The first hologram was obtained by the Hungarian physicist Denesh Gabor in 1947 during experiments to increase the resolution of electron microscopes. He coined the very word "hologram", wanting to emphasize complete record optical properties of the object. Denesh was a little ahead of his time: his holograms were of poor quality due to the use of gas discharge lamps. After the invention of ruby-red and helium-neon lasers in 1960, holography began to develop rapidly. In 1968, the Soviet scientist Yuri Nikolaevich Denisyuk developed a scheme for recording holograms on transparent photographic plates and obtained high-quality holograms. And 11 years later, Lloyd Cross created a multiplex hologram consisting of several dozen angles, each of which can be seen from only one angle. How does modern holographic display- about it in today's issue!
The main photographic material for recording holograms are special photographic plates based on traditional silver bromide, which make it possible to achieve a resolution of more than 5,000 lines per millimeter. Also used are photographic plates based on bichromated gelatin, which have a higher resolution. When used, up to 90% of the incident light is converted into an image, which makes it possible to record very bright holograms. Media based on holographic photopolymer materials are also being actively developed. This multicomponent mixture of organic substances is applied as a thin film on a glass or film substrate.
HoloVisio brand displays from the Hungarian company Holografika already exist on the market. The essence of their technology lies in the projection of the picture by two dozen narrowly focused projectors, due to which the image is laid out in space deep into the display. The complexity of this technology affects the price: the cost of a 72-inch screen with a resolution of 1280 by 768 pixels is about 500 thousand dollars.
It is quite possible that in the near future holographic screens will become more accessible and widely used.
Plasma panels and LCD screens have not surprised anyone for a long time, having taken their place in everyday life. The technology of creating a stereoscopic image using 3D glasses, which has taken its niche and is actively developing, has become familiar in recent years. Most experts are of the opinion that the next stage in the development of display technologies will be the appearance of a holographic projection screen, which is quite logical, since modern 3D television is an intermediate stage in the formation of a three-dimensional image, since a three-dimensional image on such screens is visible only at a certain position of the head. Holographic displays can be seen as the next step in the development of 3D technologies.
Modern cinemas and TV use 3D technology, which is based on deceiving the human eye by presenting slightly different images to the eyes, which ultimately creates a three-dimensional effect. Optical focus is widely used in 3D technology: for example, the illusion of depth and volume of an image is created using polarized glasses that filter part of the image for the left and right eyes.
The disadvantage of this technology is that the three-dimensional image is visible only at a certain angle. Despite the fact that home TVs with 3D effect and without glasses are on sale, the viewer can watch them only if he is exactly opposite the display. The three-dimensional image begins to disappear when slightly shifted to the right or left relative to the center of the screen, which is the main drawback of all 3D displays. Holographic screens should solve this problem in the near future.
Today, pseudo-holographic screens based on a translucent grid or film are very popular. Panels are attached to the ceiling or shop window. With proper lighting, the panels are invisible to humans, and if an image is projected onto them, it creates the impression of a hologram through which the viewer can look. In comparison with plasma, pseudo-holographic screens have a number of advantages: a bright image, originality, and the ability to install in any room.
The projector that projects the image may be hidden from the viewer. The advantages of such equipment are wide viewing angles, high image contrast and the ability to create holographic screens of a certain size and shape. Displays on translucent film are used to give an unusual effect and charm to the room, decoration of television studios and retail spaces. Transparent panels are produced by many companies and are used for advertising and marketing purposes.
One of the most popular are Sax3D holographic screens from a German company, created using selective light refraction technology, due to which the system ignores any light in the room, with the exception of the projector beam. The display itself is made of durable transparent glass, on top of which a thin film is applied, turning the screen into a hologram and displaying the contrast image projected by the projector. Such a holographic screen allows you to view both digital images and videos. Transscreen displays work on a similar principle, created from a polyester film with special layers that delay the light coming from the side of the projector.
Residents are more interested not in specialized screens, but in solutions that can be used in tablet computers, TVs and smartphones with a holographic screen. It should be noted that in this area in recent years there has appeared a large number of original solutions, despite the fact that most of them work on an improved 3D effect.
InnoVision at CES 2011 presented to the public a prototype TV with a holographic screen called HoloAd Diamond. When creating a TV, a prism is used that refracts the light coming from several projectors and creates a full-fledged hologram that the viewer can view from different angles. During the demonstration, visitors to the exhibition and journalists were able to make sure that such a hologram significantly exceeds the images created by classic 3D devices in terms of color saturation and depth.
HoloAd TV can play FLV images, photos, and videos as a hologram. At the exhibition, the company presented two TV models based on a similar principle: the resolution of the first is 1280x1024 pixels, the weight is 95 kilograms, the resolution of the second is 640x480 pixels. Despite the fact that the TVs are quite large, they are convenient and comfortable to use.
HP's Palo Alto labs have attempted to fix the age-old problem with 3D screens. To reproduce a three-dimensional image visible from any point of view, the researchers proposed to show the image from different sides, sending for each eye of the viewer a separate picture. This technology involves the use of a system with laser systems and rotating mirrors, however, Californian scientists resorted to the components of a conventional liquid crystal panel, inflicting a large number of round grooves on the inner surface of the screen glass. As a result, this made it possible to refract light in such a way as to create a three-dimensional hologram in front of the viewer. The screen, created by HP specialists, shows viewers a static three-dimensional image projected from two hundred points, and a dynamic picture from sixty-four.
Relatively recently, the event expected by many finally took place - a smartphone with a holographic display was officially presented. Used in Red phone Hydrogen One display technology is expensive, but will be used on many mobile devices in the near future.
Red primarily specializes in the production of professional digital cinema cameras, but now it has turned its attention to a new industry with the development and introduction of the Red Hydrogen One holographic smartphone.
Red said that the screen installed on the smartphone is a hydrogen holographic display that allows you to instantly switch between 2D content, 3D content and the holographic content of the Red Hydrogen 4-View application. Despite the fact that exact information about the principle of this technology has not been published, the smartphone allows you to view all the holograms without the use of special glasses or additional accessories.
Demonstration Smartphone Red with a holographic screen was held in June 2017, but no details have yet been disclosed by the manufacturer. However, there are a few lucky bloggers who managed to hold two smartphone prototypes in their hands: one is a non-functional mock-up showing the finish and appearance phone, the second is a working device, which the company still keeps secret.
The German company SAX3D was founded in 1998. The development center is located in Chemnitz. In the manufacture of holographic optical elements, SAX3D uses a patented system selective refraction of the light flux, which allows you to ignore any light in the room, except for the beam of the projector. This technology formed the basis for the development of SAX3D holographic screens.
SAX3D screens are an excellent alternative to the usual display tools that carry an advertising or informational function. The manufacturing technology of these screens was developed several years ago by German engineers from Sax3d GmbH with the sole purpose of attract the attention of the audience and the screens have already been found in this capacity wide application in European countries.
Sax3d is technically a projection screen that almost completely transparent(its base is made of durable glass) and at the same time displays a bright and contrasting image created on it by a conventional projector. Himself behind the screen, thanks to which the audience does not notice him, and the main intrigue is created: how does the image appear, because there are no wires going to the screen!
The content for the screen can be a regular video clip or a selection of photos running on a computer connected to the projector. At the same time, the only wish for the displayed materials is their location on a black background, which will further emphasize the transparency of the screen.
Currently, no major office, shopping mall or an event is not complete without plasma panels or LCD monitors. They have become such a common and integral element that one might be surprised by their absence rather than their presence. In this regard, many companies are looking for new means of attracting the attention of customers and technological equipment.
Glass holographic screens have become an ideal solution for such tasks. Transparent screens can be hung from the ceiling, fixed to the floor, or fixed directly to the glass of a shop window (the projection film is only a few millimeters thick).
The translucent picture attracts the eye, and the screen itself does not disturb the space, as it allows you to look through the image. Holographic screens allow you to give the room a special charm, create a unique image and attract the attention of potential customers.
The image is projected onto transparent holographic film, which is printed on the surface of the screen. In addition, the film can be applied to almost any transparent surface - for example, to a shop window.
The film size allows for seamless application on screens up to 60".
The image is projected at an angle of 20, 38 or 55 degrees, which allows you to hide the projector from the eyes of the observer based on the characteristics of the room.
Unlike standard projection solutions that require screen space dimming, when using screens Sax3d The strength of ambient light has little to no effect on image quality. This is possible due to the fact that the holographic film transmits only the light of the projector beam, ignoring other light fluxes coming from other angles.
The holographic screen can be used as interactive panel. This is achieved thanks to an additional touch layer.
SAX3D holographic screens can be represented both as a standard pseudo-holography and as a holographic touch screen. Each solution has its own technical features and intended for various purposes. The manufacturer distinguishes three main groups of SAX3D screens:
SAX3D Glass (glass)- a finished screen with a glass base. It can be suspended with a thin metal cable in the interior of the room.
SAX3D Touch Glass- an analogue of Sax3d Glass, equipped with an additional touch layer that provides the "Touch" function - feedback finger touches. With the help of interactive coverage, information will become tangible and “alive”, which will make an indelible impression on those present.
SAX3D Foil (film)- the film screen intended for drawing on the transparent bases, including show-windows of shops. Interactive holographic film SAX3D - Touch Foil is able to turn an ordinary storefront into an outstanding marketing tool that attracts the attention of passers-by.
Optical circuits are necessary for the correct positioning of the projector relative to the screen, which is critical when creating an installation based on the Sax3d screen. The internal structure of the Sax3d screen fabric is designed to refract and scatter the light flux directed from a strictly defined angle.
The placement of the screen and projector in accordance with the optical design ensures that the audience will see the highest quality image.
We are already accustomed to plasma panels and LCD screens in everyday life. No one is surprised by such a display technology that has appeared in recent years as 3D. The technology for creating a stereoscopic image using special 3D glasses has successfully occupied its niche and is actively developing. Many experts believe that further development display technology, or rather, a real revolution in this segment will occur with the release of holographic screens. Indeed, in fact, modern 3D television is an intermediate stage on the way to creating a real three-dimensional image, since such screens look three-dimensional only at a certain position of the head. Holographic displays in this regard can be considered as a further development of 3D technology.
The basic principle behind the 3D technology used in today's TV or cinemas is to trick the human eye into seeing it as 3D by presenting slightly different pictures to each eye. This optical focus is ubiquitous in today's popular 3D solutions. For example, the illusion of volume and depth of the picture is created using polarized glasses that filter part of the image for the right and left eyes.
But this technology has a significant drawback - a three-dimensional picture is visible to the viewer only at a strictly defined angle. Today, home 3D TVs without glasses have already appeared on mass sale. But even when watching such a TV, the viewer must be exactly opposite the screen. It is enough to move a little to the right or to the left of the center of the screen, and the three-dimensional picture is already starting to disappear. This is a shortcoming of modern 3D screens in the near future, the so-called holographic displays will have to solve.
We all remember scenes from famous Hollywood films like Star Wars, where a three-dimensional image appears in the form of holograms and literally hangs in the air. A hologram is, in principle, a special type of three-dimensional projected image that can be created using laser light or other sources. It is believed that in the near future this technology will step into our daily lives. True, so far the release of holographic TVs is still very far away. From time to time, interesting prototypes of devices with pseudo-holographic or advanced stereoscopic displays appear, which are of great interest to the public. But there are no full-fledged holographic screens available for sale yet.
For example, the so-called pseudo-holographic screens based on the use of a special translucent film or mesh have already found wide application today. Such panels are simply suspended from the ceiling, or fixed on the glass of the shop window. With special lighting, the translucent panel becomes invisible to humans. And if an image is projected onto it, then it creates the impression of a picture reigning in the air - that same hologram. The image is projected onto a translucent panel using a projector. The panel allows the viewer to see through the picture. Such pseudo-holographic displays have a number of advantages over plasma or LCD screens due to their originality, juicy image in almost any lighting conditions and the possibility of placement at any point.
The projector itself, projecting the image, may remain out of the view of the viewer. The undoubted advantages of such solutions also include good viewing angles (close to 180 degrees), high contrast pictures and the ability to create holographic screens of large size or a certain geometric shape. Naturally, displays on a translucent film are used primarily to give the premises a certain charm and unusual effect, decoration of retail spaces and television studios. Transparent panel solutions are being developed by many companies and are primarily used for marketing and advertising purposes to impress consumers.
ist. visionoptics.de In particular, film-based Sax3D screens have become widespread. This German company uses a system of selective light refraction, which makes it possible to ignore any light in the room, except for the beam of the projector. The main screen itself is a durable glass, completely transparent. It is on it that a special film is applied, thanks to which the screen turns into a kind of hologram and displays a contrasting image projected by the projector. You can view videos and digital images on such a pseudo-holographic screen. Approximately according to the same principle, Transscreen screens work, based on the use of polyester film with special layers that can delay the light coming from the projector.
But we, of course, are primarily interested in solutions that can be used in TVs, tablet computers and smartphones. And it should be noted that in recent years there have been more and more interesting devices in this area, although most of them actually use the same notorious 3D effect, only slightly supplemented and improved.
At CES 2011, InnoVision Labs demonstrated to the public a prototype TV of the future - TV with a holographic screen. The development was called HoloAd Diamond. It is a prism that can refract light coming from multiple projectors, creating a complete hologram that the viewer can view from any angle. Moreover, journalists and ordinary visitors of the exhibition were convinced that the hologram created by HoloAd Diamond looks better in comparison with 3D images on 3D devices. Pictures on the holographic screen are distinguished by depth and rich colors.
This projector-TV can reproduce in a hologram not only photos and pictures, but also videos, however, so far only in FLV format. At the exhibition, two models of TVs based on the same principle were demonstrated at once. The first supports a resolution of 1280 x 1024 pixels and weighs 95 kilograms, while the second TV is more compact, but only has a resolution of 640 x 480 pixels. The devices are quite bulky, but they are convenient to use. The older version of the holographic screen can be purchased for ten thousand dollars.
Researchers at HP's California lab in Palo Alto have tried their own way to solve the age-old problem of 3D screens. In order to reproduce a three-dimensional image that would be visible regardless of the viewing angle, the researchers proposed to demonstrate the image of objects from different sides, while simultaneously sending a picture to each eye. This is usually achieved through the use of a whole system with rotating mirrors and laser devices. But the California scientists took the components of a standard LCD panel, applied a huge number of round grooves to the inner glass of the screen in a special way. As a result, the light is refracted in such a way that allows the viewer to see a three-dimensional hologram. In any case, the screen created by HP researchers allows a person to see a static three-dimensional image from two hundred different points, and a dynamic 3D image from sixty-four. True, the scientists themselves note that the creation of a full-fledged moving hologram, which we see in the cinema, is still far away.
An interesting solution is offered by Microsoft Research, which developed the Vermeer display. This screen creates a holographic image, "floating" right in the air in the spirit of the legendary "Star Wars". It uses the effect of an optical illusion, called the "mirascope". Structurally Vermeer consists of two parabolic mirrors and a projector with a special optical system capable of reproducing up to three thousand pictures per second. The projector projects a 192 dot hologram at 15 frames per second.
Most importantly, the 3D view is available from any angle (360 degrees). Moreover, the user can successfully interact with this kind of hologram, since access to it is not blocked by any glass panel. That is, it can respond to touch. To do this, the device provides for the presence of infrared illumination and a camera, the main purpose of which is to track the movements of a person's hands.
The Vermeer display has not yet been commercially launched, but it is clear that it does have serious prospects, for example, in the gaming industry. This innovative device appeared in 2011, and a year later Apple company patented its own display, which in many ways resembles the same Vermeer. It is an interactive screen that can display 3D holograms and allow the user to interact with them.
The same pair of parabolic mirrors are used here. But there is also a difference. To project a three-dimensional picture, Apple engineers suggest using not a real object, but a substance with a photorefractive effect. The infrared radiation falling on it passes into the visible spectrum, forming a primary three-dimensional image. The device, created by Apple engineers, supports gesture control thanks to the built-in sensor system.
And this year, a long-awaited event took place - the world's first smartphone with a holographic display was presented. In any case, this is stated by its manufacturer. The Takee phone was developed by Shenzhen Estar Technology, a Chinese R&D company. But the development is actually very similar to the Amazon Fire Phone model released earlier, which offered the ability to adapt the picture on the screen depending on the user's angle of view. However, according to the manufacturer, they have gone a little further in their smartphone. It uses sensors to track the position of the eyes, located above the screen. A stereoscopic image is created by projecting external sensors directly onto the retina of the viewer's eyes, while the latter can deviate his gaze from the screen and still see a three-dimensional image.
Thus, the Takee smartphone screen makes it possible not only to see a three-dimensional image, but also to view it from different angles. In fairness, it should be noted that the Chinese development is just ordinary 3D technology, supplemented by eye tracking sensors. The display supports a resolution of 1920 x 1080 pixels. In addition to the screen, the innovative smartphone has the following features − Mediatek processor 6592T, two gigabytes random access memory and 13 megapixel camera Sony Exmor RS. The device is running Android OS. Several smartphone applications are already available that allow you to play 3D games.
Obviously, the long-awaited moment is approaching when we will be able to see TVs, tablets and monitors that create a full-fledged holographic picture. In addition, in the near future, holographic screen technology may find application in navigation systems, business industry and education. Also, holographic images simply cannot pass by the field of gaming entertainment, providing the creation of voluminous, virtual worlds with an extremely realistic picture.
