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Successful Shooting of Molecular Decomposition Process with Laser

Le 25 octobre 2016, 05:54 dans Humeurs 0

According to the American Association for the Advancement of Science website reported that the United States Kansas State University and the Spanish Institute of Science and Technology in Barcelona (BIST) scientists composed of international research team, the first successful use of the laser with 4 atoms of molecules in 9 femtosecond chemical reaction dynamics process. The new study, published in the journal Science, will provide scientists with powerful tools for observing different types of reaction processes and molecular changes in the chemical, biological and physical sciences.

Femtosecond only one thousand trillionth of a second, many chemical reactions occur in the femtosecond of the moment, had no way to measure the process of femtosecond molecular changes. Using brightest laser pointer to record changes in femtosecond, the first by the Kansas State University physicist Lin Yidong (transliteration) and colleagues, and in 2012 the first time with a laser to capture two atoms of oxygen molecules dynamic decomposition process. And the shooting of larger molecules need to use a stronger laser, after nearly 5 years of long study, Lin Yidong team finally BIST Institute of Optics Jens Bigert team to overcome this challenge, shoot with 4 Atomic acetylene molecules (two carbon atoms and two hydrogen atoms) chemical bond cleavage process.

The international team used a medium-infrared laser induced electron diffraction (LIED) technology, the use of molecular internal electrons for the molecular camera, access to acetylene chemical bond breaking process of continuous shooting pictures. They applied a strong laser beam to the acetylene molecule, activating an electron to leave the molecule, initiating the decomposition of the acetylene molecule, and finally taking a series of pictures for the molecular change that occurred within 9 femtoseconds. "This is the first real-time observation of the molecular decomposition process within 9 femtoseconds."

The team also obtained through the continuous shooting photos, accurate measurement of acetylene molecules within the new chemical bond length. Lin Yidong explained that there are four atoms in the acetylene molecule, the molecular structure contains multiple chemical bonds, with the help of femtosecond 5000mw laser pointertools, researchers can detect the chemical bond break position and order, in order to better understand and control the chemical reaction process.

Ring Laser Interferometer Can be Applied to Natural Disaster Early Warning System

Le 19 octobre 2016, 12:25 dans Technologie 0

In February this year, the US Laser Interferometer Gravitational Wave Observatory (LIGO) successfully detected billions of years ago the merger of two black holes in the process of space-time ripples - gravitational waves. Scientists at the Handelix Institute of Technology in the United States recently published a study in the Journal of Applied Physics that developed a small ring laser 20mw interferometer to detect ground-induced and convective storm-induced Sub-acoustic and other geophysical effects, the future of the technology can be applied to hurricanes, tornadoes and volcanic eruptions and other natural disaster early warning system.

"Essentially, we have confirmed many of the long-term results of the National Oceanic and Atmospheric Administration (NOAA), but we replaced the microphones with ring lasers." Robert Dun, professor of physics at Handelikes College, En said. The ring laser interferometer can clearly show the frequency spectrum of the infrasound, in particular, can be pointed out that the tornado to reach the ground 30 minutes before the laser can detect the tornado generated infrasound. The researchers found that infrasound waves generated by tornadoes could propagate 1000 kilometers away, confirming the results of previous NOAA studies.

How does the ring-shaped laser 10mw work? First, the laser plasma tube emits a laser beam in a clockwise and counterclockwise direction, respectively. If the laser cavity rotates in a clockwise direction, the photons that are also clockwise moved around the laser cavity will take longer and the photons that move in the counterclockwise direction will take less time. Since the speed of light is constant, the length of the path of the laser beam moving in different directions is different, and the difference in path length causes a frequency difference in turn. When the laser beams moving in the clockwise and counterclockwise directions are combined together, a "beat" corresponding to the rotation is generated. The earth has been spinning, using a horizontal ring laser can measure the Earth's rotation. Perturbation of the laser cavity changes the beat frequency of the earth. This means that the infrasound into the 5mw green laser cavity can cause disturbance, which changes the rotation of the Earth beat frequency.

The instrument can detect the infrasonic waves generated 30 minutes before the tornado reaches the ground. Combining with Doppler radar, it has a good application foreground in the early warning system. In addition, because it can detect the rotation of the seismic component, it may be possible to reduce damage caused by the earthquake. In addition to being used in a tornado warning system, ring lasers can detect infrasound waves generated by hurricanes and volcanic eruptions. Volcanic ash can destroy jet engines, ring lasers can detect distant places of volcanic eruptions, so as to ensure that the aircraft in the region flight safety. "Now all the results can be said to be only the beginning, our goal is to continue to explore the ring laser 200mw in disaster prevention and mitigation applications.

Unmanned Vehicles Enter the Data Competition

Le 11 octobre 2016, 10:44 dans Humeurs 0

China's domestic laser radar R & D enterprise RoboSense (Suteng Juchuang) recently announced that it has mastered the core technology of multi-line laser radar, and completed the first generation of multi-line laser radar RS-LiDAR research and development work. The product will be road test in the near future, has not yet announced the price. The advancement of China-made multi-line laser radar research and development may lead to changes in ecology of unmanned vehicles in the lower reaches of the country. The cheaper and more efficient means of data acquisition makes the competition between data acquisition and data algorithms a new threshold. According to RoboSense, multi-line laser radar products can be used in intelligent robots, unmanned vehicles, virtual reality, construction, military cruise and other fields. The product may become the first to enter the practical application of domestic multi-line burning laser pointer radar. RoboSense said, and with the technological progress of the product of a single cost is expected to be reduced to 500 US dollars.

Multi-line laser radar is one of the most important components of unmanned

Driven by the concept of unmanned driving in recent years, the impact of laser radar technology components mentioned by the technology industry has become increasingly frequent. The laser radar is composed of three parts: the transmitting system, the receiving system and the information processing. The laser emits electrical pulses into optical pulses, and the optical receivers then reduce the optical pulses reflected from the targets into electrical impulses, and finally obtain a series of algorithms. Target position (distance and angle), motion state (velocity, vibration and attitude) and shape, which can be detected, identified, resolved and tracked. As we all know, laser radar to play the role of unmanned vehicles eyes, LIDAR more popular than some of the more visible light camera to see more distant, and not affected by external light.

RoboSense completed the core of multi-line laser radar research and development, the key is "multi-line." There are many manufacturers at home and abroad to provide single-lane laser radar solutions, but multi-line (4 lines, 8 lines, 16 lines, etc.) lack of products. Prior to the more well-known multi-line laser radar suppliers only Velodyne and Ibeo. Single-lane lidar has been used in industry for some time, it can obtain 2D data, but can not identify the height of the target information, so the application of single-laser radar in the field of unmanned vehicles, usually as a visual system complement; Radar can identify 2.5D or even 3D data, and the accuracy is higher than the single line, industry-recognized multi-line red laser pointer radar is completely unmanned (L4) level of the best sensor solutions.

LIDAR number and number of data points to determine its technical threshold, but also a powerful evaluation of the radar function of the main parameters.Such as Google and Baidu's unmanned vehicle in the early stages of research and development are used in the highest level and the most expensive 64-line laser radar (Velodyne produced, model is HDL-64E). But the product price of nearly one hundred thousand dollars, even more than the price of a car. And Google in a large number of road test of the third generation of unmanned vehicle products (no steering wheel, throttle, shape like a small bread), taking into account the cost of a slightly cheaper 16-line laser radar. The RoboSense RS-LiDAR is a 16-line lidar. According to the information provided by the official, it uses a mixture of solid form, measuring distance of 100 meters, 2cm accuracy, horizontal 360 degrees, vertical 30 degrees (± 15 degrees), real-time points 320,000 points per second. From the data, even slightly better than Veledyne 16-wire products. RoboSense plans to start a series of road test courses with partners to optimize software and reliability from October this year. If all goes well, this will be the first domestic multi-lane lidar product to be used in the field.

As a key component of a completely unmanned system, China's self-developed multi-line laser radar has brought a significant reduction in the threshold of the entry threshold for unmanned vehicles. There have been car manufacturers, laser radar if the price dropped to 10% of the vehicle, will directly promote the industry change. However, the huge R & D cost and the small purchase amount for the purpose of experiment and development make the cost of multi-line laser radar difficult to dilute. It is reported that Baidu's investment in Veledyne, you can get its flagship product of 500,000 yuan each of the "preferential" supply price. On the other hand, China's domestic 1000mw laser radar industry is limited by technical strength, in the absence of the most promising sunrise industry, the lack of voice. But also makes the domestic application of unmanned research and development and industrial ecology faces many challenges.

In the Chinese manufacturing industry chain integration of the most adequate of the Pearl River Delta, the application of technology quickly and efficiently landed as a product, and through market and financial means to reduce costs, is already a mature routine. RoboSense in Shenzhen, if able to seize the opportunity to launch under the same parameters, the price is far lower than foreign products, laser radar, on the domestic unmanned developers, automotive technology companies upstream, automotive OEMs have great significance.

Reducing the hard threshold of unmanned research and development, in the test, research and development to expand the level of laser radar and other components of the market size and accelerate the birth of consumer products. In this path of industrialization of technological achievements, cheap multi-line laser radar is an important fuse. In addition to R & D, equipped with unmanned vehicles, RoboSense this product also contributed to the unmanned data-related industry progress. LIDAR is the eye of the unmanned vehicle, it can be said that the important data acquisition equipment. More cost-effective and more efficient sensors bring more data, which is of great help to unmanned data and algorithm research.

China has many software teams, whether Baidu, high German and other large Internet companies, or small and medium-sized technology business team, mostly from high-precision map and location-based services to cut into the unmanned industrial ecology. Innovation and entrepreneurship in this area is still a small minority, a big threshold is the cost of data collection is too high, while the data output services based on the cycle of income is still very long. Reducing the threshold for data collection is a huge boon for companies looking to build service and distribution capabilities in this area. And 500mw laser radar in this area, or an essential tool for R & D. There are many small and medium-sized R & D team is limited by resources can only hold the status of waiting for equipment, will be made with the multi-line laser radar greatly improved.

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