Inside the Holographic Projection Research Institute.
Huang Junjie was currently testing the holographic projection chip with a large group of researchers.
There are currently three known holographic projection technologies in the world, namely 36° holographic display technology, air projection technology, and laser beam projection technology.
Among them, the 36° holographic display technology is the easiest to understand. It projects the image onto a mirror and then allows the mirror to rotate at a high speed to produce a 3D stereoscopic image.
Air projection technology uses water vapor to project images on the water vapor. Due to the uneven vibration between molecules, a three-dimensional image can be formed.
Laser beam projection technology is the most complex. It uses nitrogen and oxygen to disperse in the air. The mixed gas turns into a hot slurry and projects a 3D image in the air. However, this technology displays the time Very short.
Galaxy Technology's holographic projection chip is an advanced version of laser beam projection technology.
At present, when talking about holographic projection, the commercial scenario that comes to mind the most is virtual idol concerts, such as Hatsune Miku and Luo Tianyi.
But unfortunately, they are all pseudo-holographic projections and not true holographic projections.
Although the virtual idol concert presents a lifelike three-dimensional image to the audience, it must be on a fixed stage and in the dark, and the audience must watch it from a specific angle.
So how is a virtual idol concert implemented?
It actually belongs to an optical illusion technology, which we call Pepper's illusion, and is often used in magic performances.
Its principle is not complicated. It uses a semi-transparent and semi-reflective film, which is the so-called transparent holographic film, as a medium to make the object become a virtual image in the film. Because it is semi-transparent, you can see it The scenery behind the film visually gives people a three-dimensional illusion.
Coupled with CG technology (computer graphics technology) and high-brightness lights, this three-dimensional image will give the audience a vivid and realistic feeling.
Most of the so-called holographic projection technologies we see on the market are pseudo-holographic projection technologies based on Pepper's illusion.
The holographic projection realized by this technology has very obvious advantages and disadvantages.
The advantage is that the technical principle is simple and easy to implement; the disadvantage is that it cannot achieve 36oc. The audience must be in a relatively dark environment and from a specific angle to see the three-dimensional image. In addition, most projectors must be fixed and adjusted.
As for the real holographic projection technology, it is still lying in the laboratory.
The holographic projection chip designed by Huang Haojie is to produce three primary color lasers on a silicon wafer.
These three primary color lasers are very tiny. How small are they?
Each laser is the size of a square with a side length of 2 nanometers. Adding the spacing between lasers, a laser needs to occupy an area of 16 square nanometers.
On 1 square centimeter of silicon wafer, 625 million three primary color lasers need to be integrated.
The three-primary color laser can be said to be the core technology of Huang Haojie's holographic projection chip.
A popular saying in the laser industry is that as long as a green laser is added, the final performance and effect of the white light source system will be almost completely determined by it.
This applies not only to laser light sources, but also to Led light sources.
In fact, the high-brightness LED projection cannot be popularized, the complex structure of the two-color laser, the mixed light source of LED and laser, etc. The key to these matters are all green optical devices.
For laser projection, the current performance of green lasers is usable, with low light output power (less than half that of red and blue laser semiconductors), lower light efficiency (less than half that of red and blue laser semiconductors), and temperature sensitivity (light efficiency and lifespan increase with temperature).
High and fall faster) to describe the three core bottlenecks.
For Led projection, under the background that red and blue Led devices are almost 70 to 80% cheaper than similar laser devices of the same brightness, the reason why Led light source projection has not been able to get out of its infancy lies in the performance of green Led devices.
The core bottlenecks of green Led are basically the same as laser green light sources, which are also the three major problems of "low light output power, lower light efficiency, and temperature sensitivity".
For example, the brightness of the LED light source changes only 10% at 2° and 12°, while the brightness of the green LED changes by 40%. This causes the color of the white light system with green LED to shift during temperature changes.
At present, developing high-efficiency green lasers or Led light sources has become the core task of the semiconductor light source industry.
In fact, whether the future of projection is Led light source or laser light source will largely depend on which technology breaks through the green bottleneck first.
The green bottleneck is not only a problem with projection technology, but also a bottleneck in other three primary color semiconductor lighting fields.
The three-primary color laser produced by Huang Haojie is made of a new material.
This three-primary color stress material will produce five colors of laser light through voltages and currents of different sizes. Among these five colors, the three primary colors of red, green and blue are included.
The first layer on the silicon wafer integrates the three primary color lasers, and below there are 71 layers of 1-nanometer level integrated circuits, including 7 trillion transistors.
This chip with an area of 1 square centimeter and a thickness of 180 microns integrates 625 million three primary color lasers and 7 trillion transistors.
A makeshift holographic projector is placed on the workbench.
This holographic projector looks like an electronic watch.
In order to avoid damage or dust on the chip surface, the chip surface is covered with a high-strength graphene film.
"Import the operating system." Huang Junjie ordered.
The researcher on the side imported the Taiwei system into the holographic projection chip through wireless import on a computer.
As the introduction began, the holographic projector placed on the workbench suddenly started up.
On the surface of the chip that is invisible to the naked eye, countless lasers are activated instantly, and a scene like an aurora appears above the workbench.
The colorful light spots occupy a space with a side length of about 2 meters and a volume of 8 cubic meters. This space is filled with light.
However, after three or four minutes, the chaotic light spots began to show patterns and outlines.
Gradually, a lifelike display screen appeared in mid-air.
"Test to see if the laser light emitted by the laser will cause harm to the human body."
"OK."
The researchers are busy with testing work. In this laboratory, there are a total of ten holographic projectors that have been produced, and various testing work is being carried out in an orderly manner.
Huang Haojie quietly watched them busy, then turned his chair and thought about the problem of holographic projection technology.
If holographic projection technology is to be truly put into the market, some problems must be solved.
The first is the privacy issue. If a person turns on the holographic projection screen in a public place, there is a high possibility that the people next to him will see the content of the holographic projection screen.
To solve this problem, user sight tracking must be adopted, so that the clearest picture of holographic projection is presented to the user while blurring the sight of non-users.
To put it simply, the picture that users see is clear, while the picture that non-users see is blurry.
The second problem is operational.
Huang Haojieming's holographic projection technology is air medium holographic projection, which means it can be displayed in the air.
In this way, how to operate the holographic projection screen is a question.
There are four solutions: keyboard, gestures, voice, and brain waves.
Brainwave elimination is not something Galaxy Technology cannot do, but the brainwave control system will cause social concern and is not suitable for launch at the moment.
Keyboards, gestures, and sounds can all be considered.