I was looking at the proposed Calicut Airport land acquisition plan for expansion. An additional 385 acres of land would be required for providing RESA and Safety Area . What surprised me was the 18 acre which was proposed for installation of runway approach lights , 900m in length. Isn’t that too much to ask for, I wondered? A new terminal building with a bigger apron would help movement of increased number of aircraft and passengers, thus improved revenues for the airport dogged by a table top runway which doesn’t fully comply with DGCA & ICAO requirements. The Air India express accident in August 2020 set the ball rolling and grabbed the attention of the politico’s for providing a safer operating environment and infrastructure.

What if we had lights which were virtual and 3 Dimensional I wondered?

Virtual lights

My next thoughts turned towards the need to develop an approach lighting system that doesn’t require all that land, frankly speaking looks like a wasted activity. The buzz in my mind was to develop an airfield lighting system which doesn’t need all the infrastructure to house it. All the metal holdings and lengthy wiring systems. I looked at lasers but they had their drawback of pointing is a particular direction. I needed something that cuts through the air and is visible even during adverse weather like fog and rains and also which is three dimensional. What if the entire airfield can be lit up with one switch and its 3D virtual.

Volumetric imaging

Projecting an object in a 3D format is a fantasy we all share. From the likes of Star Wars to Black Panther, we have seen numerous sci-fi movies use the concept of ‘volumetric display’ to present 3D information in real 3D space. But now, researchers have proved that we are close to achieving this concept into an everyday reality. According to a study published in Nature in 2018, a team of scientists have figured out how to manipulate nearly unseen specks in the air and use them to create 3D images that are more realistic and clearer than holograms. The study’s lead author, Daniel Smalley, a physicist at Brigham Young University in Provo, Utah and his team had created a small butterfly appearing to dance above a finger and an image of a graduate student imitating Leia in the Star Wars scene.

Referred to as “optical trap display” the technology uses forces conveyed by a set of near-invisible laser beams to trap a single particle — of a plant fiber called cellulose and heat it evenly. That allowed the team to push and pull the cellulose around. Then the second set of lasers project visible light (red, green and blue) onto the particle, illuminating it as it moves through space. Humans cannot discern images at rates faster than 10 per second, so if the particle is moved fast enough, its trajectory appeared as a solid line, like a sparkler in the dark.

In simple terms it is a 3D printing of light. It’s best to watch a video to get the feel of reality with volumetric imaging.

Advantages

Accommodation. Human eyes accommodate to volumetric image points just as they do to actual material objects, because volumetric image points are material objects—at least for a brief moment. However, ray and wave displays form optical real image points by the convergence of light. The quality of that point, or point spread function, depends strongly on the size and quality of the aperture that supports it. Is it coherent? Does it present a large numerical aperture? To match the accommodation of a volumetric point, a ray or wave display would have to completely surround the point, converging from all directions to form the image. Only then could the display aperture be prevented from degrading the accommodative effect.

View angle. The supremacy of volumetric displays also shows in their large view angle, which generally comes “for free” in volumetric displays. Wide view angle in ray displays and especially in holographic wave displays, in contrast, comes at the price of tremendous hardware and computational complexity.

Occlusion. On the other side of the ledger, occlusion—the ability of one object in a 3-D scene to partly obscure another—presents a considerable challenge for point/volumetric images. In general, the image point primitive wants to emit isotropically, but to create images with self-occlusion, it must be possible to turn off the point’s emission in some directions. In ray and wave displays, achieving occlusion is a much simpler matter that generally boils down to careful content creation.

Virtual-image formation. A virtual image can be thought of as a window into another world, which may have no mapping on reality, and it likewise presents challenges for volumetric displays. If a display is hanging on a solid brick wall, but the 3-D image shows an open landscape in the background, it may be necessary to create wave fronts or rays that back-cast to points that cannot exist in real space. Given the requirement that volumetric displays have physical scatterers or emitters co-located with image points, virtual images would seem to be fundamentally impossible for volumetric displays.

An array of tiny emitters that acts like a phased array, or even like Huygens sources, might be made to create virtual image points. But such a display would create an aperture (the array boundaries) that would limit the viewable angles of the virtual image point. It would cease to be a volumetric display and instead become a phased-array wave display formed with volumetric hardware. It would thus inherit the affordances, and challenges, of the wave display family at the expense of the advantages of the volumetric-display family.

Source:

Volumetric Displays: Turning 3-D Inside-OutDaniel Smalley, Ting-Chung Poon, Hongyue Gao, Joshua Kvavle and Kamran Qaderi

Volumetric imaging is an upgrade from VR displays. Also, neither does it require any headset like AR-VR. Further, these volumetric displays can work on any 3D input device like Kinect, Leap Motion, and Structure. Speaking about applications, one can use the volumetric display for 3D Human Size communications like in Sci-fi movies where humans appear in projected forms for a top-secret mission. Like the medical and healthcare industry use this display for a number of use cases, including surgical planning, post-op review, training, doctor-patient communication, and diagnosis, aviation can use it for training and operations.

• Airfield lighting
• Virtual marshaller
• Engineering trouble shooting
• Customer service
• Crew training, virtual flight deck or Cabin
• plethora of uses in aviation.

At present, the major companies present in this market include 3DIcon Corporation (US, LightSpace Technologies Inc. (US), Voxon (US), Holografika Kft. (Hungary), Zebra Imaging (US). VOLUMETRIC DISPLAYS: TRANSFORMING THE WORLD OF IMMERSIVE TECHNOLOGIES by PreetiPadma

Welcome to the SciFi world with mindFly