At the SID Display Week, June 2 – 4, 2015, in San José/USA (German Pavilion, booth no. 222) the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP will present a coating which is required to expand the diameter of a laser beam by more than factor of one hundred. With this coating, backlighting for holographic displays can be realized in the future.
Wouldn‘t it be exciting to sit in the midst of a film without wearing annoying 3D glasses? Not only for television fans, holographic displays would be a giant step in this direction. Medical scientists could inspect spatial images of the inside of the body and observe detailed movements of organs.
The company SeeReal Technologies in Dresden works on such displays. Holographic displays use certain properties of laser light for the complete three-dimensional display of images. Therefore, an expansion of the laser beam to the display size is necessary. One can easily imagine that a laser beam with a diameter of a television display is difficult to realize. A conventional option would be large lens systems, but these are clunky and can only be manufactured complexly and at very high costs.
In a joint project with SeeReal Technologies the scientists of Fraunhofer FEP have now developed coatings that enable usage of low power lasers for illumination. The laser is directed in at a very flat angle into a glass plate (here 5°, respectively 85° against the vertical). Similarly to the shadow of a person which is extending in the setting sun and whose projected area on the earth also extends, the diameter of the laser beam increases. A small spot becomes an elongated ellipse.
In a second step the elongated ellipse impinges again on a second glass plate at 5°, whereby the second direction of the ellipse, the “short axis”, is elongated. Thus the laser spot is expanded to a circle, that is large enough in order to illuminate the entire display. However, if you shine with a laser on an uncoated glass plate at such a flat angle, approx. 73% of the beam is reflected. In case of two “expansion steps” more than 90% of the original intensity would be lost!
„We have developed an anti-reflective coating which increases the part of the transmitted light significantly”, says Dr. Daniel Glöß, head of the “Dynamic coatings” department of the “Precision Coatings” division at FEP. “By means of magnetron sputtering, thin layers are deposited on glass. These layers consist of two different materials with varying optical density. Even complicated optical functions can be achieved via multilayer systems, which, for instance, let only certain colors of the light pass through and reflect the others.”
With its new precision coating plant PreSensLine, Fraunhofer FEP is optimally equipped for the high-precision coating of larger substrates. Thus functional panes of size DIN A3 (approx. 300 × 400 mm² or 28” screen diagonal, respectively) have been coated with the special multilayer system. The specific challenge results from the combination of extreme requirements regarding the precision, reproducibility and homogeneity of the layers on this large area.
As in conventional color televisions, the color impression with holographic displays should result from a mixture of red, green and blue, whereby a white picture is created by overlapping. For this demonstrator 24 layers are required for the anti-reflective coating. The layer thickness of all 24 layers had to be hit correctly down to a few millionths of millimeters (nanometers) and must also remain constant over the whole area. That is equivalent to only a few hundred atomic layers or in other words: Would you enlarge the coated plate to the size of a football field, the allowed tolerances of the individual layer thicknesses would correspond approx. to one-hundredth of the thickness of a human hair. Even slightly larger deviations lead to loss of the desired anti-reflective properties. The picture quality would be strongly impaired or the color of the picture would appear distorted.
The anti-reflective coatings, which were manufactured at Fraunhofer FEP, were installed into the demonstrator of SeeReal Technologies. There, holography has already become reality. To produce significantly larger displays in the square meter range with the same precision is an ambitious goal. To achieve it, Fraunhofer FEP is also well equipped. It has the latest state-of-the-art pilot plant technology as well as the know-how for manufacturing demanding layer systems for the customer-specific development and production of the required coating components.
Find out more about our work:
Bidirectional Expansion of Collimated Laser Beam as Backlight for Holographic 3D Display
Speech at the Exhibitor Forum, Session 6: Innovative Display Technologies and Applications
Thursday, June 4, 2015 | 9.15 a.m. | Executive Ballroom 210
Roll-to-Roll Manufacturing of Functional Substrates and Encapsulation Films for Organic Electronics: Technologies and Challenges
Speech at the Symposium: 10.1 (Invited Paper),
Tuesday, June 2, 2015 | 2.00 – 2.20 p.m. | Ballroom 220C
SVGA Full-Color Bidirectional OLED Microdisplay
Speech at the Symposium: 15.5 (Late-News Paper)
Tuesday, June 2, 2015 | 5.00 – 5.10 p.m. | Ballroom 220B
Advanced Processing of ITO and IZO Thin Films on Flexible Glass
Poster on the Poster Session: Display Manufacturing, P.65
Thursday, June 4, 2015 | 4.00 – 7.00 p.m. | Ballroom 220A
Optimized anodes for flexible large area OLEDs
Poster on the Poster Session: OLEDs, P.133
Thursday, June 4, 2015 | 4.00 – 7.00 p.m | Ballroom 220A
Mrs. Annett Arnold
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP | Phone +49 351 2586 452 | email@example.com
Winterbergstraße 28 | 01277 Dresden | Germany | www.fep.fraunhofer.de
Annett Arnold | Fraunhofer-Institut für Organische Elektronik, Elektronenstrahl- und Plasmatechnik FEP
New biomaterial could replace plastic laminates, greatly reduce pollution
21.09.2017 | Penn State
Stopping problem ice -- by cracking it
21.09.2017 | Norwegian University of Science and Technology
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
21.09.2017 | Physics and Astronomy
21.09.2017 | Life Sciences
21.09.2017 | Health and Medicine