With the emergence of new visual experience technologies such as enhancement reality (AR) and virtual reality (VR), the performance of video devices such as smart glasses and head-mounted displays will also increase year by year. The latest developed laser elements for displaying images on the AR smart glasses are significantly reduced in size.

New Video Experience: Continvenated Ar / VR Market
In the past, traditional TV, PC and displays were only allowed to passively viewed. However, by means of, for example, Ar and VR, one can experience the extended reality by superimposing images, information, and perspective, which images, information, and perspective can vary and adjust according to the action. With the continuous development of video display technology and software, video equipment markets including smart glasses * 1 and head mounted display * 2 are expected to expand in the next few years.

Market size of smart glasses / head mounted display

Upfile
Source: Corporate Society Fuji Camei Practice, 2020 Electronic Equipment Global Market Total

In the near future, Ar is expected to develop further. For example, in a real environment in the game of smartphones, people can test furniture in the room before purchasing in a real environment and in CG simulation applications. Wearable equipment such as smart glasses is also entering the market. They are increasingly put into practical use, such as in the factory, can guide employees to put this glasses, guidance for work procedures, or visitors in the museum to get information about exhibiting works. However, due to its size and weight of the display and laser assembly, the earlier version of smart glasses have problems in wearable, appearance, and comfort. In order to improve the quality of the Ar experience, a smaller and lighter device is needed.

The new laser module can be greatly reduced
Conventional AR compatible smart glass modules reflect both the tricho (RGB) from the laser element onto the lens and mirror, and then project them into a single beam light to display the image. This type of space called spatial optical module requires multiple components, and the disadvantage is that the volume is large.

To solve this problem, TDK focuses on new planar waveguide techniques * 3, which does not need to use the lens and does not need to use a mirror, so the module size can be greatly reduced. The planar waveguide technology developed by the advanced optical telecommunications technology company NTT can combine RGB light by planar path (waveguide), combined with the high-precision manufacturing technology of TDK, which can reduce the size of the final module to conventional spatial optical modules. One tenth of size. This also enables images to achieve a full-color display of up to 16.2 million colors, and high quality images will further improve the quality of the AR experience.

New optical module based on planar waveguide technology

Upfile
This new technique combines the light emitted by the laser element through the planar path, which can achieve full color display of about 16.2 million colors in the ultra-small laser module.
Upfile
(Left) uses the product image of the spatial optical module. (Right) Use the product image of the new planar waveguide module. The reduced module size helps to reduce the size and weight of smart glasses from the whole.
The laser beam emitted from the new module is visualized to the MEMS mirror and then reflects from the lens and projected directly into the retina of the eye. Unlike people to see the real object, the images directly projected to the retina will always be clear without adjusting the focus. When used in the AR glasses for layering images in an environment view, all elements are focused, allowing a more realistic, better AR experience.

Beginning actual application as a visual auxiliary element
TDK's ultra-small laser module is currently integrated into smart glasses visual aids to utilize the actual functionality of this technology - the clear image is directly projected onto the retina. Such auxiliary devices are equipped with a camera in the center and directly imaging into the retina, such that the user can see a clear image that is not affected by the influence of the eye dijfded portion (ie, the cornea, lens). TDK interviewed the QD Laser, Inc. of the smart glasses auxiliary tools, T-kind, Trump Technology Director of the Visual Information Equipment Department. "When we hear the concept of a 'visual auxiliary' device relative to hearing aids, we found that this direct imaging technology actually has true potential to solve visual issues. Near, farming, people, or old anthramies may not need to use Correcting glasses or contact lenses can see the projected image. "

In addition, Suzuki said that with the continuous development of the display technology, smart glasses may become smart devices in the future. "We believe that once we can improve clumsy and uncomfortable design, reduce size and provide the same amount of information as current smartphones, smart glasses will truly leap in the next few years. Although we are still unable to achieve this goal, But we hope that the ultra-small laser module will become a key component that overcomes existing challenges. "

Application in visual auxiliary products

Upfile
At present, the laser module of TDK is currently being used in smart glasses, which supports the image directly to the retina to assist visual.
(Photo provided by QD Laser)
TDK manufacturing technology developed from HDD head machining
The ultra-small laser module achieves the manufacturing techniques accumulated in the production of various electronic components for many years. The method involved in the HDD head precision machining is derived from a laser element (about 100 μm) (a width of about 100 μm) (about 100 μm) (a width of about 100 μm), referred to as a carrier. In addition, the manufacturing process of the HDD heat-assisted magnetic recording head also adopts techniques for connecting nanometer laser elements. Suzuki explains why the laser module of TDK is selected for the company's smart glasses product. "TDK has a wealth of functional components design and manufacturing knowledge, and can be flexibly respond to new products. Another reason is the advanced check function of TDK."

The practical application in the ultra-small laser module in the display technology of the AR is growing. These tiny modules are expected to be increasingly integrated into smart glasses (probably the next after smartphone) and video devices, such as compatible with VR-mounted display and overtaking projector, and have huge potential in the future. .

the term
Smart glasses: wearable devices of the shape like glasses, usually equipped with an AR display. Use Wi-Fi or other way to connect to a smartphone or computer. It can superimpose various information on the actual surrounding landscape and may replace smartphones to become future smart devices.

Headmark Display (HMD): a video display device wearing on the head for VR. More and more widely used in entertainment, medical and industrial uses.

Plane waveguide technique: The technique forming optical waveguide is similar to the optical waveguide in the fiber, but on the planar substrate.