, are preserved.
A hogel is a part of a light-field hologram, in particular a computer-generated one. It is considered a small holographic optical element or HOE and that its total effect to that of a standard hologram only that the resolution is lower and it involves a pixelated structure. An array of these elements form the complete image of a holographic recording, which is typically displayed in 3D free-viewing device.
Computer-generated holography (CGH) is a technique that uses computer algorithms to generate holograms. It involves generating holographic interference patterns. A computer-generated hologram can be displayed on a dynamic holographic display, or it can be printed onto a mask or film using lithography. When a hologram is printed onto a mask or film, it is then illuminated by a coherent light source to display the holographic images.
Stephen Anthony Benton was the inventor of the rainbow hologram and a pioneer in medical imaging and fine arts holography. Benton held 14 patents in optical physics and photography, and taught media arts and sciences at Massachusetts Institute of Technology (MIT). He was the E. Rudge ('48) and Nancy Allen Professor of Media & Sciences, and the Director for Center for Advanced Visual Studies (CAVS) at MIT.
Nicholas (Nick) John Phillips was an English physicist, notable for the development of photochemical processing techniques for the colour hologram. Holograms typically used to have low signal-to-noise ratios, and Phillips is credited as the pioneer of silver halide holographic processing techniques for producing high-quality reflection holograms.
Security holograms are labels with a hologram printed onto it for sale security reasons.
Zebra Imaging was a company that developed 3D digital holographic images, hologram imagers and interactive 3D displays for government and commercial uses. The company offers digital holograms that are autostereoscopic, full-parallax and in monochrome or full-color. They have also developed a 3D Dynamic Display, which is capable of rendering holograms in real time; design work with 3D programs such as SketchUp and 123D Catch can be viewed on a holographic display while they are actively being edited.
Digital holographic microscopy (DHM) is digital holography applied to microscopy. Digital holographic microscopy distinguishes itself from other microscopy methods by not recording the projected image of the object. Instead, the light wave front information originating from the object is digitally recorded as a hologram, from which a computer calculates the object image by using a numerical reconstruction algorithm. The image forming lens in traditional microscopy is thus replaced by a computer algorithm. Other closely related microscopy methods to digital holographic microscopy are interferometric microscopy, optical coherence tomography and diffraction phase microscopy. Common to all methods is the use of a reference wave front to obtain amplitude (intensity) and phase information. The information is recorded on a digital image sensor or by a photodetector from which an image of the object is created (reconstructed) by a computer. In traditional microscopy, which do not use a reference wave front, only intensity information is recorded and essential information about the object is lost.
Specular holography is a technique for making three dimensional imagery by controlling the motion of specular glints on a two-dimensional surface. The image is made of many specularities and has the appearance of a 3D surface-stippling made of dots of light. Unlike conventional wavefront holograms, specular holograms do not depend on wave optics, photographic media, or lasers.
Yves Gentet is a French engineer and artist, known for the invention of a creative method of holograms in colour Ultimate and a 3D holographic printer Chimera.
A holographic weapon sight or holographic diffraction sight is a non-magnifying gunsight that allows the user to look through a glass optical window and see a holographic reticle image superimposed at a distance on the field of view. The hologram of the reticle is built into the window and is illuminated by a laser diode.
Holographic optical element (HOE) is an optical component (mirror, lens, directional diffuser, etc.) that produces holographic images using principles of diffraction. HOE is most commonly used in transparent displays, 3D imaging, and certain scanning technologies. The shape and structure of the HOE is dependent on the piece of hardware it is needed for, and the coupled wave theory is a common tool used to calculate the diffraction efficiency or grating volume that helps with the design of an HOE. Early concepts of the holographic optical element can be traced back to the mid-1900s, coinciding closely with the start of holography coined by Dennis Gabor. The application of 3D visualization and displays is ultimately the end goal of the HOE; however, the cost and complexity of the device has hindered the rapid development toward full 3D visualization. The HOE is also used in the development of augmented reality(AR) by companies such as Google with Google Glass or in research universities that look to utilize HOEs to create 3D imaging without the use of eye-wear or head-wear. Furthermore, the ability of the HOE to allow for transparent displays have caught the attention of the US military in its development of better head-up displays (HUD) which is used to display crucial information for aircraft pilots.
A 3D display is multiscopic if it projects more than two images out into the world, unlike conventional 3D stereoscopy, which simulates a 3D scene by displaying only two different views of it, each visible to only one of the viewer's eyes. Multiscopic displays can represent the subject as viewed from a series of locations, and allow each image to be visible only from a range of eye locations narrower than the average human interocular distance of 63 mm. As a result, not only does each eye see a different image, but different pairs of images are seen from different viewing locations.
Holographic interference microscopy (HIM) is holographic interferometry applied for microscopy for visualization of phase micro-objects. Phase micro-objects are invisible because they do not change intensity of light, they insert only invisible phase shifts. The holographic interference microscopy distinguishes itself from other microscopy methods by using a hologram and the interference for converting invisible phase shifts into intensity changes.
Holography Art is a genre of artistic expression that leverages the scientific principles of holography, first conceptualized by physicist Dennis Gabor in 1947.