A volumetric display is a display system that form an image of an object in all three real dimensions, rather than the flat surface image of flat screens that simulate true depth through many different graphical effects. These types of displays use one or more curved screen units in order to achieve the optical illusion of three-dimensional viewing. Curved screens are typically made using a flexible substrate with holes. The viewing angle of these devices can be adjusted, giving you the ability to view a scene from any direction you desire. Because these devices do not utilize a monolithic screen substrate like LCD screens, they do not require the use of backlighting systems to add light to your image.
Another advantage to these displays is the flexibility in which they can be set up. There are two ways to design these displays - either using a full array of curved units, or the simpler method of mounting multiple flat panels on a glass or metallic frame. Mounting with a glass or metallic frame allows for a more intricate design, while allowing the light from the curved panels to shine through the glass to make the entire image brighter. Some of these devices are also available with a full array of polarised lenses. This provides even more precision in the image produced.
Types of Volumetric Display
The other main type of volumetric display is comprised of a thin film transistor liquid crystal display (TVFLD). In this case, the image is produced by passing a pulse through a series of positively charged electrodes. The light emitted is combined with the charge separation between the positive and negatively charged electrodes.
The advantages of using this type of volumetric display are the ease in which the image can be viewed. They offer a greater level of detail than their curved counterparts, and there is greater freedom of movement, due to the lack of a rigid substrate. You can move the pixels around quite freely, resulting in a much clearer image. The drawbacks are that the motion blur can be significant, and it's common for some lamps to burn out. Also, the volume of light emitted is typically lower than with flat panels.
A volumetric display can be made from a wide variety of materials. Glass and metals have been used for years, although coloured televisions use dyes. TFT (Thin Film Transistor) technology was first developed in 1980. The development of this particular technology has had a huge impact on the cost of LCD and plasma TVs. TFTs are expensive because they require an extremely clean, smooth surface - a trait not all manufacturers have. Additionally, the heat dissipation isn't as efficient with TFTs as it is with LCDs.
Volumetric displays can also be made from flexible substrates. This gives the manufacturer greater control over the quality of the display. It is also possible to utilise different material through the same panel, meaning you can create a much thinner, more efficient display if needed. Plastic, for example, is widely used for this type of display.
Flat panels are also becoming more popular as smaller, more mobile devices. Portable DVD players have been popularised by portable LCD monitors. Phablets are another device that is making a big debut this year. These are slim handheld phones that feature mobile applications and display touch screens. They are designed to work as a stylus rather than a desktop PC.
Volumetric displays are available for a wide range of purposes. These include large outdoor screens, interactive walls and even illuminated signs. They can also be created using a variety of technologies, including by printing directly onto a substrate. This offers greater control over the quality of the display and also gives the designer more flexibility.