LED lighting solutions provider Signify is leading a pilot project in Seville’s Infanta Elena Park, Spain, to enhance the safety of visitors using solar lighting. For this project, 20 Philips SunStay solar street lights are to be installed in the park.
By integrating solar panel, luminaire, charge controller and battery in one housing, the Philips SunStay street lights are compact and easy to install and maintain. They will also help Seville, a city committed to sustainability and ecology, to reduce energy costs and improve its carbon footprint.
"Seville is a city committed to the fight against climate change and a model of a sustainable city that meets the objectives of the strategic plan Sevilla 2030 and the UN Sustainable Development Goals,” said Juan Espadas, Mayor of the City of Seville.
“All the municipal electricity supply is converted into 100% renewable energy. That is why it is so important that one of the green areas in the city is where we will develop an innovative business project to find solutions that improve citizens public spaces usage and, at the same time, contribute to the reduction of emissions and sustainability."
Philips SunStay street lights save on cabling costs, reduce carbon footprint and lower overall capital and operational expenditure. With an output of 3,000 lumens of warm light and an efficacy of 175 lm/W, they’re more efficient than existing solar street lights, claims Signify.
The lighting of the park allows the practice of outdoor sports outside the existing facilities during the night, as well as maximizing the use of this green space of the city by neighbours and visitors.
“We’re very pleased to show the relevance of solar lighting in European countries,” said Harsh Chitale, Business Group Leader Professional. “I’m confident that many more municipalities will adopt solar street lighting installations in Europe, supporting this market segment’s strong growth expectations for the coming years.”
The new lighting has been installed in the month of June in a shorter time than necessary for conventional public lighting, due to civil works and installation of wiring, reducing the cost and inconvenience to citizens.
Global smartphone display shipments plunged by 20 percent sequentially during the first quarter and are poised to drop again in the second and third quarters, as the U.S.-China trade war worsens the wireless market’s woes, according to business information provider IHS Markit.
IHS Markit reported that shipments fell to 409 million units during the first three months of 2019, down from 512 million in the fourth quarter of 2018, seeing shipments decline year-over-year by 9 percent compared to the first quarter of 2018.
The market research firm anticipates that the second quarter will bring further decrease, 8% year-over-year in smartphone display shipments, followed by a 12 percent drop in the third quarter. While the smartphone business was already facing a number of headwinds in the first quarter, including market saturation and delayed replacement cycles, the drop in display shipments in the second and third quarters reflects mounting concerns about the impact of the trade dispute on global wireless demand.
“With its position at the forefront of the supply chain, the display business serves as an early indicator of smartphone market trends,” explains Hiroshi Hayase, senior director at IHS Markit. “Right now, that indicator is flashing warning signs as smartphone OEMs and ODMs reduce their display orders. Although other factors are negatively affecting smartphone demand, supply-chain participants now are expressing specific concerns about the repercussions of the trade war and the United States’ move to ban Huawei.”
Displays represent the most expensive component within smartphones and therefore are the first sector to experience order reductions when smartphone brands and manufacturers undergo a softening in demand.
In May IHS Markit reduced its smartphone demand forecast by 1.7 percent due to the U.S.-China trade friction, particularly the Huawei ban. Huawei is a fast-growing player in the smartphone market, with the company in 2018 rising to take second place in the smartphone business, surpassing Apple. As a result, the ban is having an impact on the larger businesses of smartphones and their displays.
Despite the overall decline in smartphone display shipments, the active-matrix organic light-emitting diode display (AMOLED) market is expected to continue to expand in 2019, with main smartphone AMOLED supplier, Samsung, unaffected by the U.S. Huawei ban.
One of the key processes in OLED production is the laser lift-off process (LLO) whereby a thin profile UV laser beam is used to lift off the various functional layers of an OLED display from its glass substrate.
Once the OLED layers are complete, the film is separated from the glass substrate by sublimation with a UV laser (laser lift-off).
Solid-state lasers are now also available for use with this process. With a comparable output, these lasers are superior to the excimer lasers that have typically been used up to now, primarily in terms of operating costs. Solid-state lasers deliver excellent beam quality, usually in a Gaussian beam profile. With the aid of special micro-optics, several of these laser sources are transformed into the profile needed for LLO, with lengths of up to 1,000mm and widths of less than 50µm. For example, LIMO’s Activation Line UV line beam shaping system has been used for years with great success for OLED lift-off processes in the production of flexible mobile phone displays.
The development team at LIMO has now enhanced the optical design far enough that the Gaussian profiles can be turned into a line with a length of up to 1,000 mm and a width of 30µm. The new features include significantly steeper edges and a wider intensity maximum. This allows the laser energy to be used much more effectively to separate the display film, and LLO process productivity can be increased by more than 30%. In addition, the sensitive OLEDs are subjected to lower thermal loads (lower ash value), yields are higher, and the OLED displays produced have a longer lifespan.
The new micro-optics for the sGauss profile are modular and feature a continuously adjustable line length and width. Existing systems can also be retrofitted with an sGauss module. This allows manufacturers to either directly boost productivity or, where less laser energy is used with the same systems, significantly extend the service life of their lasers.
The technologies seeking to unseat ITO (Indium Tin Oxide) are by now themselves old, at least in the sense that they have been around for a decade and a half, but they now have to compete on flexibility and foldability too if they are to be successful in flexible displays.
Leading Analysts at IDTechEx have been researching the technology and market landscape for the past eight years, but it is only from late 2018 to early 2019 that a series of foldable displays products were announced, some already in the customers’ hands. In its report, “Transparent Conductive Films and Materials 2019-2029: Forecasts, Technologies, Players” IDTechEx notes that every display company is building up the capability to develop and manufacture flexible/foldable displays, all of which will require some type of flexible touch technology.
Film vs on-cell: a story of trade-offs
The analysts saw flexible touch technologies emerge as two distinct approaches: film and on-cell types. In the former case, a flexible film is bonded atop the OLED device. In the latter, the touch layers are deposited and patterned directly on, or perhaps later as part of, the thin film encapsulation (TFE).
The table below provides a comparison of the two approaches. Film-type is the simplest to implement. Crucially, it decouples the production yield of the touch layer from that of the display layer. Furthermore, the films could be manufactured using lower cost assets. The scalability to larger areas will also be simpler and production speeds likely higher as R2R film production techniques can be deployed. Therefore, the film-based approach is a more accessible technology that offers an easier and lower cost roadmap towards larger-area flexible displays.
However, this approach falls short on performance. Material choices are now available which offer high flexibility and foldability. Metal mesh films are likely to be good enough for medium levels of folding. The picture for higher bending degrees becomes hazier, however technology options such as silver nanowires have already demonstrated that they can sustain the technology roadmap towards high bending levels. Clearly, all technology choices require further improvement however current issues are unlikely to be a fundamental showstopper. As such, transparent conductive layer technology choice itself is not a performance bottleneck.
The real limitation of the film-based approach is that it requires an additional substrate plus an additional bonding layer. This increases overall thickness, which in turn lowers flexibility.
Combining the touch with other layer functionalities may partially alleviate this shortcoming. This trend towards combinations will accelerate perhaps with wide availability of CPI films. Candidates for function combination include the hard coat layer, the polarizer, the barrier film (if film is used), and so on. The evolution of this trend can have important implications for the long-term viability of film-based solutions.
In the comparative table, ‘low’ means lower than the other, the same applies to ‘high’. Another key parameter is the ability to sustain ever tightening foldability requirements. A thinner solution will offer higher foldability but this may need to be balanced by mechanical robustness and lifetime.
The other approach is on-cell. Here, the touch layers are deposited and photolithographically patterned inline directly on top of the OLED-TFT stack. In the future, it might be possible to weave the patterned touch electrodes as part of the TFT structure, although that can require a difficult manufacturing challenge.
The key advantage of this approach is that it eliminates the additional substrate, thus resulting in a thin and flexible solution. The challenge, however, is that it dramatically increases the cost of production defects in the touch layer as the entire stack- including the OLED and the TFT- will be thrown away.
Success here, therefore, requires outstanding production know-how and optimization. Furthermore, this process ties up more expensive production assets on a usually low-cost item which is the touch layer. It is also likely to require slow and controlled deposition within the narrow parameter space limited by the already-deposited materials and layers. Importantly, it is not clear whether this approach can be readily scaled to larger areas or not. This is because one would require the inline TFE as well as the patterned touch electrode deposition processes to be scaled up without compromising quality or cost.
In its assessment, IDTechEx Research anticipates that all display makers will build some know-how for both just in case, but that no single approach will totally prevail in production soon.
Photos of prototyped flexible displays, mostly from 2019
(Source IDTechEx and TCL).
Those with sufficient technology know-how and IP protection will pursue the on-cell approach for the current display sizes. They will also continue to make progress on translating this technology to ever larger areas, often chasing a high-priced high-performance premium display positioning. Others will pursue a film-based strategy, giving them easier and low-cost access to touch technology for flexible displays. In the medium term, IDTechEx envisages that a more diverse range of flexible display products will emerge, each offering a different performance. This will further sustain the existence of multiple approaches in the market.
Note that the battle between film-type vs on (or in)-cell type is also in force in rigid displays. Here too, both approaches are used although, trends can shift the balance one way or the other.
A joint project between Penn State University and OLED luminaires designer OLEDWorks aims to increase the amount of light extracted from OLED-based luminaires.
For this project, Chris Giebink, associate professor of electrical engineering at Penn State, has been awarded a two-year, $1.1 million grant from the U.S. Department of Energy (DOE). The research, which is being conducted in conjunction with Michael Hickner, professor of materials science and engineering, chemical engineering, and chemistry, is focused on increasing the efficiency of OLEDs used for room lighting.
“Because this is a two-year grant, the research is fast-paced and intense,” Giebink said. “The product of this particular grant ideally will be something that we translate into commercial production with our industry partner, OLEDWorks. This gives us the chance to have real-world impact in the near term, which would be gratifying.”
“Right now, only about 20 percent of the light that’s generated in OLEDs gets out,” explains Giebink. “The rest is trapped in the device and wasted.” Overcoming this challenge could make OLEDs more than twice as efficient as the fluorescent lamps currently used in buildings. Over the past 10 years, there have been many approaches for extracting the remaining light out of OLEDs, but so far, no one has been able to do so in a way that’s manufacturable.
“We can implement solutions in the lab at a size of about a millimeter by a millimeter, but doing it on a scale of meters in a way that’s actually compatible with manufacturing is the real challenge,” Giebink said. “That’s where our project comes in. We’re not trying to scatter the light out. We’re actually changing the makeup of the organic semiconductors to change their refractive index, which is an indication of how fast light propagates in a material. What we’re trying to do is lower that value in the organic materials that make up the OLED because, if we can, it’ll avoid much of the problem to begin with.”
The difficulty with this approach is that trying to change the refractive index of the materials themselves may negate the molecules’ electrical and luminescent properties, which took 10 to 15 years of design work to achieve. An alternative being investigated is to blend in other molecules, to decrease the refractive index of the entire OLED film without adversely affecting the properties of the original molecules. If Giebink and his fellow researchers can blend these molecules effectively, they will work with OLEDWorks to see if they can scale up the work to be manufactured.
“The efficiency of organic LEDs commercially right now is something like 70 to 80 lumens per watt. For comparison, your standard incandescent lightbulb is a little bit less than 20. So, we’re talking about four times the efficiency,” Giebink said. “That’s a big opportunity for energy savings that complements what inorganic LEDs are able to provide.”
Market research firm IHS Markit expects MicroLED display shipments to rise to 15.5 million by 2026, as manufacturing expenses drop. A sharp contrast to 2019 and 2020 when less than 1,000 units may ship, according to the same source.
“Despite their extremely high price tag compared to conventional LCD and OLED panels, microLED displays offer advantages in brightness and energy efficiency that make them an attractive alternative for ultra-small and ultra-large applications,” said Jerry Kang, associate director at IHS Markit. “The manufacturing process for microLED will allow suppliers to reduce their production costs over time. Once the process matures, microLED sales will begin to rise.”
Illustrating this trend, the manufacturing cost of a 1.5-inch microLED display for use in smart watches is expected to fall to one tenth of the current cost by 2026. Meanwhile, the manufacturing cost of a 75-inch display for televisions will drop to one-fifth of its current expense over the same time period. IHS Markit anticipates that manufacturing will reach the maturity threshold in 2024.
“Despite the growth in acceptance, microLED shipments in 2026 will still amount to just 0.4 percent of the global flat-panel display market,” Kang explains. “However, with shipments of nearly 16 million units that year, microLED will have entered mass-market territory, setting the stage for much wider acceptance during the following years.”
In cooperation with US company Leia Inc., is automotive supplier Continental developing an innovative cockpit solution: the "Natural 3D Lightfield Instrument Cluster". The solution brings the third dimension into future vehicles.
A stop sign floats bright red in front of the screen. Rows of houses growing out of the navigation system: Continental wants to revolutionize the display in vehicles with three-dimensional effects. According to Continental’s vision, Lightfield displays will not only enable comfortable 3D perception, but will also raise the graphic possibilities to a new level through highlighting, accentuation and complex lighting effects. According to the automotive technology company, drivers will be able to capture information reliably and in real time, making the dialogue between driver and vehicle more comfortable and intuitive. In contrast to existing solutions can the 3D representation be experienced by all passengers - in the front passenger seat as well as in the rear seats.
Continental praises the Lightfield cockpit as an "evolutionary step in the design of human-machine dialog in vehicles. "The new Lightfield display not only brings the third dimension into the vehicle in a new quality. With this innovative technology, we are also creating a new dimension of comfort and safety in automobiles," explains Dr. Frank Rabe, head of the Instrumentation & Driver HMI business unit at Continental. At the same time, this solution gives vehicle manufacturers the opportunity to enhance the driving experience for their customers and to differentiate themselves from the competition thanks to individual design options". The system should be ready for series production by 2022.
Development partner Leia Inc. is approaching the topic from a different angle. "For us, the car is a larger, more immersive version of a smartphone with full 3D environment capture," explains David Fattal, co-founder and CEO of Leia Inc. "So the implementation of our Lightfield ecosystem with virtual reality gaming, video streaming, social sharing or even e-commerce in the vehicle is a logical consequence”. This might sound somewhat bewildering in view of the traffic hazards posed by drivers handling their smartphones while driving and thus endangering their fellow human beings. But Fattal has another scenario in mind: the self-driving car, in which all passengers are allowed to deal with things that are not safety-critical.
The visualization of content on a wide display specially developed for vehicles is supposed to be more sophisticated and entertaining than on a smartphone. In addition, the new technology makes it possible to use internal or external camera systems for video calls or augmented reality functions. All these options are to be exploited within the framework of the cooperation between Continental and Leia.
Leia's Lightfield technology, which Continental uses in its 3D display, does not require a head tracker camera - a practical and cost-saving advantage. For the first time, passengers in the passenger seat and rear seats can also experience the same 3D image from their sitting positions.
But there is another leap in quality that sets the new system apart from earlier 3D processes: The 3D image of the Lightfield display consists of a total of eight perspectives of the same object, which can vary slightly, depending on the viewing position. Thus, the view of the Lightfield display "wanders" with every change in the viewer's viewing angle. In this way, an exceptionally natural reproduction of information on the display is possible, promises Continental.
This is how Lightfield technology works. (C) Continental
In terms of technology, the decisive factor for this quality is a newly developed light guide with nanostructures. The system does not work with refraction, but with diffraction; the light is directed exactly where it is needed for the optimal 3D effect.
Continental is now adapting Leia's existing technology for use in vehicles. Until recently, either parallax barriers or lenticular techniques were used to create a spectacle-free 3D effect. The 3D effect was achieved by a special method of blocking or refracting light. However, Parallax barrier systems in particular only offer applications for a single user because a head tracker system is required to adjust the 3D views to the exact head position of the viewer. When used for multiple users, including passengers and passengers in the back seats, these systems can also have a negative impact on perceived image quality and luminous efficacy, similar to a filter.
From Continental's point of view, the automotive industry attaches great importance to displaying information of the highest quality. The 3D lightfield application should therefore offer a decisive evolutionary step compared to conventional 3D displays. The system works even in direct sunlight, they say.
In terms of technology, the "Natural 3D Instrument Cluster" is based on Leia’s Diffractive Lightfield Backlighting (DLB). A light guide with diffraction gratings and nanostructures under the display panel ensures precise diffraction of the light and thus a natural 3D effect. The light guide module can be integrated into many commercially available displays. The Leia nanofabrication process can be used for large series and mass production. The company has combined advanced lithography on a large-volume substrate with high yield and competitive costs. It was able to draw on HP's experience.
Leia's Lightfield technology made its US market debut in smartphone displays in cooperation with AT&T and Verizon. Consumers can already enjoy gaming, movies, augmented reality and image sharing in unprecedented 3D quality. The Lightfield experience consists of the Lightfield display and an extensive range of automotive applications that will be provided by Continental in the future.
Continental and Leia are also collaborating on content creation and developer support. Leia currently offers a creative toolkit to convert or create content in Lightfield format with automatic settings for visual convenience.
The Lightfield projection of the new car display has many applications. Warnings from driver assistance systems are displayed in 3D, directions from the navigation system can be displayed even more clearly, and the graphic display of the parking aid - such as the assistant with 360-degree bird's eye view - is to become more attractive in 3D. And the greeting from the vehicle system can be enhanced with the help of 3D animations if, for example, the manufacturer's logo rotates in 3D in the cockpit. "It's important to note here: The 3D animations on our new display don't fly through the car like they do in the cinema," explains Kai Hohmann. "We work with the graphic depth to the rear and allow all 3D objects to emerge from the picture by a maximum of five centimeters. This is more relaxed for the eye, the driver is never irritated."
The cooperation will use Continental's know-how in the field of information systems and sensors to augment the LeiaLoft content platform. This will enable car manufacturers and external developers to easily create holographic apps for future vehicles.
Thousands of young women and girls have had the chance to explore the world of science, engineering, and light technologies thanks to a European photonics research consortium that has created their girls in STEM ecosystem, a series of 33 workshops and 11 Photonics Challenger projects across 10 European countries in a bid to tackle the under-representation of women in science.
According to the UNESCO Institute for Statistics (UIS), less than 30% of the world's researchers are women. However, a new outreach project has been tackling this under-representation by engaging young female minds with STEM, in the hope that they will pursue a career within the photonics, science or engineering industries. Staged in ten countries across Europe, a total of 1221 girls have attended the ‘Phablabs 4.0’ initiatives since last year. The workshops have created novel and innovative problems for students to solve using lasers and photonics, the technology around the emission, manipulation and detection of light.
Combining a ‘Fab Lab’ – or a fabrication laboratory - with the world of photonics, the workshops and Challenger Projects offer a glimpse into careers in photonics, engineering, computer coding, and robotics.
Students have been exploring tasks as varied as creating an artwork made from lasers, modifying a cuddly toy with photonics, or building an infrared glove that acts as a remote control where touching two fingers creates a signal. The more advanced Challenger Projects have tasked students with building an Invisibility Cloak or creating their own hologram.
“Phablabs is amazing and interesting. We’ve learned lots of new skills that we wouldn’t have picked up in school. To see the job in front of me and to meet the person who does that job has given me loads of ideas about what I can do in the future. It’s really made me want to work with photonics”, commented Ester Muylaert, 18, from Halle, Belgium, one of the many attendees.
The researchers have targeted three age categories with workshops aimed at high school girls (Young Minds), female university students (Students) and women who may have already started their careers (Young Professionals 18+).
One of the results of the PhabLabs 4.0 project has been the publication of a new booklet, A Gender Balanced Approach as a guide to future Fabrication Laboratories so that organisers in schools or universities can use it as a reference to gain the interest of girls and young women in science and technology.
By creating gender-sensitive material for the workshops and “Photonics Challenger Projects” the organisers have garnered the interest of girls and young women in science, to generate a lasting impact on their personal relation to STEM and Fab Labs. Supported by the Gender Action Team, the developers have had the backing of the European Commission with funding from Horizon 2020, and support from a number of professionals such as Professor Averil MacDonald from WISE (Women in Science and Engineering).
“Girls and young women are more likely to consider studying STEM subjects beyond age 16 if they see that the subject keeps their options open”, said Professor MacDonald.
“The STEM sectors can only benefit from the talents of these young women. More girls and young women deserve the chance to have successful and satisfying careers in science, technology, engineering, manufacturing, mathematics and construction”. The resources are available as an open resource toolkit for educators to use with their students.
Dialight’s Reliant industrial LED High Bay range is designed to deliver superior energy efficiency for warehouses, light manufacturing and other large indoor spaces.
Available in the EMEA and APAC markets, the industrial LED fixtures feature a rugged new form factor, with the option of adding or retrofitting integrated controls, allowing for smart sensor installation at the center of the fixture, which ensures maximum return on investment. The sensor and automation options just plug in and play, so can be easily added at manufacturing stage, later during installation or retrofitted at a later date. Reliant also offers field-replaceable lenses, multiple optical patterns, and a 10kV optional surge protection upgrade for superior on-site customization and flexibility and is available in 11,000 to 36,000 lumen output to accommodate a broad range of mounting heights.
Reliant is backed by Dialight’s 10-year warranty, among the industry’s longest, best-in-class protections, with an L-70 rating at 55°C and L-90 rating at 25°C for 100,000 hours. The new fixture is simple to install with single-point suspension and easy access to the wiring compartment for service and on-site upgrades, it delivers up to 160 lumens per watt—for 1-to-1 replacement, and 1-for-2 in some cases, of existing HID fixtures. Its robust 6kV/3kA built-in surge protection is field upgradable to 10kV, while Dialight’s exclusive purpose-built, in-house designed power supply and thermal management system ensure optimal reliability and longevity of critical components.
Reliant is compatible with DALI 1.0 and 2.0, wired occupancy and daylight harvesting sensors, as well as Dialight IntelliLED wireless controls for automated lighting configuration and seamless integration with existing building automation solutions.
Diodes Incorporated’s AL5822 LED current ripple suppressor delivers a high level of ripple current suppression in single-stage, high power LED installations, even when triac or PWM dimming techniques are being used to vary the light level.
This ensures there is no sign of flicker or strobing across the entire dimming range, while still maintaining a high power factor.
The AL5822 has been designed and tested to comply with the Title 24 building code requirement of less than 30% flicker. The device has been demonstrated to suppress over 97% of ripple while still achieving a power factor of greater than 0.9. By monitoring the current flowing through the LEDs, the AL5822 compensates for ripple by adjusting the drive voltage for the external MOSFET. This control loop keeps the MOSFET operating in the saturation region to deliver a constant current.
With support for various pre-stage circuits, the chip can work with a number of drivers, such as the AL1665 single stage PFC flyback buck/boost controller, also from Diodes Incorporated. The device doesn’t require magnetic discrete components, minimizing the overall bill of materials. It operates over an input voltage range of 24Vac to 305Vac. Safety features include LED short-circuit, over-temperature, and over-current protection.