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There is no doubt that the use of LCD headlamp is a succcessful further step towards digitalizing lighting. LCD headlamp which enables complex functions will also be relevant to autonomous driving. Let's talk something about the following research project about developing a headlamp basics on a LCD (  Full name is Liquid Crystal Display )which made by HELLA and seceral partners.This technology is an good example already known in the home entertainment field.  About The ProjectIn the context of the research project funded by the Federal Ministry of Education and Research (BMBF) regarding the fully adaptive light distribution for intelligent, efficient and safe vehicle lighting (VoLiFa2020), HELLA has developed a headlamp on the basis of a Liquid Crystal Display (LCD) in collaboration with project partners Merck, Institut für Großflächige Mikroelektronik IGM, Stuttgart University, Porsche, Elmos Semiconductor, Schweizer Electronic, and the University of Paderborn. Complex FunctionsIn general,the new LCD headlamp projects 30.000 pixels onto the road. This allows adjusting the light pattern in an intelligent and continuous manner to various driving situations in real time. The use of an LC display is a further step towards digitalizing lighting. This means: the adaptation of the light pattern will increasingly be determined by software. The driver will obtain the best possible view of the road. Individual segments with e.g. other traffic participants or strongly reflecting street signs can be omitted or dimmed in a targeted manner. Highly complex functions are also conceivable: navigation arrows or lines showing the ideal lane can be projected onto the road. LCD technology enables functions that will also be relevant to autonomous driving.  The LC display is the headlamp’s key component. It is situated between the LED light source and the projection lens. The display generates a matrix with 100 x 300 pixels that can be individually controlled and dimmed. A camera installed in the vehicle as well as a sensor optically reading distances and speeds (light detection and ranging sensor, LiDAR), will forward the ambient information to the headlamp control unit via a processor. This will then direct the individual display pixels up to 60 times per second. 25 high-power LED’s arranged in three rows will serve as light source. Each LED’s light intensity will be adjusted to the respective lighting situation. Due to increasing traffic volumes and safety requirements, intelligent lighting systems are of increasing importance. LCD technology enables completely new functionalities and opportunities here. And the use is not limited to passenger cars. Other vehicle categories, such as commercial vehicles or buses also provide meaningful application areas. ThanksgivingThanks to this project's great resolution and sharpness of detail, it opens up a diffirent new paths in automotive lighting technology. 

Today I want to share a project of making a simple automatic street light controller using relay and LDR I found in circuitdigest with you.   You have seen street light which automatically gets turned on in the night and gets turned off in the morning or day time, there are sensors who senses the light and control the light accordingly. These Street lights are an important project in smart cities.   So here in this project, we are going to make a Simple Automatic Street Light Controller Using Relay and LDR. This circuit is very simple circuit and can be built with Transistors and LDR, you don’t need any op-amp or 555 IC to trigger the AC load. Here we have used an AC bulb as street light. Some applications of this circuit are street light controlling, home/office light controlling, day and night indicators, etc.   Components Required:   Transistor BC547 -2 LDR (Light Dependent Resistor) Relay Resistor 1k 100k Potentiometer Power Supply 12v -1 Connecting wires Jumper wires Screw terminal Block 2 pin or 3 pin Bread Board or Perf Board 1n4007 Diode AC supply AC Load or Bulb   Here you may want to know: what is LDR? LDRs are made from semiconductor materials to enable them to have their light sensitive properties. There are many types but one material is popular and it is cadmium sulphide (CdS). These LDRs or PHOTO REISTORS works on the principle of “Photo Conductivity”. Now what this principle says is, whenever light falls on the surface of the LDR (in this case) the conductance of the element increases or in other words the resistance of the LDR falls when the light falls on the surface of the LDR. This property of the decrease in resistance for the LDR is achieved because it is a property of semiconductor material used on the surface. LDR (Light Dependent Resistor)   Circuit Diagram and Explanation:   Below is the circuit diagram of this Light sensing Street Light:       In this project, we have used an LDR (Light Dependent Resistor) which is responsible for detecting light and darkness. The resistance of LDR increases in darkness and reduces in presence of light. This circuit is same as a Dark Detector or Light Detector Circuit, only here we have replaced simple LED with a AC load, using a Relay. Two BC547 NPN transistors are used to drive the relay. Automatic Street Light circuit using LDR and relay   Whenever light falls over LDR its resistance get decreased and transistor Q1 turns ON and collector of this transistor goes LOW, and this makes the second transistor turns OFF due to getting a LOW signal at its base, so relay also remain turned OFF due to second transistor.   Now whenever LDR senses Darkness, mean no light, then transistor Q1 turned ON due to increase in the resistance of LDR which is responsible for voltage drop at the base of Q1. Due to a LOW signal at the Q1 base, Q2 transistor gets a HIGH signal from the collector of Q1 and turns ON the relay. Relay turned ON the AC load that is connected to relay. A 10K pot is also used for setting up the sensitivity of the circuit.   So this is how automatic Street Lights turns on in the night and turn off in the day, and below is the effect pictures. >>>>>                                                       > >>>>   Ref. KY56-BC547A KY32-1N4007  

The US Department of Energy (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) has detailed a living laboratory test of solid-state lighting (SSL) and controls on a 40,000-ft2 floor in a New York commercial office building. Berkeley Lab worked with the Building Energy Exchange (BEEx) on the LED lighting project that also included comprehensive light and occupancy sensors along with connected window shade controls. Berkeley Lab believes the work will speed market adoption of smart lighting and the BEEx will use the work to further its educational mission, serving lighting designers and specifiers that are working on commercial spaces.Lately, much of our coverage about smart lighting and the Internet of Things (IoT) has been focused on what lighting-based connectivity can offer in supporting new applications and services such as indoor positioning, security, asset tracking, and more. For example, Acuity Brands said earlier this year that it has deployed indoor positioning technology in 20 million ft2 of retail space. The IoT hype can make it easy to forget that networked control of lighting and shades confined to a space such as an office floor can deliver tremendous benefits in energy used.Still, roadblocks to more smart lighting installations remain. “Context matters when it comes to figuring out where the market barriers are with respect to contractors, facility managers, and office workers — isolated tests in a laboratory environment are often not enough,” said Eleanor Lee. “Reducing stakeholders’ uncertainty about performance and occupant response in a real-world setting can be critical to accelerating market adoption.” Lee is the Berkeley Lab scientist that led the New York project intended to document the benefits of smart lighting in a working office space — thus the characterization as a living lab. Berkeley Lab and BEEx collaborated on an office smart lighting trial in New York City that combined SSL with sensors and window shade controls. Indeed, the project team monitored energy usage and other characteristics of the office space for a full year before the retrofit to SSL and controls took place. BEEx acted as the local manager of the project.As the nearby photo illustrates, the retrofit replaced fluorescent T5 lighting with dimmable LED fixtures delivering direct and indirect lighting. The floor-to-ceiling windows received automated shades. And connected sensors spread throughout the mostly-open space can detect localized light levels and occupancy.The test further considered thermal elements of the space given that the ubiquitous windows and daylight can heat a space. The test included the use of linear slot diffusers along the top of the windows that can mitigate rising temperatures. And underfloor air distribution (UFAD) diffusers were used to improve airflow and allow for localized control. Thermal imaging was used to document acceptable temperatures throughout the retrofitted space.The smart lighting project sought to balance the benefits of natural light with visual and thermal comfort and provide workers with enjoyable views when possible. Shades had to be lowered at times to mitigate glare but could be opened at other times, both reducing the need for artificial lighting and fully revealing views for the office.The study focused on the 40-ft perimeter zone of the office floor. Compared to the measured baseline, the electricity required for lighting dropped 79% over the course of six months in which BEEx has monitored the installation. Peak electrical demand dropped 74%.The study did not measure energy dedicated to powering the HVAC (heating, ventilation, and air conditioning) system in the space. But the researchers did estimate the impact on HVAC energy and also projected the measured data to suggest an entire building retrofit would have delivered savings of $730,000 per year. Based on installation cost of $3–$10 per square foot, an entire building project would pay back in 3–12 years.BEEx will take the results of the project to help the lighting community with tools and other resources. “Using everything we learned on this project,  we've developed a series of tools that will really help the engaged design professional or building owner make better decisions about lighting system upgrades, and avoid the common pitfalls on the road to a high-performance office space,” said Yetsuh Frank, BEEx managing director of strategy and programs.The Berkeley Lab has not been as involved in the SSL sector as has the DOE Pacific Northwest National Laboratory (PNNL). PNNL has been behind many of the DOE Caliper and Gateway projects. We have covered many of those reports such as a recent Gateway report on four common indoor lighting applications.Still, the Berkeley Lab is adding to the DOE’s SSL initiative. About a year back we reported on a Berkeley project involving solar-powered LED lighting outdoors where the researchers said such lighting could create 2 million jobs in developing regions. Ref.591-2201-013F591-2001-013F 

Diodes Incorporated introduced the BCR401U, BCR402U and BCR405U. Appealing to lighting designers, these constant-current regulators enable simple driving of low- current LED strips and panels in the commercial and industrial lighting sectors. Targeted at 12 V and 24 V linear LED strips, these regulators increase light output efficiency as they only require a 1.4 V supply, allowing more LEDs in the string. By achieving regulation within ±10% and providing preset options of 10 mA (BCR401U), 20 mA (BCR402U), and 50 mA (BCR405U) that can be adjusted up to 100 mA, these regulators simplify the design, minimize component count, and overall enhance system reliability by integrating the driver. Combined with the improved efficiency and longer life offered by LEDs, many lighting applications including advertising, emergency, refrigeration, decorative, architectural and other general forms are being superseded with this emerging light source.  Delivering a regulated current over a wide 1.4 V to 40 V supply, the BCR40xU will tolerates voltage spikes and LED short failures in strings, whilst preserving LED brightness and longevity. This, along with a negative temperature coefficient that reduces the LED current with rising temperature, helps to increase the LED lifespan by reducing dissipation and additionally enables parallel device operation for increased current in applications requiring more than 100 mA. The BCR40xU operates as a linear LED driver, minimizing the likelihood of EMI, which is particularly important in medical lighting and other sensitive applications, while LED brightness can be PWM controlled with <1% duty cycle at 25 kHz allowing accurate dimming to low light levels. The BCR401U, BCR402U and BCR405U LED drivers are offered in the industry-standard SOT-26 (SC74R) package. Ref.KY32-BCR401U E6327KY32-BCR402UKY32-BCR405UE6327  

It takes a very, very clean room to build a detector sensitive enough to see the light from the beginning of the universe.Work is underway at the U.S. Department of Energy's (DOE's) Argonne National Laboratory on a new "clean room." The new lab will be specially suited for building parts for ultra-sensitive detectors—such as those to carry out improved X-ray research, or for the South Pole Telescope to search for light from the early days of the universe."This will be a unique facility, and a wonderful investment for the future of the laboratory," said Supratik Guha, who heads the Center for Nanoscale Materials, a DOE Office of Science User Facility adjacent to where the new space will be located.Clean rooms are a special kind of laboratory that is heavily filtered and cleaned, so that no free-floating particles interfere with delicate work. Take a cube of air one foot on a side: In a normal room in your house or office, this cube contains about one million free-floating particles of dust, dirt and other materials. In the clean room, it's no more than 100.This environment is what you need to build detectors that can detect the tiniest amount of energy striking the surface."Even a few stray specks of dust in the niobium can throw off the design for these detectors," said Marcel Demarteau, who heads the High Energy Physics Division at Argonne and will be a key user of the new lab.One use for such detectors is in the South Pole Telescope in Antarctica, one of several telescopes searching for light waves that have traveled throughout the universe since the moments after the Big Bang. This kind of light is called the Cosmic Microwave Background radiation.Because the light has traveled across space for the 13.8 billion years since the universe began, it has encountered all sorts of obstacles that slightly change its power spectrum—galaxy clusters, patches of dark matter, even our own atmosphere. "We have to correct for these to map the Cosmic Microwave Background signature we're looking for, but these small perturbations themselves hold an enormous amount of very valuable information about the composition of the universe," Demarteau said.  The most sensitive instruments today to find such signals are detectors made from superconductors. Superconductors are extremely sensitive materials that change properties dramatically when their temperature is raised even a tiny bit, and scientists can build components that react to specific frequencies to detect the signature of the Cosmic Microwave Background. The new clean room should allow researchers to build even more sensitive detectors—think of a camera that takes 150-pixel pictures versus one that can take 500,000-pixel images.The same technology will also offer researchers a chance to get better close-ups of the atomic makeup of objects being studied at the Advanced Photon Source, a DOE Office of Science User Facility at Argonne where scientists use X-rays to study everything from car fuel injectors to proteins that play roles in disease.The Advanced Photon Source sends beams of high-energy X-rays at a sample of whatever scientists are studying: a new solar cell material, a sample of volcanic glass from Greenland, a protein involved in photosynthesis. The X-rays hit the sample and scatter off in all directions. Very sensitive detectors pick up that scatter and reveal the chemical and atomic layout of the sample. The better the detector, the more information you can get; so Advanced Photon Source scientists are always looking for new ways to improve those detectors."The type of detector we want to build, nobody makes commercially: so we have to build our own," said Thomas Cecil, an engineer with the Advanced Photon Source. The new clean room will allow them to experiment with new kinds of transition edge sensors, which he said they hope could eventually improve the sensitivity by one or even two orders of magnitude compared to traditional silicon-based detectors.Building such technology is an excruciatingly delicate process, in which they lay down multiple coatings just a few nanometers thick—less than a hundredth of the diameter of a human hair—of superconducting materials and etch patterns into them. Then they repeat the process all over again, for up to 15 layers.The detector itself is so precise that it's operated at temperatures colder than outer space to achieve maximum sensitivity. "It's an excellent opportunity for us to push the boundaries of what's possible," Cecil said.Other potential uses, Demarteau said, include quantum computing as well as homeland security: building detectors that can pick out the particular signature of a specific kind of radiation, to detect if terrorists are carrying a dirty bomb made out of, for example, cesium-137. 

New research by scientists from the University of Bristol has revealed that domestic LED lights are much less attractive to nuisance insects such as biting midges than traditional filament lamps.The team now highlights the urgent need for further research on other heat-seeking flies that transmit disease, including mosquitoes that are carriers of pathogens that cause damaging diseases such as malaria and Zika fever.The study, funded by the Natural Environment Research Council and UK lighting manufacturer Integral LED, used customised traps at 18 field test sites across south-west England, illuminated by a series of LED, filament and fluorescent light sources. Over 4,000 insects were carefully identified. The results showed that LEDs attracted four times fewer insects compared with the traditional incandescent lamps, and half as many as were attracted to a compact fluorescent lamp.Notably, for biting flies (midges in the genus Culicoides, some species of which are vectors of wildlife disease), 80 percent were attracted to the filament lamp, 15 percent to the compact fluorescent and only 2-3 percent to each of the two different LED lamps.Dr Andy Wakefield led the field research in a project supervised by Professors Gareth Jones and Stephen Harris from the University's School of Biological Sciences.  Dr Wakefield said: "We were surprised by the number of biting flies drawn to the traditional tungsten lights. We do not know why this is but we know that some insects use thermal cues to find warm-blooded hosts in the night, so perhaps they were attracted to the heat given off by the filament bulb."Co-sponsors of the study, Integral LED were instrumental in the commissioning of the project and provided technical and financial support.The UK company's Marketing Director Sanjiv Kotecha said: "As lighting manufacturers, we welcome that a link between LED lights and low attraction to insects has been proven. The energy saving advantages of solid-state lighting are well known, yet the benefits to well-being are only beginning to be revealed."Reference:ASMT-UYBG-NACJ8XRCWHT-L1-0000-004E6LUWCP7P-KTLP-5E8G-35-Z