[ad_1]
Samsung scientists have created an interactive thin-panel holographic display that increases the viewing angle of 3D videos by 30 times.
The ultra-thin glass prototype could make it easier to integrate holographic video displays into mobile devices in the future, they say.
Holography is a photographic technique that records the light diffused by an object and presents it in three dimensions, like the hologram of Princess Leia in Star Wars.
But unlike a standard 3D image, a holographic projection allows the viewer to move around and get different perspectives from different positions.
The Korean team used their screen to view a full-screen interactive 4K video of a swimming turtle that can be seen from different angles and interacted with using a keyboard.
Scroll down the video
Researchers have developed a slim screen which means the viewing angle of 3D videos can be increased up to 30 times. Adding special backlighting and tilting light mechanism to compact hologram technology existing makes this possible in a very thin form
Commercially available holographic video displays have not yet been introduced in part due to their narrow viewing angles, bulky optics, and the high computing power required.
But the researchers, at the Samsung Advanced Institute of Technology and the University of Seoul in Korea, used a steering backlight unit, which includes a beam deflector and a holographic video processor to solve these problems.
The beam deflector, made of liquid crystals between two sheets of glass, directs the optically transmitted lights like a prism.
It uses a “diffractive waveguide” design, which controls the direction of light waves in a particular direction and saves energy.
“The directional backlight unit allows the viewing angle to be widened by 30 times and its diffractive waveguide architecture results in a slim display format,” the research team says in their paper published in Nature Communications.
Beam deflector graphic, made up of liquid crystals between two sheets of glass, directs the transmitted lights optically like a prism
Photos from the holographic video of the turtle among the corals. All the objects in the film are at different depths
“We suggest that the thin-panel holographic screen can provide lifelike three-dimensional video in office and home environments.
“The proposed system will accelerate the adoption of holographic video for mobile devices.
“Research is underway to reduce the volume of the system suitable for mobile phones.”
Holographic screens create a 3D image in space, which can be viewed next to real objects without causing eye strain.
However, compared to flat images, holographic images and especially videos are more difficult to produce and require a device with many more pixels.
Existing holographic technologies used in thin panels can only produce high resolution images when viewed directly in front of the screen, as they do not control enough pixels for more tilted viewing.
The team has developed a slim screen which means the viewing angle of 3D videos can be increased up to 30 times over existing technologies.
The addition of a special backlight and light tilt mechanism to the existing compact hologram technology makes this possible in a very slim form, which measures less than 0.3 inch (1cm) from thickness.
The prototype includes optical components (beam deflectors, coherent backlight units and a geometric phase lens), a holographic video processor board, a spatial light modulator, power connectors and other components.
Combined with a custom single-chip processor, the authors successfully displayed their full-screen interactive 4K video of a 3D swimming turtle.
The clip shows images from the holographic video with real objects such as plants, all at different depths, and the user can interact with the turtle in real time using a keyboard.
Technologies capable of producing lifelike holograms in thin panels could make 3D displays a more realistic option for use in mobile devices and home electronics.
Holographs use laser light sources, which provide a wider color gamut than LEDs common in today’s VR headsets, phones, computers, and TVs.
A common set of colors reproducible on many displays today is called the “sRGB color space” – which stands for “standard red, green, and blue.”
This figure illustrates the range of colors visible in light (outer form). The sRGB space represents a common set of colors that are reproducible on many screens today. The outer triangle represents the largest set of colors
SRGB was created by HP and Microsoft created in 1996 for use on monitors, printers, and the Internet, but it has a limited color gamut and only captures a small fraction of the colors that humans can actually see.
Holographs, on the other hand, cover a much broader set of colors, including bright light shades of the entire visible color spectrum.
Facebook is another tech company working on holographic devices – in July it revealed a concept for virtual reality lenses that are less than 9mm thick.
Wearers could have an array of bright, saturated colors when playing games or watching movies like a “brightly lit neon sign” or “the iridescent glow of a butterfly wing”.
WHAT IS A HOLOGRAM?
‘You are my only hope’: the scene from the first Star Wars movie in which a message from Princess Leia is released as a hologram for Obi-Wan Kenobi
Until now, the video hologram has generally been confined to science fiction, the most famous example being the projected image of Princess Leia in the first Star Wars movie.
Holography is light presented in what appears to be a three-dimensional form.
It is achieved by recording the light that is diffused by an object to build an image upside down.
A laser beam is split in half before half of it is directed at the object, with anything that bounces off being recorded on a recording medium, such as photographic paper.
The other half, a reference beam, is directed to the recording medium to help coordinate a clear image.
The interference between the two beams when they cross is what creates the imprint of the three-dimensional image – which is then projected for us to see.
However, existing systems which project moving holographic images are expensive and suffer from severe limitations.
The main problem is with devices called spatial light modulators, which direct light to form points in three-dimensional space.
With current technology, the key elements of display size, viewing angle, frame rate, and image depth are limited.
Current hologram technology is static, with moving images only obtained by strobing images together.
A solution could be found in the form of acoustic levitation, as developed by researchers at the University of Sussex.
[ad_2]
Source link