Let's look at the digital hologram!

Let's find out about the principles of holograms

Holograms refer to holographic images, and holography refers to the technique of recording and playback of stereoscopic information using the interference of light caused by two laser beams meeting each other. Holograms are largely divided into analog and digital methods, and there are similar methods that mimic holographic image effects, such as super duplex stereoscopic images. Unlike analog holograms, which record two light interference patterns on film, digital holograms use electronic devices and photoelectric devices to implement holographic images and process graphic data alone through optical processing.

Since most of the hologram technologies currently being used are analog holograms or applied the technical principles of holograms, it is expected that more than 10 years will be required for fullscale commercialization, since the technology is still being developed worldwide. Network infrastructure is ready for real-time high-speed, high-capacity data transmission with 5G commercialization, and related markets are expected to continue to grow in the future as digital hologram-related research is conducted worldwide due to various application possibilities. The global hologram market is expected to continue to grow at an annual average rate of 6.8% and reach about $18.3 billion by 2022.

What are the key technologies and issues of digital holograms?

Computer Generated Hologram (CGH) technology for digital holograms is considered a major issue with the technology for digitally simulating the progression of light waves to synthesize holographic images, and it is now possible to address a variety of virtual scenes that are difficult to produce in a reality-based hologram. In addition, holographic compression techniques can be divided into two ways: compressing the hologram itself greatly and compressing the information on the diffracted side at that location after propagating the hologram to a specific distance. And holographic playback has long been reproduced only in the form of photo-like still images, but with the recent advances in 5G communication and ultra-high resolution display technology, video playback has improved to a level that is possible.

Although holograms are already familiar to people, the market still utilizes 2D digital displays or similar holographic displays, and technology levels are still in the early stages of research, which requires active investment from each country in order to take advantage of challenging R&D for technology initiatives. To lead the future real-life media industry, we need to secure technological competitiveness early by investing in hologram R&D, which is a key technology and developing original technologies. First, it is necessary to develop technologies for acquiring and processing light fields and digital holograms using multiple camera arrays and structural lights for creating holographic images. And with long-term R&D investments in super-high compression coding technologies for holographic data, we need to overcome the compression and delay limitations of existing technologies and gain a future source technology advantage. In addition, spatial variation (SLM) technology reproducing holograms is very low in viewing angle and quality, so much technology development is still required for practical services. We need to prepare a foundation for the spread of holographic content services, and in the short term, we need to develop various technologies to address cognitive side effects such as motion sickness, which is the fundamental problem of realistic content. We need to strengthen the technology development of core components and materials for implementing digital holograms, and also need an industry activation policy so that various real-world display and content producers can participate. We need to integrate holograms into existing industries such as health care, education, automobiles, security, and energy to find them as high value-added business models or promote development to improve global competitiveness and promote industrial revitalization.

The Reality of holograms in Realistic Media

The need for holographic technology, which provides a complete three-dimensional feel in a virtual space, is growing in the era of 5G communications, represented by super-fast and ultra-low delays. In particular, because more than 70 percent of the information given to users is based on vision, the need for full stereoscopic images is increasing. holographic technology is a key technology that drives the advent of an ultra-realistic era because it contributes to providing ultra-realistic content services in various fields in the 5G era beyond virtual reality (VR) and augmented reality (AR). The hologram is the ultimate stereoscopic image that records all the information on the subject and reproduces the three-dimensional shape based on the viewing angle, providing a natural three-dimensional feel to the observer. Therefore, holograms are the ultimate technology that can provide users with continuous depth and a three-dimensional feel, but they are still in the early stages of technology development due to their high technical difficulty. In order to implement a hologram as a three-dimensional image, we need to record and implement all the information on the subject, so there's a lot of data that we need to process, and there's still a limit to commercialization. Today's digital holographic technology has a very limited viewing angle and a lower picture quality than the analog hologram, allowing you to see a single point of the video the size of a fingernail. Real holograms require shooting images with more than 240 laser beams at 360 degrees, but they are not really feasible due to limitations in optical technology, interference in light, and the sheer volume of data. The holographic technology currently used in performances or exhibitions is a floating technology that shoots images into a high-resolution projector and projects them into a two-dimensional, large transparent membrane so that the images that can be seen cannot be a truly real hologram.

On the industrial front, holograms are expected to have significant ripple effects in various fields, including broadcasting, education, medical care, and manufacturing. While the need for a new growth engine industry to drive the future economy is emerging, holographic technology to realize the hologram is expected to be a new growth engine for the future economy. In fact, Gartner selected immersion experience as a promising technology in 2019 as one of the top 10 strategic technology trends. Since true holograms can display images in real space without HMD or special glasses, they are expected to bring about a paradigm shift across industries such as the entertainment sector. Analog holograms are currently used as security certification tools, but they are expected to generate high-value value through various applications in the fields of packaging, clothing, photography, and publishing. Digital holograms are expected to create new value in cultural, artistic, broadcasting, education, medical, manufacturing, etc. Digital holographic technology is in its early stages around the world, and actual commercialization requires technological development to implement holographic three-dimensional images with wide viewing angles and screens. We need thousands of Super HD spatial light transducers to get a 50-inch holographic display. Given that holograms are defined as next-generation video and industrial technologies in the U.S., Japan, and Europe, and that we are developing technologies at the national level, we will be able to develop them into expected industries.