3D Displays

3D displays are displays that project images which appear 3-dimensional. Early models require the use of stereoscopic goggles, and will not be truly 3D, but some scientists expect full-fledged 3D displays to hit the market by around 2015. A primary limitation is that holograms are only designed to be viewed from one angle. Research towards making 3D displays possible focusing on head-tracking optics designed to follow a viewer's gaze from around the room, or holographic projections that can be viewed from more than one angle. Holograms and other 3D display attempts have been around for decades, but it will still be a while before we see the technology on shelves.

A company called IO2 technology has created a display called the M2i which can project full-color 3D display images in thin air, available today for about $20,000 US Dollars a unit. The display uses a rear projection system to create images in what they call "transformed air." The images look somewhat ethereal. However, the technology works in all types of lighting. The M2i display is a definite precursor to a more mature 3D display technology.

A more sophisticated 3D display was recently created by scientists at Japan's National Institute of Advanced Industrial Science and Technology. They bill the technology at the "first true 3D display," which uses overlapping laser beams to create tiny plasma flashpoints in the air, the afterglow of which is picked up by human eyes. The system generates as many as 100 airborne dots, and generates plasma "pops" at a rate of 100 times per second. Because the lasers superheat tiny portions of air to produce the plasma, the display creates a constant crackling noise, and can only produce white dots, definite impediments to commercial deployment, but an interesting approach nonetheless.

One difficulty in creating 3D displays is producing high-quality content to port to the displays. Filming a 3D image takes multiple cameras viewing from different angles, and specialized software to convert the 2D images into a 3D spatial map. The practicalities of this could hold 3D displays back for a while even after the technology becomes feasible in principle. The slow adoption rate of HDTVs is also another factor that companies will consider in choosing where to place their research and development dollars. But sooner or later, it seems that civilization will succumb to 3D display technology. What's the future without a holodeck?

3D Photography

Three-dimensional (3D) photography, or stereoscopic photography, is a method of taking photos that presents the images to the human eyes individually, mimicking what the brain does as it compiles imagery from the left and right eyes to interpret depth. There are multiple ways to capture the desired images, different ways to view the images, and a myriad of software available to enhance, process, or display the images. Three-dimensional (3D) photography can be accomplished with a single camera of any variety or with a dual-camera setup and with little to no specialized training.
Action shots are virtually impossible utilizing a single camera for 3D photography. Stationary 3D images can be created, however, by taking one exposure immediately after another with a single lens camera. Utilization of two lenses, whether accomplished with two cameras or a customized dual lens camera, is preferred so that the images can be taken as simultaneously as possible. Two cameras, ideally held together in a chassis, allow for 3D photography of moving scenes. The effect of the images can be enhanced by taking one of the pictures at a different distance or by using a downward angle.
There are a number of ways to view the images created by 3D photography. Sir David Brewster developed the first stereoscopic viewer in 1849 and displayed it at the 1851 Great Exhibition in London. Viewers and various methods of presenting stereoscopic images have evolved since then and have expanded to include digital projection and viewing on a computer screen.

The images can be presented side by side, overlapping, or alternating and are viewed with a binocular style viewer, specialized glasses, or the naked eye. The two most common naked eye viewing methods of 3D photography are cross-eyed and parallel. Other naked eye methods include lenticular and wobble, which is also referred to as wiggle. Binocular viewers allow for the display of images in stereoscopic pairs and can be found in a variety of designs.
One of the most commonly known methods of viewing 3D photography is via the use of anaglyphs. Anaglyph images are composed of two identical images presented in overlapping, or superimposed, red and blue color schemes. These images are viewed using glasses designed to converge the two color schemes to create the 3D impression. Polarization and digital projection are additional viewing methods that require specialized glasses. Viewing 3D imagery on a computer screen can be done utilizing a number of the above mentioned methods, including naked eye, anaglyphic, and polarization.

What Is a 3D Holographic Projection?

A 3D holographic projection is an image projected onto a screen that appears to be three-dimensional, which means it appears as a real object or person. Holograms were first developed on photographic film in the mid-20th century, using laser light reflected off an object. When the developed film was lit with a laser again, the image appeared as an object resembling the original. The image would change as a viewer moved around it, similar to what occurs when looking at real objects.
Later holograms were developed that could be developed using lasers, but were viewable under normal light conditions. These holograms were often used on credit cards or other documents as a security verification image, because they could not be reproduced with a standard printer. This permitted credit card companies in particular to protect themselves from forgeries by developing holographic cards.
The earliest form of 3D holographic projection was often referred to as "Pepper's Ghost". In the 1860s, a stage act by Professor Pepper used a ghostly image that appeared onstage with real actors. After a time the image would disappear, leading many to believe that a real ghost had appeared. The effect was created by a mirror effect created from clear glass.

When a lighted object is placed in front of a flat sheet of glass, the glass can act as a partial mirror, with a dimmer version of the object visible as a reflection. The "Pepper's Ghost" was created by an angled sheet of glass placed on stage between the actors and the audience. When a bright light illuminated an offstage actor, the image was reflected off the glass and toward the audience, which created a ghostly image that appeared to be present on the stage. Attempts to improve the image failed due to the limits of visibility from normal glass and light sources at the time.
In the 20th century, the development of high definition television and projectors created a new form of 3D holographic projection. The new technology used a light projector that sent still or video images through a magnifier lens and onto a thin reflective film. This technology could be broadcast onto flat or curved surfaces, and allowed people to view others in real-time for video conferencing or stage performances. The projected image is two-dimensional, but the human brain interprets the image as being three-dimensional, making an object appear real.
Another application of 3D holographic projection used laser instead of normal lighting. Standard visible light contains a wide range of light frequencies that are generated by the light bulb and travel in random directions. Laser light is a collimated beam, which means all of the light is traveling in a very narrow beam of a single light frequency. If an object is lighted with a laser, the reflected light sent to a 3D holographic projection screen is highly focused.
A focused laser beam will create a much brighter and sharper image than normal light. The image will also remain in focus if the image size or the distance from the laser projector increases. This occurs because the laser beam is not scattered by distance like normal light, and therefore will remain clear even if the image is enlarged. Applications in the early 21st century were growing in the fields of communications, stage entertainment and three-dimensional advertising.

3D Virtual Reality

3D virtual reality is a type of video game or similar computer software and hardware setup that allows someone to experience three-dimensional (3D) graphics and sounds in an all-encompassing way. This is typically created through a combination of different pieces of hardware, which can include goggles or some other type of visual display, headphones, and various input devices. Computer software then creates images for the display and can track motion and head movements to make the images respond to the motion of the wearer. 3D virtual reality can be utilized in training simulations, though developments have been made in numerous ways to try to utilize this technology in gaming.

The basic idea behind 3D virtual reality is the creation of a virtual 3D space in which a person feels immersed and that he or she can interact with in some way. This is typically achieved by having a virtual avatar for a person exist within a 3D environment, which someone can utilize through first-person perspective. The avatar then acts as the person within 3D virtual reality and moves according to the input from the user or player.

A number of different types of hardware are often used to create 3D virtual reality, beyond the computer equipment needed to run the software for this type of program. Some form of visual display is needed to allow someone to feel as though he or she is within the virtual environment. This can be anything from a series of large wall displays around a person that emulate an environment around him or her to the use of goggles or a headset with displays within them. Headsets are quite popular, as they block out other environmental factors and can include speakers to allow someone to have both visible and audible engagement with the virtual reality.

Some type of input device is also typically used with a 3D virtual reality program, to allow someone to interact with the virtual environment. Headsets can include motion detectors that change the displayed images to reflect movements by the wearer. This allows someone to look around at a virtual landscape by moving his or her head. Handheld input devices can also be used to move the virtual avatar within the space and to interact with objects in the virtual world.

The software used to create 3D virtual reality can vary quite a bit, though it usually renders out 3D landscapes and objects to create a world around the user. Training simulations, for example, can allow someone to learn to fly a plane or perform other tasks in a way that more closely resembles actual conditions. Video games have been experimenting with 3D virtual reality for some time, and continue to try to develop software that would allow for game playing within such a virtual space. Problems have existed in most of these developments, however, which have included everything from poor control and inferior graphics to headaches due to eyestrain.

What Is 3D Virtual Reality?

3D virtual reality is a type of video game or similar computer software and hardware setup that allows someone to experience three-dimensional (3D) graphics and sounds in an all-encompassing way. This is typically created through a combination of different pieces of hardware, which can include goggles or some other type of visual display, headphones, and various input devices. Computer software then creates images for the display and can track motion and head movements to make the images respond to the motion of the wearer. 3D virtual reality can be utilized in training simulations, though developments have been made in numerous ways to try to utilize this technology in gaming.

The basic idea behind 3D virtual reality is the creation of a virtual 3D space in which a person feels immersed and that he or she can interact with in some way. This is typically achieved by having a virtual avatar for a person exist within a 3D environment, which someone can utilize through first-person perspective. The avatar then acts as the person within 3D virtual reality and moves according to the input from the user or player.
A number of different types of hardware are often used to create 3D virtual reality, beyond the computer equipment needed to run the software for this type of program. Some form of visual display is needed to allow someone to feel as though he or she is within the virtual environment. This can be anything from a series of large wall displays around a person that emulate an environment around him or her to the use of goggles or a headset with displays within them. Headsets are quite popular, as they block out other environmental factors and can include speakers to allow someone to have both visible and audible engagement with the virtual reality.

Some type of input device is also typically used with a 3D virtual reality program, to allow someone to interact with the virtual environment. Headsets can include motion detectors that change the displayed images to reflect movements by the wearer. This allows someone to look around at a virtual landscape by moving his or her head. Handheld input devices can also be used to move the virtual avatar within the space and to interact with objects in the virtual world.

The software used to create 3D virtual reality can vary quite a bit, though it usually renders out 3D landscapes and objects to create a world around the user. Training simulations, for example, can allow someone to learn to fly a plane or perform other tasks in a way that more closely resembles actual conditions. Video games have been experimenting with 3D virtual reality for some time, and continue to try to develop software that would allow for game playing within such a virtual space. Problems have existed in most of these developments, however, which have included everything from poor control and inferior graphics to headaches due to eyestrain.

Holographic Display

A holographic display is a kind of three dimensional display, but unlike the three dimensional effects achieved with traditional three dimensional technologies, it incorporates a true parallax element. This means that the viewer can move around the image in any direction, and the image maintains its integrity. This technology can be used in two ways. It can be used to create a holographic image on a flat display surface that does not actually exist in three dimensions, but appears to, without any special glasses or other viewing aids. A second application is to create a virtual image in space that actually occupies three dimensions and may be viewed from any direction as though it were an actual physical object.
Flat holographic display technology is not new and has been used for decades to create the illusion of three dimensional images on flat surfaces. Like all holographic displays, such an image requires no special glasses or other special equipment to view. It appears as a three dimensional image that appears to rotate in space as the viewer's perspective changes. The most advanced versions of these displays are able to depict three-dimensional versions of aerial maps commonly found on the Internet. When laid on a surface and lighted, the objects and buildings appear to have actual substance, and the viewer can move around the perimeter of the image. Objects and images maintain their perspective regardless of the angle or direction of viewing.
New advances in technology have made possible the true three dimensional holographic display. This technology uses special rotating mirrors and laser projectors to create an image that occupies space in three dimensions, but has no physical substance. A viewer of such a display can move about the object in any direction and the object will maintain its integrity exactly as a real object would. For example, a holographic display of an apple can be viewed in exactly the same way as a real apple on a pedestal. Changing the viewing perspective in any direction will visually result in a perception of the image in exactly the same way as if it were a real object.
Research continues on both versions of this technology. In 2011, researchers at the Massachusetts Institute of Technology (MIT) have also developed an early prototype for a three dimensional holographic television display. This would incorporate existing television technologies to allow three dimensional television that exhibits true image integrity and requires no special glasses. As a viewer changes his position relative to the screen, the holographic display appears to retain its shape and depth, unlike current three dimensional television images, which quickly distort and lose their ability to accurately depict three dimensions when the viewer's perspective moves beyond a critical angle.

3D Projection

Three dimensional, or 3D, projection, which is often called 3D projection mapping, is the transference of three-dimensional data onto a two-dimensional plane. Scientists, engineers, and designers often make use of this type of mapping system when making computer or pen and paper models of three-dimensional objects. Objects may be drawn to scale or with perspective, but both qualities cannot be kept intact after translating three dimensional coordinates into two dimensions. Though 3D projection usually refers to the modeling itself, it can also refer to the projection of images that appear to be in three dimensions, such as those seen in 3D films.

By its nature, the act of transferring three dimensional information onto a two dimensional plane means that something must be lost. There are two main ways to use 3D projection, and each has its own positive and negative qualities. One way to project a three dimensional image onto a two dimensional surface is by using perspective. Perspective makes an image look to the eye as if it were three dimensional, though the sizes of the parts of that object, if measured, would not be proportionally correct. The other way to use two dimensions to represent three is to use a system called orthographic projection. In this system, the measurements are accurate but the object will not look like it has depth.

There are a number of uses for 3D projection. Engineering design and drafting both make use of three dimensional coordinate systems in the design of buildings and structures. Computer graphics also use 3D projection when modeling a three dimensional object or environment in the two dimensional space of a computer screen. Science and mathematics may also use this type of projection when modeling or graphing various natural phenomena and equations.

3D projection can also refer to the projection of two dimensional images onto a screen in such a way that they appear to the viewer to exist in three dimensions. The technology to make a two dimensional image appear to have depth has been available since the 1920s, and though there have been many improvements, the basic principles are the same. Instead of one image, two images that overlap slightly are placed on a screen at the same time. When a person is wearing special glasses, either color filters or polarized filters, each eye is only able to see one of these images, and the brain translates the information received by each eye into one three dimensional image.

What Are the Different Types of 3D Goggles?

The different types of 3D goggles include red and blue glasses, polarized lenses, shutter glasses, and personal viewers. These products require the use of a 3D image to function properly, whether a movie, television, or computer image that is designed to appear in 3D. They may be purchased at specialty electronics stores or through Internet ordering.

3D imaging works by presenting the brain with two images of the same thing taken from slightly different angles. The brain then resolves these two images into one single picture that gives the illusion of coming up off of the page, or out of a movie screen. The most commonly used form of 3D goggles which makes this technology possible are viewing glasses coded with a red lens and a blue lens. The corresponding images meant to be viewed using these goggles provide two separate pictures, one outlined in red, and the other in a contrasting color, like blue. These two differently colored pictures can be seen with the naked eye separately, however, when viewed through the color filters of the glasses which only allows one picture to enter each eye, they merge into one page-popping image.

Updated versions of these original 3D goggles use polarized lenses instead of color differentiated ones. Red and blue lenses limit the amount of color that can be transmitted through each lens, causing the filmed images to lose some of their clarity. Polarized lenses can achieve the same effect of only allowing one type of image to enter each eye, but through corresponding image polarization rather than color differentiation. These glasses are typically styled to resemble thick, plastic sun glasses, and each lens is somewhat tinted or opaque in appearance.
This image differentiation can be achieved in shutter styled 3D goggles without using image overlays. Shutter glasses are clear LED lenses which are blacked out separately from one another in a sequence. This allows each eye to see only one image at a time, allowing the brain to make the connections without risking the potential for image blurring which can occur with overlays. The sequencing is synchronized with the viewing content using a signal emitter attached to the 3D viewing device.
A personal 3D view screen may also be considered a type of 3D goggles. This headset is designed to sit over both the ears and the eyes, providing full picture and sound in high definition. Each eye lens of the goggles provides unique content, allowing the image overlay technology of 3D to be rendered for the user. These goggles may also be referred to as OLEDs, which stands for the organic light emitting diodes inside the glasses which make the pictures possible.
Once the user has placed these 3D goggles on, he may view television shows or movies in high definition or 3D privately. A virtual screen is created inside the goggles that appears to the user in a manner similar to a projection screen movie. Images may give the illusion of coming out of the screen towards the user, depending on the way in which the content was filmed. The goggles surround the head and may extend between six and eight inches (15.24 to 20.32 centimeters) beyond the face when worn.

Holographic Film

The term “holographic film” can refer to two different products. One is a special kind of packaging film used to add holographs to things like food packaging, while the other is a film designed for the production of holographic images. These two products are quite distinct, require different manufacturing processes, and tend to come from different sources because of their different end purposes. The type of film under discussion is typically clear from the context.

In the sense of packaging, holographic film is a thin sheet that may be backed by cardboard, paper, and other materials, with embedded holograms. These may be used to create more eye-catching packaging or a security measure, as a company can order custom holograms and use these to uniquely identify its products. The film is flexible, and thus can be used in flexible as well as rigid packaging and devices like small stickers or seals.

Companies may use holographic film on a variety of products. Generic lines come with basic shapes like diamonds and stars for companies that do not want or need custom holograms for their packaging. When holographic film is used as a security measure, the package may also include a description, so customers know what to look for when they evaluate the packaging or seals for authenticity. Holographic film seals are common on new electronics and software to help users avoid pirated or aftermarket products.

Another type of holographic film is a film or plate treated with a special emulsion so it can be used in the production of holograms. Several different processes can be used to make the film, and photographers may have a preference based on their experiences with different designs. A special photography setup is required to expose the film to create a three dimensional image. Projecting through the film or plate will generate a hologram suspended in air, if the photography was done correctly. Poor exposures may be blurred or otherwise degraded, spoiling the illusion.

This type of film typically comes from photographic suppliers and hobby companies that specialize in the production of holograms. It is also possible to purchase photography supplies and other accessories for making holograms. The process requires a very steady, controlled environment, without light bleeds, breezes, and other issues that are not usually an issue in conventional photography. Any disturbance during the process can push the hologram out of alignment and blur the finished image.

Spatial Light Modulator

A spatial light modulator (SLM) uses the input of an electrical or optical signal to alter light and create an image as fast as multiple times per millisecond. This can be found in many different variations and is used in a wide range of optical devices, including an overhead projector, television, or other video and graphics display. One- and two-dimensional types are available, both featuring pixels, the basic elements of any picture displayed on a screen. The many varieties of spatial light modulator can perform electrical or optical functions individually or combine them in one modulator.
Liquid crystal is often the medium used by a spatial light modulator, while a control circuit processes data into the pixel array for each frame of an image. The two-dimensional types are used in video projectors, but an SLM can also be used in many different applications. One kind, known as a Variable Electro-Optic Mirror is suited for optical systems such as beamsplitters, shutters, and mirrors. It can be utilized in highly reflective systems and manufactured on such small scales that the modulators can be integrated into windows that can lighten and darken. Micromirror devices can be built into individual chips used in scientific equipment like high-power lasers.

 Depending on the application, an SLM can work with wavelengths including near infrared. Ultraviolet and short-, mid-, or long-wave infrared wavelengths can be used to modify a specific wavelength in the light spectrum as well. A spatial light modulator is sometimes used in an effort to control the direction of laser beams, to correct the deviation of light waves, and for processing and analyzing images. It can also alter the amplitude or the phase of the light, or both if the combination of functions best suits the application.

The spatial light modulator can provide such precise control of light that engineers are considering its use in optical computing and holographic data storage. Light can be modified down to the individual pixel. The modulator and the liquid crystal element can be built on a single silicone chip for placement on circuit board components for computer video cards. Images can be transferred at very high speeds across digital video interfaces as the SLM processes dense pixel data and allows for a very high resolution display for the user. Phase rates can be as fast as less than a millisecond, so high-speed and high-quality video is made possible for all types of computers and mobile devices.

What Are the Different Types of Hologram Software?

Three-dimensional or 3D software products generally allow users to construct holograms on a personal computer. Hologram software ranges from free, downloadable programs to expensive programs. The software also varies in the methods it uses to create holograms. Some enable users to layer any photograph, creating a 3D effect. Other software programs give users the option of building images from simple shapes into multi-dimensional displays complete with animation.

Several hologram software programs allow users to create 3D imaging with animation by using photographs. One program requires users to print a guide on a piece of paper, which has various points configured in a circle. An object is placed within the circle and a photograph of the subject at various points around the circle, each portraying a different angle. Photographs are then entered into the hologram software and the program generates an animated sequence based on the different angles.

Another program uses popular photography software and allows users to choose any photograph and convert that image into a 3D hologram. The user generally dissects the photograph into separate layers — background, middle range, and forefront. The user may also cut out objects within the picture. The program then reassembles the picture layer upon layer, adding depth and, perhaps, lighting changes. Animation effects rotate the picture producing a hologram effect similar to viewing a stationary holographic picture.

Some of these programs also contain advanced tools, allowing a user to construct and animate designs using a series of complex imaging techniques. Artists have the option of choosing images within the software or creating unique objects. Much like conventional 3D modeling and rendering software, these programs begin with grayscale images viewable at variable x, y, and z angles. Users have the option of changing the object’s size, shape, color, and texture along with light angles. The software also typically has a timeline, which allows holography enthusiasts to control movement frame by frame.

Other types of hologram software that use photographs involve taking snapshots of objects, places, or people at two or more angles. The program then combines these images and creates a rotating effect, which produces a multi-dimensional hologram. The holograms produced using computer software generally recreate full color images and allow greater versatility of subject compared to traditional hologram making methods. Once created, the image files may be saved within the program or transferred to a storage device. Printing hologram images generally requires the use of complex three-dimensional printers capable of creating micron sized pixels.

What Is the Relationship Between Holography and Photography?

Early forms of holography and photography have a lot in common, as they are based on the same basic principles. Both holography and photography record images on chemically-treated film, often containing a silver halide coating. They are also both processes that utilize the reflected light from objects, and this directly affects the resolution of an image depending on how close the recording device is to the object image being captured. As well, both holography and photography equipment started out as basic and expensive technology that has become more portable with advances in microelectronics.

Three-dimensional images captured in holography utilize a laser beam that is split into two beams. One-half of the beam images the object being recorded, and this laser light reflects back to the recording film. The other half of the laser beam is channeled through a lens and reflected off of a mirror, impacting with the film and interacting with the imaging half of the laser beam in the process. This causes two versions of the image to be recorded on the film from slightly different angles simultaneously, giving the image a three-dimensional (3D) appearance when viewed from various angles. Since holograms are a unique type of double exposure, holography and photography are similar in that a holographic recorder is essentially a form of two cameras operating on one section of film.

Advances in holography and photography technologies have begun to drive the processes through which they function apart as of 2011. Digital cameras for photography no longer require the use of film, so this makes them different from holography that largely still does. Holographic images, however, are now recorded on different mediums, from specialized glasses to plastics that go beyond the standard silver halide film technique. Some modern holographic systems also utilize lasers in three colors of red, blue, and green to generate true color 3D images, and, often, these lasers must be continually on for the image to be generated off of a reflective medium.

Improvements in photographic technology have made many types of standard cameras far less expensive than early models with improved features. By contrast, advanced holographic systems that generate true color 3D images are more complex, involving multiple laser systems, and much more expensive that primitive monochromatic early hologram recorders. As hologram technology progresses, projections are that it will become more commonplace and prices will fall, though such systems are likely to lag behind the widespread use and development of digital cameras.