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 | firstname.lastname@example.org
Winterbergstraße 28 | 01277 Dresden | Germany | www.fep.fraunhofer.de
Annett Arnold | Fraunhofer-Institut für Organische Elektronik, Elektronenstrahl- und Plasmatechnik FEP
Nagoya University researchers break down plastic waste
29.05.2017 | Nagoya University
A new tool for discovering nanoporous materials
23.05.2017 | Ecole Polytechnique Fédérale de Lausanne
The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.
The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
29.05.2017 | Life Sciences
29.05.2017 | Physics and Astronomy
29.05.2017 | Statistics