Enjoy life time everyday

2017年03月09日

Artificial Electromagnetic Materials

Artificial electromagnetic materials are material materials that control light in an unusual way at nanoscale. They can be used to develop foreign equipment such as invisible cloaks to quantum computers. But the problem is that the metamaterials they use usually contain metals that absorb energy from light and convert it into heat. As a result, a portion of the optical signal is wasted, reducing the efficiency of the device. A photonics laser research team led by Shaya Fainman, an electrical engineering professor at the University of California, San Diego, demonstrated the use of metallic materials that add excitation light to compensate for these optical losses, an optical semiconductor.

With the continuous development of laser technology and maturity, high powered laser pointer equipment has been widely used in all walks of life, such as laser marking machine, laser welding machine, laser drilling machine and laser cutting machine, etc., especially CNC burning laser pointer cutting machine Equipment, in the rapid development of the past few years, is widely used in sheet metal, metal products, steel structures, precision machinery, auto parts, glasses, jewelry, nameplate, advertising, crafts, electronics, toys, packaging and other industries. Cutting speed, cutting quality, high precision; slit narrow, smooth cutting surface, does not damage the workpiece; not affected by the shape of the workpiece, the workpiece is not affected by the shape of the workpiece, Saving materials, more effective cost savings; simple, safe, stable performance, improve the new products. In addition to the metal material processing, Development speed, with a wide range of adaptability and flexibility.

Laser marking machine advantages: laser beam mode is good, the electro-optical conversion efficiency, low power consumption, maintenance-free; some optoelectronic measurement equipment manufacturers measuring the laser light source from the initial He-Ne burning laser pen diode laser to obtain The best machine life (He-Ne laser life is generally 10 ^ 4HR, and diode laser life is 10 ^ 5HR, a difference of ten times), especially suitable for on-site long-time operation; instantly can achieve the role of switches, suitable for communication purposes.

The emergence of laser inkjet printer to a certain extent, shorten the gap between China and the developed countries in this area, but in order to really catch up with developed international, domestic enterprises must innovation, speed up technological reform. From the current customer demand, equipment maintenance rate is low, print speed, content, automatic cleaning easy, simple and quick operation will become the future development trend of Pen Maji a major trend. For the 5000mw green laser inkjet machine industry, in order to continue to grow and develop, we must take the international development path, and the international laser inkjet printer market synchronization, developed with independent intellectual property rights of new results, rapid access to R & D commercialization.

Encryption is an important part of modern life, so that sensitive information can be safely shared. In traditional encryption technology, the sender and receiver of a particular message determine the password, or the key, so only those who know the key can decrypt the information. But as computers become faster and more powerful, encryption passwords become easier to crack. Quantum cryptography guarantees "unbreakable" security by hiding information into light particles or photons emitted from the 3000mw laser pointer. In this cryptographic form, quantum mechanics is used to randomly generate a key. The sender, commonly known as Alice, sends the key by polarizing the different polarized photons. The receiver, commonly referred to as Bob, uses a photon detector to measure the polarization direction of the photon, and then the detector converts the photon into bit information, assuming that Bob uses the correct photon detector in the correct order, Get the key.

Laser cutting is a kind of high energy density controllable non-contact processing. It focuses the laser beam into a spot with a minimum diameter of less than 0.1mm, so that the power density at the focal point can exceed 107W to 108W / cm ~ 2. The irradiated material is quickly heated to the vaporization temperature and evaporated to form pores. As the 1000mw green laser beam moves relatively linearly with the material, the apertures are continuously formed with slits of about 0.1 mm in width. The cutting also adds auxiliary gas to the material to be cut to accelerate the melting of the material, blown away the slag or protecting the slits from being oxidized.  
タグ :laser pointer


Posted by laserman at 20:44 Comments(0) Technology

2017年02月28日

Current Status and Future Trend of Lidar

The earliest mature laser radar technology is used to detect ozone, sulfur dioxide, aerosols and other atmospheric detection of brightest laser pointer radar. In 2016, in the intersection of Temple 2 and Shenzhou 11, the use of laser radar in the two spacecraft docking process to measure the relative position, angle, etc., to ensure precision docking; and China launched Chang'e III, in the landing Used to scan the bottom of the landform, detection of obstacles, this is a terrain to detect the terrain of the lidar. In recent years, with the development of artificial intelligence, automatic driving, the rise of auxiliary driving, to promote the use of laser radar in the civilian field.

From the technical point of view, there are two main types of laser radar for civilian use:

The first is a multi-beam laser side by side rotation 360 °, each beam of laser scanning a plane. Early laser radar for the 64-line (that is, 64 laser), then has to meet the needs of automatic driving, but the cost of up to 70,000 US dollars, not accepted by the market. Later, in order to reduce costs, the company launched a 32-line, 16-line green astronomy laser radar. But the cost reduction is caused by the decline in resolution, which is easy in the vehicle driving process to detect obstacles when the blind spots, bringing security risks. The second is a solid-state lidar. This technology to the United States Quanergy Systems solid-state laser radar sensor S3, led by phased array scanning, is not commonly used mechanical scanning. It does not like the first technology will produce mechanical movement, can significantly reduce production costs. But the current technology is not mature, from the product market there is still some distance.

The biggest advantage of a lidar is that it provides distance information directly. Usually we see the photo or video is a plane, which is XY two-dimensional space, but the driver is most concerned about the distance, that is, Z coordinates, which belong to three-dimensional. The biggest selling point for automatic driving is that the accident rate of road driving can be reduced to zero. Because the automatic driving is controlled by the computer, if the system does not fail, then he will strictly abide by the traffic rules, will not appear God, drunk driving and so on. But once there is a problem, such as the previous Tesla event, it will cause a great blow to the automatic driving.

Semiconductor lasers have the greatest potential as light sources. Because the size of the semiconductor blue laser pointer can be very small, the cost is relatively low, in line with the requirements as a vehicle configuration. Now we see those who installed in the unmanned roof of the laser radar, such as Velodyne, the first is not designed for automatic driving, but the automatic driving just used some of these features, such as 360 ° scan. After real use, these should be integrated into the interior of the car, for example, integrated into the position of the lamp, the semiconductor laser happens to be able to meet this condition.

Strictly speaking, there is no laser radar on the market at the beginning of the birth is designed for automatic driving optimization design. China's many domestic laser radar manufacturers produce product shape and performance are imitating the United States Velodyne company's product design. However, Velodyne company early main audio business, after the technology upgrade, only the development of the burning laser radar technology LiDAR and fame. But some of its indicators beyond the requirements of ordinary cars, brought a high cost, and some of the necessary indicators have not been achieved. Since 2016 we are engaged in this direction of research, and with the end users and some owners to conduct extensive communication to understand their needs. We want to launch a laser radar that is optimized for automatic driving. In this way can save as much as possible to save, reduce costs, can not save the place, improve the indicators, improve safety.

Lidder's market is very large, and many colleagues are engaged in the field of research and development. In fact, the largest 3000mw green laser radar market is not the field of automatic driving, but in the service of the machine robot vision. Unmanned aerial vehicles, service robots, and some entertainment projects to capture distance from the sensor, these areas of the lidar market will be greater. At present, some domestic universities, research institutes and Baidu, Huawei and other large IT companies, production and research enterprises are in the study. Experts believe that the final product development model, or should follow the R & D, the client and the market, the three closely together, starting from the initial design, so that the product can be balanced to meet the needs of all parties to play its maximum value.  
タグ :laser pointer


Posted by laserman at 17:49 Comments(0) Technology

2017年02月25日

How does the carbon dioxide laser transition?

Carbon dioxide laser by C.Kumar N.Patel in 1964 in Bell Labs invention, is the photonics industry standard ancient technology. But despite its long history, CO2 laser technology continues to flourish with its unique wavelength, power and spectral purity, and continues to be used. Because many natural and synthetic materials have strong characteristic absorption over the 9-12 μm spectral range across CO2 high power laser pointer, there are many opportunities in material handling and spectral analysis. These wavelengths are also included in the important window of atmospheric transmission and are ideal for many sensing and ranging applications.

A typical CO2 laser consists of a large amount of gas discharge from a mixed CO2 molecule. Due to the very close to the energy level of molecular vibrations and rotations, the photons emitted between these energy levels have low energy and long wavelengths compared to visible and near infrared (NIR) light. Carbon dioxide lasers offer power levels from milliwatts to tens of kilowatts, ranging from small instruments to high power cutting. And because the CO2 laser has a very high spectral purity, with <1kHz radiation width and no power trade-off, conversion efficiency of up to 10%. These features enable CO2 burning laser pointer to address emerging applications such as material processing, photodetection and ranging (lidar), thermal visual aids, and targeted therapeutic medical applications.

In industrial applications, high-power fiber lasers offer higher efficiency and better metal absorption at lower cost. However, CO2 lasers are still the only choice for non-metallic materials that handle many NIR wavelengths that do not absorb fiber lasers. The quantum cascade laser is small in size and wavelengths can span 2-12μm, making it ideal for spectroscopy. However, in the long-wave infrared (LWIR) band of 8-12μm, many sensing and spectrally sensitive industrial and medical applications require high power, spectral purity, excellent coherence and stable spatial pattern combined with this requirement only CO2 The laser can be provided.

While CO2 lasers can solve all the industrial needs of the era is coming to an end, we are facing new materials and increasingly demanding industrial processes brought about by the challenges that require a deeper understanding of the true value proposition of the 10mw laser pointer, as well as the manufacture and sale of carbon dioxide lasers The different methods. In terms of manufacturing, this new paradigm closely matches the specific customer requirements using CO2 laser wide range specifications. In terms of marketing, from the original way of the average power pricing to customer-specific program pricing, such as pulse shaping, peak power, wavelength characteristics and operational stability to match the special materials and application requirements.

On the road to the expansion of Moore's Law, carbon dioxide lasers have been identified as the best tools for laser generation of plasma to produce extreme ultraviolet radiation. This 13.5 nm EUV light is produced by evaporating the molten droplets of tin. While testing other lasers for such applications, such as Nd: YAG lasers, the efficiency is not high for carbon dioxide lasers, because tin has a much higher reflectivity for CO2 laser lighting, so carbon dioxide 5mw green laser produce higher speed and better plasma properties Optical flow

The carbon dioxide laser is a reasonable way to adjust the optical device because its output beam is highly absorbed by the LIGO optics and it can provide high wavelength purity and power stability without increasing the noise to the measurement. However, according to LIGO specific specific application requirements, the development of single-wavelength stable CO2 laser, suitable for real-time adaptive system is very precise control loop, accurate offset optical distortion. When the optical element is insufficiently compensated for thermal deformation, the CO2 violet laser pointer beam is shaped as a ring to provide additional compensation (overtemperature correction), and if the optical element is over-compensated, the CO2 laser beam is shaped as a disk in the center of the optical element Compensation (under thermal correction).

The new multilayer plastic has a very strong absorption peak at a particular line in the CO2 spectrum, and even requires a laser to rapidly convert wavelengths from one layer to another during the cutting process. The replacement of a large knife-and-die system would require a laser array to produce almost no heat-affected area excision while tracking hundreds of feet per second of mobile web. This dedicated 1mw laser pointer requires a high accuracy at a single wavelength in the spectrum, with a potential high peak power of 100 to 1 or even higher for the average power ratio and a fast (> 10 kHz) pulse.

Traditionally, such peak power and fast pulses require Q-switches or other external modulation techniques that are too expensive for large-scale deployment of such industries. However, we are developing kilowatts of peak power for carbon dioxide, with no small form factor external modulation to meet these requirements. In fact, the latest trends in manufacturing, medicine, and materials science are forcing the value proposition of "dollar / watt" over the past half century to evolve into a customer-centric, customized era of CO2 lasers.

https://www.fluther.com/199056/remote-laser-processing-technology/

http://www.turf.fr/blogs/view/17023

http://laserman123456.seesaa.net/article/447323810.html  
タグ :laser pointer


Posted by laserman at 16:26 Comments(0) Technology

2017年02月20日

Laser Interferometer Gravitational Wave

The 30mw laser pointer interferometer gravitational wave observatory (LIGO) is one of the world's most sensitive instruments for the detection of spacetime ripples, and, according to some physicists, it is the best instrument for the production of gravitational waves. Although these gravitational waves are too weak to be detected, the researchers believe that in principle they can detect some strange quantum effects between macroscopic objects. A meeting last week, the American Institute of physics, from the California Institute of Technology Belinda Pang in a statement said: "we optimize the detection of gravitational waves on LIGO at the same time, also optimized the gravitational wave emission".

laser pointer

Einstein explained the origin of gravity in 1915: gravitational waves stretch the space itself. The mass of the earth, such as the earth, distorts the space around it, and the straight line of the free movement of the body is bent, which is equivalent to the force of gravity. Einstein predicted that when the two objects will also produce gravitational waves when rotating each other, and LIGO's more than 1000 physicists have been detected for the first time when the merger of the two large black hole when the gravitational waves emitted.

LIGO relies on its two extremely precise detectors, one in Washington, Hanford, and the other in Lewis,, Livingston. Each probe has a pair of 4 km long, mutually perpendicular sounding arms. The two arm is actually two detection ruler length change researchers by 300mw green laser can measure the two ruler, then detecting space stretching, and this change is extremely small, with such a long ruler are difficult to detect.

Two at the end of a long ruler is equipped with mirrors 40 kilograms, laser is reflected back and forth between the two mirror, when change one arm length, the laser will accordingly interfere to strengthen and weaken the interference. The researchers used this method, called interferometry, to get the length of the ruler. Gravitational waves are so weak that in order to detect it, the LIGO must be measured at a proton size of 1/10000.

But the high sensitivity of LIGO also suggests that it can produce gravitational waves efficiently. To prove this, Pang and her colleagues have created a quantum mechanical model to explain how the curvature of the space affects the 100mw laser pointer beam traveling back and forth in the probe arm.

In order to make the measurement as accurate as possible, LIGO physicist must ensure that wave crests and troughs - phase - maintain absolute stability. Subject to the uncertainty principle of quantum mechanics, the amplitude of light waves in this case will not be stable. The amplitude of the inevitable disturbance generates random force on the mirror, the mirror produces tiny movement which sparks space-time ripples, Pang said. Of course, the gravity waves generated by LIGO can be nothing compared to the gravity waves you throw out of a 200mw green laser bowling ball, but the efficiency is the best.

This conclusion is not surprising ", Beijing Normal University physicist Fan Zhang said," it is the nature of the detector and the gravitational wave coupling, once the coupling, the detection of gravitational waves and gravitational wave emission is one thing." Although weak enough to be directly observed, the gravitational waves generated by LIGO can still be used to probe the quantum effects of macroscopic objects, Pang said. The micro particle quantum mechanics (such as electrons) can also appear in the two place, many physicists have boldly speculated that perhaps we can make a burning lasers for sale macroscopic object (such as a mirror LIGO) in quantum state in a similar.

This microsecond state will not last long, the system will be affected by the influence of the outside world, the decoherence effect, which collapsed to a certain state. "However, we can get the speed of decoherence and compare it with the effects of gravitational waves," Pang said. Some physicists believe that gravity plays a special role in the collapse of quantum states of macroscopic objects.

"This is an interesting idea, but very challenging to strongest laser pointer implement," Pang partner and California Institute of Technology physicist Yiqui Ma said, "in order to see the effect of quantum gravitational waves, researchers must eliminate all other sources of decoherence." Pang agrees, "it's hard to believe," she said. "But only LIGO has the conditions to make it happen."

http://laserman.bcz.com/2017/02/17/laser-technology/

https://japaneseclass.jp/notes/open/2524

http://venturebeats.userecho.com/topics/1006-excimer-lasers/  
タグ :laser pointer


Posted by laserman at 19:16 Comments(0)