Thermal Processing - Capabilities
Flow Field Diagnostics -Diagnostics are extremely important for accurately verifying and benchmarking CFD calculations or particle behavior and understanding complex phenomena such as particle heating and in-flight oxidation. Critical variables such as temperature, velocity, entrained air fraction and concentrations of very reactive species like atomic oxygen are difficult to measure because of brief particle residence time (on the order of 1 ms), rapid heating, and the steep gradients in HVOF and plasma flow fields.
INL researchers use flow field visualization techniques such as pulsed laser schliren to obtain qualitative information on jet behavior and turbulence and quantitative information on jet spreading and laminar-to-turbulent transition. Enthalpy probes integrated with a mass spectrometer are used to obtain information on total entrained air fraction, and with the assumption of local thermodynamic equilibrium yield temperature and velocity information. High-resolution coherent Thomson laser scattering provides a direct measurement of gas temperature and very high-resolution measurement of the Doppler shift due to bulk gas movement provides gas velocity. Nonlinear spectroscopic techniques including Coherent-Anti-Stokes-Raman Spectroscopy (CARS) provide concentration and temperature of molecular species like oxygen and nitrogen. Atomic species concentrations are obtained by multiple-photon laser induced fluorescence (LIF).
Particle Diagnostics -Over a number of years, the INL has developed several particle diagnostic techniques applicable for scientific studies as well as routine coating fabrication. The most sophisticated of these techniques uses a laser based Phase Doppler Particle Analyzer (PDPA) to acquire simultaneous information on particle size and velocity. INL researchers developed sophisticated timing and logic circuitry to enhance the PDPA capabilities and integrated a high-speed two-color pyrometer system into the PDPA system design. A schematic of the instrument appears in Figure 1. Using this modified PDPA system, researchers can obtain temperature measurements and ensure that size, velocity and temperature data all originate with the same particle. This diagnostic technique is advantageous because particle size can be measured directly and independently of particle optical characteristics such as emissivity. However the assumption of spherical particles is implicit in the measurement. The diagnostic technique can also identify the velocity and diameter of "cold" particles (particles that are not hot enough to provide temperature information) through laser interrogation. In addition, size and velocity information can be obtained on particles that are entrained directly in the highly luminous hot regions of a plasma jet.
Closed Loop Process Control -Process control is an ongoing research and development effort at the INL. Plasma-spray processing is inherently complex because plasma-particle interactions can cause variations significant enough to limit process repeatability. Such variations occur in the particle-state from run-to-run and during long continuous depositions for large parts. The limited ability to maintain a narrow operating window precludes applications that require tight control of coating properties, and increases the complexity in developing new process recipes to achieve a specific set of coating performance objectives. INL’s strategy is to improve plasma spray processing controls through real time diagnostics. Such capability should improve yield, enable engineering capabilities to develop new coating structures, and reduced time and cost to market. We have developed diagnostics specifically for this purpose and have now implemented two generations of closed loop process controllers based on these measurements. We can directly monitor and control the process degrees of freedom such as particle velocity, temperature, and shape and trajectory of the spray pattern, that determine coating properties.
LAVA CFD Code - The ability to separate variables and examine the influence of each variable separately in a controlled manner is the primary advantage offered of computational treatments of highly complex phenomena such the plasma spray process. Computational tools can provide insight into phenomena that are either difficult to measure or that cannot be directly measured. Particle melt fraction shown in Figure 2, or the location of the melt or solidification fronts or the internal distributions of temperature in a particle are examples. The Lava CFD code was developed for this purpose. LAVA code is a greatly enhanced version of an earlier spray combustion model. LAVA solves the complete, time-dependent, compressible Navier-Stokes equations for a multi-component chemically reacting ideal gas with temperature dependent properties. The code is multi-dimensional including 2D, axisymmetric with swirl, and fully 3D geometry. Turbulent mixing is modeled using either a k-e or subscale grid turbulence model. A self-consistent ambipolar ion-electron diffusion model is included and the heavy particle temperature is allowed to differ from the electron temperature. The solution technique uses explicit finite difference numerics and a unique computationally efficient algorithm that handles the disparate time scales of mixed "fast" and "slow" chemistry has been implemented.
The particle model allows for multiple simultaneous injection locations and particle types. The stochastic injection model allows the user to specify the distribution of particle size and density, injection velocity, and injection direction in three space dimensions. Particles are modeled as discrete Lagrangian entities, which exchange momentum and energy with the plasma. A statistical approach is used to approximate particle dispersion by turbulent gas motion. The concept of a "computational particle" is employed, where each computational particle is representative of a group of similar real particles. Sampling from the specified distributions of particle properties stochastically generates computational particles. The particle behavior model now includes the calculation of temperature distribution and the location of the melt or solidification front in each particle. A mass transfer model accounts for both the effect of evaporation on plasma-particle heat transfer and allows for realistic estimation of mass loss at temperatures less than the particle boiling point. Heterogeneous surface chemical reactions, such as oxidation, and diffusion of oxygen or other chemical species into the particle have also been included.
Coating Characterization -Recent INL research efforts into physical characterization are focused on quantifying the mechanical properties (Young’s modulus, etc.) and residual stress state of coatings. The total stress state in a coating/substrate is comprised of the quench stress and the coefficient of thermal expansion (CTE) mismatch stress. The residual stress-state of a coating is experimentally determined by a laser-based coupon curvature measurement technique, Figure 3. The measurement technique is integrated with a vacuum furnace making it possible to evenly heat the substrate/coating unit without the effects of oxidation. Quench stress and thermal mismatch stress can be estimated by measuring the curvature at various temperatures between room temperature and the temperature of the substrate during deposition. Measuring the curvature as a function of temperature also permits direct calculation of the coating’s temperature CTE rather than relying on tabulated values for bulk material. This is particularly important because thermally sprayed material properties can vary greatly from those of a bulk material. Complementary work is addressing the experimental determination of the modulus and thermal transport properties of thermally sprayed materials. INL also employs the traditional suite of physical characterization methods involving optical or SEM examination of microstructure coating samples, measuring micro hardness, adhesion, and quantifying phase content and chemical composition using x-ray diffraction and XPS, Auger, etc.


A flexible and transparent fiber made by pulling strings of molten glass or plastic with a diameter slightly thicker than that of a human hair is called optical fiber or optical fibre depending on the English being used US or UK. Since inception optical fibers have been mostly used and designed as a medium to transmit light between the two ends of the fiber and this is the sole reason why they find wide usage in fiber-optic communications. Here they are used to transmit data signals over longer distances and at higher bandwidths compared to the conventional wire cables. Fibers have evolved as an alternative to metal wires because signals transmitted in them suffer less loss.
The most important advantage of using optical fibers is that they are immune to electromagnetic interference which is a huge problem with metal wires; all such important characteristics are well taught using our optical fiber training kits fibre optics trainer boards. An optical fiber is basically a solid core which is surrounded by a transparent cladding materiel with a lower refractive index than the core. The light travels in the core by using total internal reflection which makes the fiber behave like a wave guide.


Through innovative imaging algorithms and ground-breaking hardware, HABICO, Inc. seeks to revolutionize medical ultrasound imaging. Founded in Rochester, NY in early 2014, the company has been working closely with the University of Rochester on a next-generation breast imaging system that will offer unprecedented high fidelity, incomparable resolution, and heretofore unavailable clinical information. Combined with very fast imaging times, the novel breast imaging system promises dramatic improvement in detection and diagnosis of breast cancer.
Robert C. Waag
President and CEO
Jeffrey P. Astheimer
Vice President and CTO
Jason C. Tillett
Enlisting Supercomputers in the Fight Against Breast Cancer (11 February 2015)
Lance Farrell, International Science Grid This Week


Laser scanners for machine tools can quickly capture the complete surface data for a part while it is still clamped, bringing new levels of speed, precision and flexibility to machine tool inspection, while minimising the need for external measurement devices during the machining process.
The LS-C-5.8 enhances productivity by using laser scanning technology developed for coordinate measuring machines and portable measuring arms to capture the complete surface data for a part directly on machine tools.
The LS-R-4.8 wireless laser scanner that works automatically with a tool changer. Data is transmitted via radio to the machine control and measuring software, which is why the sensor can be changed in and out of the tool changer without any manual steps.
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ADT inverter in extractive industry
Application of AD series frequency converter in oilfield pumping unit
At present, the total number of pumping units in various oil fields in my country has exceeded 100,000, and they are the main energy-consuming equipment in each oil field. According to the capacity of each motor 30KW (actually more than that, 37KW and 45KW motors are used most in oil fields, and some 55KW and 75KW motors are used), the total installed capacity is more than 3 million kilowatts. As the most energy-consuming equipment used in oil field production, the load rate of the pumping unit drag motor is generally low, resulting in energy waste. In the actual production process, the pumping unit is affected by many objective factors such as the depth of the oil well, oil quality, impurities, sand content, water content and other objective factors. It is necessary to adjust the operation stroke and stroke, and even replace the motor and change the power of the motor; At the same time, due to the different geographic location and latitude of the oil field, and natural factors such as the climate in the area, it will also have an impact on the mining operation, requiring the pumping unit to adjust its speed according to the actual working conditions. In view of the above-mentioned technical requirements of the oil field pumping unit and the social benefits of its use, the basic requirements for the motor control system of the pumping unit are:
☆ A wide range, stable and reliable stepless speed regulation;
☆ It has a significant power saving effect.
1. Energy-saving control cabinet for variable frequency speed regulation
(1) A frequency converter with independent intellectual property rights developed and developed by Audite Electric Co., Ltd. The control object is an ordinary three-phase AC asynchronous motor, and the control accuracy reaches the control level of a synchronous servo motor. Wide speed range, high positioning accuracy, large low-speed torque, and complete software functions. This variable frequency speed regulation and energy-saving control cabinet combines the operating conditions of the pumping unit and the actual conditions of the oil well to timely and automatically adjust the motor's operating speed, acceleration, torque and other parameters, so that the original drive motor can be operated in a highly efficient and energy-saving state. jobs. Through the actual application in the oil field, it is proved that the frequency conversion speed regulation energy-saving control cabinet can carry out speed regulation operation simply and safely, which greatly reduces the work intensity of on-site operators, improves production efficiency, and achieves obvious energy-saving effects.
(2) Features of frequency conversion speed regulation energy-saving control cabinet
The frequency conversion speed regulation energy-saving control cabinet has the following characteristics:
1. AC-DC-AC main circuit
First, the input three-phase 50Hz alternating current is converted into direct current, and then it is inverted into a three-phase alternating current with adjustable frequency and voltage effective value to supply the drag motor.
2. A wide range of speed control
The speed of the motor can be controlled accurately and in a wide range. The speed control range is 0-1500r.p.m, and the speed control accuracy is 0.3r.p.m.
3. Overload capacity of three times rated torque
It has a constant torque output characteristic in the range of zero to rated speed, and has an overload capacity of 3 times the rated torque. Therefore, at a very low speed, the motor can also output rated torque and has a 300% overload capacity.
4. Control characteristics of low speed and large torque
In the process of starting the pumping unit motor, it can drive the motor to output enough torque. Thus, in the process of increasing the speed from 0 to the set value, the current is stabilized and a true "soft start" is realized.
5. Speed control of slow down and fast up
Through the decoupling and independent control of speed and torque, the speed control of the pumping stroke from slow to higher is realized.
6. With internal soft PLC function, it can detect and control the torque.
(3) Advantages of frequency conversion speed regulation and energy-saving control cabinet
According to the analysis of the design principles, control characteristics and application examples of the AD series of frequency conversion energy-saving control cabinets, the oilfield pumping unit is equipped with the Deruis series of frequency conversion energy-saving control cabinets, which has the following advantages:
1. Easy to adjust speed
As the AD series AD series frequency conversion speed regulation energy-saving control cabinet has the characteristics of large range and continuous speed regulation, it only needs to adjust a knob to realize continuous and stable speed regulation function to meet the requirements of pumping unit adjustment strokes. For on-site operators, the operation is extremely simple.
2. Reduce work intensity
The use of Aodete AD series frequency conversion energy-saving control cabinet for speed control is easy to operate, and there is no need to change the mechanical structure of the pumping unit and supporting equipment during the operation, which greatly reduces the work intensity of the workers on site.
3. Improve production
ADT frequency inverter is applied to diamond wire saw(Diamond beads saw)
i Industry introduction:
Diamond wire saw (machine), also known as diamond beads saw, is the most advanced stone mining equipment, and has been widely used in the stone industry, machinery industry and construction. It is mainly used for the mining and processing of stone, the demolition and repairing of concrete buildings, the processing of brittle and hard materials such as glass.
ii The working principle:
The diamond wire sawing machine consists of main motion system, feed system, diamond beads saw, tensioning device, guiding mechanism, control system, and cooling system etc. The diamond wire sawing is jointly done by a diamond beads rope which directly involved in cutting and a mechanical device that drives the beaded rope movement. Before processing, a piece of beaded ropes are jointed end to end with copper tube casing forming a saw wire loop. During processing, the closed-loop bead rope tensioned on the wire guide set of the wire saw is driven to move at high speed, and the cutting is realized by the grinding motion of the bead. The diamond wire saw is divided into four series according to the cutting object: concrete cutting series, marble cutting series, granite cutting series and heterogeneous cutting series.
III Techniques requirements
The diamond wire sawing machine uses the main motor to drive the sawing rope to run along the track. The sawing rope passes through the drilled hole on the surface to be cut, and the main motor drives the whole sawing machine moving forward along the cutting face with a certain speed through the reducer. The saw rope speed must be adjusted according to the load condition of the main motor and the tension required by the saw rope. If the moving speed is too fast, the load of the main motor increases rapidly, and even overload. And the tension of the saw rope also increases rapidly. The saw wire will be broken if the speed is not adjusted timely. If the moving speed is too slow, the sawing wire tension is drastically reduced, the saw rope will slip on the stone, the cutting efficiency will be reduced, and the slack rope will be twisted to break the saw rope. The key to improve the sawing machine cutting efficiency is to make sure the main motor load balance and sawing wire tension proper.
Due to the irregular shape of the mine or rock, the cross-section is naturally large and small, and the moving speed of the sawing machine must be adjusted in time.
iv the application case
1) electrical configuration:
Main motor: 45KW, 380VAC, 8-poles, rated speed 740 rpm, Current 96A
Feed motor: 1.5KW, 380VAC, 4-poles, variable frequency motor
Main motor frequency inverter: AD300 series, T4, 45KW
Feed motor frequency inverter: AD300 series, T4, 1.5KW
2) Technical plan:
Main motor VFD output the main motor running current from AO1 to the feed motor inverter’s AI2 as the PID feedback value. PID works as auxiliary frequency reference. External potentiometer is taken as the main frequency reference via AI1. The added value of main frequency and auxiliary frequency is output to the feed motor. The feed motor speed will change according to the PID feedback from the main motor real-time current. This keeps the main motor runs at constant current. The main motor frequency inverter’s frequency reference is set by external potentiometer. The advantage of this solution is that the load control is stable and precise. The feed speed freely adapt to the cross-section load change, system fluctuation is small and cutting efficiency is higher.
iii Inverter wiring diagram:
IV AD300 frequency inverter control features in diamond beads saw
1) the vector control method is adopted to improve the response speed and accuracy of the sawing machine.
2)The low frequency torque is large, and the acceleration and deceleration time is short, which improves the cutting efficiency for customer.
3) The inverter has strong overload capability, which avoids the trip-off in case of high instantaneous transient current when cutting the work piece.
4) The carrier frequency adjustment range is wide, which reduces motor noise and improves the working environment of workers.
5) the circuit board is coated with conformal coating made in Germany, so that the inverter can still run stably under the harsh environment of wet and dusty mine.
The diamond wire sawing machine has been widely used in the stone industry. The diamond wire sawing machine with VFD control is used to extract stone and process various shapes of stone plates (mainly heterogeneous plates), which has the advantages of high production efficiency, good product quality and low cost. It embodies the new development of modern industrial production technology. It is of great significance to obtain high-quality raw materials and various shapes of plates, and also significant to improve he processing quality, production efficiency and economic benefits.


Data logger for pressure and temperature
The new and fully contact-free data logger "Patbox" from Witt: a highly mobile solution for measuring pressure and temperature rapidly and accurately everywhere in food processing packaging and other packaging production.
3D-Animation for electronic gas mixer KM-MEM+
Take a look inside the ›› KM-MEM+ and get to know its functionality and how it benefits your production. Get to know our top-performing gas mixer:Read more


Nowadays, automatic labeling machines are very common in today's society. In fact, the automatic labeling machine we are talking about here is different from the manual labeling machine or the hand-held labeling machine. The handheld labeling machine is relatively cheap, probably Just a few hundred dollars, the price tag of small supermarkets can be regarded as a way. In many cases, it is necessary to hold the machine to achieve the labeling action. Relatively speaking, the role of the automatic labeling machine is very big, below Let's understand:
The automatic labeling machine can be configured according to the application. If it is used for stand-alone use, then the product needs to be manually placed and received manually, but the speed is much faster than the semi-automatic speed. For faster work efficiency, discharge and receiving The mechanism can be equipped with a material handling mechanism, and the automatic labeling machine can be used for wiring. It can improve efficiency. It can be placed at the back end of the filling machine and the cartoning machine. The front end equipment is automatically transported to the labeling machine after work, without manual operation. The automatic labeling machine can be used for single machine or with assembly line. It can realize various labeling functions on one machine. It is fully automated and more scalable than semi-automatic labeling machine. It has large output and high requirements. In the production environment of the production line, it is highly recommended to purchase automatic labeling machine equipment.
Contact: Wendy Jiang
Add: No.88 Huangcheng North Road, Fengxian, Shanghai,China


We hold over 10 sets of testing equipment.
This spectrometer is imported from the United States. It can test metallic materials.
This microscope can analyze the microstructure of drill rods, core barrels and other metal products.
Our operator is using a coordinate measuring machine to measure the diameter and depth of our products.
This vision measuring system is used to measure the size of holes and the overall dimension of various parts.
The synthetic diamond we use is all purchased from British or American brands, including Element Six and other renowned brands.
This microscope can magnify 500 times. It is used to test the composition of the synthetic diamond.
The compressive strength of the diamond is being tested by our machine.
Wuxi Geotec Geological Equipment Co., Ltd. Add.: No.113,Jiao Shan Road,Yangjian Machinery Industrial Park,Xishan,Wuxi,Jiangsu, 214107, China Tel.: +86-510-88552380 Fax: +86-510-88552380 +86-510-88552788


The latest news from academia, regulators
research labs and other things of interest
Posted: Feb 14, 2011
Dolomite Facilitates Control Over Internal Temperatures of Microfluidic Systems
(Nanowerk News) Dolomite, a world leader in microfluidic design and manufacture, has expanded its range of temperature control systems introducing the Hotplate Adaptor – Chip Holder H which allows control over internal temperatures of microfluidic chips without any disruptions to the fluid flow.
The use of temperature control systems is vital for many applications including nanostructure generation, controlled microreactions, and droplet microfluidics where droplets can be kept at certain temperature to prevent a solidification reaction until the droplets have left the chip.
Holding a microfluidic chip securely in position, the Hotplate Adaptor enables users to pre-heat or post-heat fluids by using the integrated tube heater. Operating over a wide temperature range up to 100°C, the adaptor is supplied with a removable lid that can be closed to maintain the chip at constant temperatures which is important for cell-based analytical studies to maintain cell viability. A glass viewing window (22mm in diameter) facilitates microscopic observations.
Quick and easy to use, the Hotplate Adaptor has been specifically developed for the Chip Interface H, and is compatible with Dolomite's Linear Connector 4-way, 1.6mm tubing and microfluidic chips that have a footprint of 22.5mm x 15mm.
For further information on Dolomite's range of temperature control systems and the complete portfolio of microfluidic products including connectors/interconnects, pumps, valves and pressure/flow rate sensors as well as custom devices please visit www.dolomite-microfluidics.com
The Dolomite Centre Limited
Established in 2005 as the world's first Microfluidic Application Centre, Dolomite focused on working with customers to turn their concepts for microfluidic applications into reality. Today, Dolomite is the world leader in solving microfluidic problems. With offices in the UK and US and distributors throughout the rest of the world, its clients range from universities developing leading-edge analytical equipment, to manufacturers of chemical, life sciences and clinical diagnostics systems.
Dolomite is pioneering the use of microfluidic devices for small-scale fluid control and analysis, enabling manufacturers to develop more compact, cost-effective and powerful instruments. By combining specialist glass, quartz and ceramic technologies with knowledge of high performance microfluidics, Dolomite is able to provide solutions for a broad range of application areas including environmental monitoring, clinical diagnostics, food and beverage, nuclear, agriculture, petrochemical, cosmetics, pharmaceuticals and chemicals. Furthermore Dolomite's in-house micro-fabrication facilities that include clean rooms and precision glass processing facilities allow to prototype and test all solutions rapidly which ensures a faster development cycle and reduces the time to market.
For more information please visit www.dolomite-microfluidics.com.


In the field of switching power supply technology, people are developing related power electronic devices and switching frequency conversion technology. The two promote each other to promote the switching power supply to light, small, thin, low noise, high reliability, with a growth rate of more than two digits every year. The direction of anti-interference development. Today we will mainly understand what a switching power supply is.
Switching power supply, also known as switching power supply, switching converter, is a high-frequency electric energy conversion device, which is a kind of power supply. Its function is to convert a level of voltage into the voltage or current required by the user through different forms of architecture.
The input of the switching power supply is mostly AC power (such as mains) or DC power, and the output is mostly equipment that requires DC power, such as a personal computer, and the switching power supply performs voltage and current conversion between the two.
The switching power supply is different from the linear power supply. Most of the switching transistors used in the switching power supply switch between the fully open mode and the fully closed mode. Both modes have the characteristics of low dissipation, and the conversion between switching will have higher consumption. But the time is very short, so it saves energy and generates less waste heat.
Ideally, the switching power supply itself does not consume power. Voltage regulation is achieved by adjusting the time when the transistor is turned on and off. On the contrary, in the process of linear power supply generating output voltage, the transistor works in the amplifying area, and it also consumes electric energy.
The high conversion efficiency of the switching power supply is one of its advantages, and because the switching power supply has a high operating frequency, a small size and light weight transformer can be used, so the switching power supply will be smaller in size and lighter than the linear power supply.
If the high efficiency, volume and weight of the power supply are the key considerations, the switching power supply is better than the linear power supply. However, the switching power supply is more complicated, and the internal transistor will switch frequently. If the switching current has not been processed, noise and electromagnetic interference may be generated to affect other equipment, and if the switching power supply is not specially designed, the power factor of the power supply may not be high.
The main purpose
Switching power supply products are widely used in industrial automation control, military equipment, scientific research equipment, LED lighting, industrial control equipment, communication equipment, power equipment, instrumentation, medical equipment, semiconductor refrigeration and heating, air purifiers, electronic refrigerators, liquid crystal displays, LED Lighting, communication equipment, audio-visual products, security monitoring, LED light strips, computer cases, digital products and instruments and other fields.
The continuous innovation of power electronics technology gives the switching power supply industry a broad development prospect. If you don’t know about the introduction of switching power supply, you can contact us. If you need the product, you can visit our website.


Boston—Cambridge Viscosity today announced that a U.S.-based industrial enzymes developer has purchased a ViscoLab 4000 viscometer. The company plans to use the small sample viscometer to monitor viscosity in enzyme and protein formulations.
An R&D representative from the company said they chose the ViscoLab 4000 because it is easy to use and meets their need for small sample sizes. “The sensor is very easy to operate. You simply drop the piston into the chamber and you get a viscosity reading. There is no need to reset the parameters for each assay.” Requiring less than 2 ml of sample, the viscometer will help to conserve sample and labor time associated with preparing the sample materials. “The new viscometer will allow us to monitor viscosity quickly, while using smaller amounts of sample material,” he said.
The ViscoLab 4000 supports up to 12 viscosity ranges and up to 10,000 cP, while providing accurate measurements at near-ambient temperatures. It features sophisticated electronics that allow users to define temperature/viscosity display units, data averaging interval and density. The small sample viscometer is particularly well suited for life science and pharmaceutical applications such as siRNA , drug development, protein formulation and delivery studies.
About Cambridge Viscosity
Cambridge Viscosity, the leader in small sample viscosity systems, provides automated viscometers used in life science applications to optimize product and process performance. Cambridge lab and process viscometers use the same core technology and are fully compliant with ASTM D7483. Cambridge instruments are compact, require small amounts of sample, incorporate temperature sensors and are extremely accurate, repeatable and robust. Cambridge's global reach provides application engineering support and service wherever and whenever needed.


Assessment of the quality of bottled water marketed in Addis Ababa, Ethiopia
The consumption of bottled drinking water has been increasing in the world. But, the quality of bottled water used for human consumption is not subjected to any stringent quality control measure in Ethiopia. The present study was carried out to determine the physicochemical quality parameters of twenty brands of bottled drinking water available in Addis Ababa and to compare with drinking water guidelines set by World Health Organization (WHO) and Compulsory Ethiopia Standards (CES). The samples were collected by random sampling technique. The physicochemical parameters such as pH; TDS and EC; total alkalinity, total hardness, HCO3-, Cl-; SO42-, NO3-, NO2-, F-) and common cations (Ca2+, Mg2+, Na+, and K+) were determined by pH meter, conductivity meter, titration, UV-Visible spectrometry, fluoride ion selective electrode and microwave plasma-atomic emission spectrometry, respectively. The mean physicochemical concentration of TDS, total alkalinity, total hardness, HCO3-, SO42-, NO3-, NO2-, F-, Cl-, Ca2+, Mg2+, Na+, K+, pH and EC in bottled water samples were found in the range (4.67-139), (12-165), (4-97), (16.3-202 ), (0.05-3.84), (0.02-0.84), (0.08-0.28), (0.03-1.26), (4.28-20.8), (0.19‑8.9), (0.02‑2.5), (1.8‑24.5), (0.14‑8.08 mg/L), (6.43-7.69) and (9.8-289 µs/cm), respectively. The drinking water quality index (WQI) was calculated based on 15 important quality parameters and the results were found in the range 3.85-49.2. The mean concentrations of physicochemical parameters in almost all the bottled drinking water were below the permissible limit set by WHO and CES. Hence, all the tested bottled water samples are safe for drinking purpose.
KEY WORDS: Bottled water, Common cations, Common anions, Physicochemical parameters, Water quality index
Bull. Chem. Soc. Ethiop. 2019, 33(1), 21-41


Here, the method is used to create a high-resolution 3-D electron microscopy reconstruction of aluminum nanoparticles, aiding efforts to design nanocomposites for applications ranging from fuel cells to transparent coatings. (Purdue University, U.S. Air Force Research Laboratory and Carnegie Mellon University)
Researchers are improving the performance of technologies ranging from medical CT scanners to digital cameras using a system of models to extract specific information from huge collections of data and then reconstructing images like a jigsaw puzzle.
The new approach is called model-based iterative reconstruction, or MBIR.
Read the full story.


Give away medical masks when you place an order. learn more
ams AG (austriamicrosystems AG) delivers many sensor types and capabilities with a focus on reliability, precision, accuracy and power consumption.
Analog and digital ambient light sensors (ALS) play a key role in controlling backlighting in LCD displays used in portable electronics.
Backlit displays have become ubiquitous, wherever you go today you see them, and judging the product primarily on the merits of its display.


Infrared Thermography Services
Electric Supply offers Infrared Thermography for commercial and industrial customers. Bob Jarding, Senior Vice President states, "Electric Supply can offer studies of electrical equipment using the Fluke infrared thermograpy system." The equipment used is the latest technology and our technicians are trained by Snell infrared. The technicians are Level 1 certified and have passed the testing to achieve this honor. The use of infrared thermography can help prevent and melt down or failure of electrical equipment. Scheduled repairs are less costly and do not disrupt production. The risk of failure or damage to plant or personnel is greatly reduced.
Information is up-to-date: 17.08.2016
Unbelievable price on Infrared Thermography Services in Sioux Falls (USA) company Electric Supply Co, Inc..


Silver Sintering is an exciting new technology that has captured the interest of our customers this year. We are now representing Boschman Technologies – a company with a reputation for innovation which specializes in the development and supply of advanced Film-Assisted Molding (FAM) and Sintering Systems for electronic assembly industries across the globe. Boschman has been a high-end niche player within the semiconductor packaging equipment industry since 1987.
Going to SEMICON West??
Meet the folks from Boschman at SEMICON West in San Francisco on July 10th through 12th. Stop by BOOTH #6156 and learn more about their Sintering Systems directly from the experts.
Boschman’s Advanced Sintering Systems
Silver Sintering is a new die attach technology offering a void-free and strong bond with high thermal and electrical conductivity – resulting in high yield and high reliability. Boschman’s systems can sinter a wide range of different devices including LED, power, IGBT, GFN, clip/heatsinks, thyristor and custom-designed power module devices. Their unique high-precision dynamic-insert pressure-control technologies allow you to sinter multiple dies with different die thicknesses resulting in controlled and predictable bond strength.
Boschman’s systems include:
SINTERSTAR Inline-F-XL / Inline F-XL-HC / Auto-F-XL-HC
Boschman’s fully automatic Ag Sintering Systems offer the absolute highest throughput available on the market and the largest sinter area, coupled with precise process control and monitoring.
- Largest sinter area – 350 x 270 mm
- Systems can be equipped with a large variety of sintering tool concepts
- The Inline-F-XL is an economic sinter system designed to fit into your automated assembly line
- The fully-automatic Inline-F-XL-HC can be integrated into your automated assembly line and is equipped with preheating and cooling stations
- The fully automated and stand-alone Auto-F-XL-HC works from cassette input to cassette output and is equipped with preheating and cooling stations
The most universal semi-automatic sintering system for all your green, lead-free die attach technologies.
- Sinters a wide range of different devices including led, power, IGBT, QFN, clip/heatsinks, thyristor and custom designed power module devices
- The Sinterstar Innovate-F-XL offers the largest sinter area (350 x 270 mm) and precise temperature control up to 320 C
- Top film protection
Ag Sintering requires highly-customized tooling solutions. Boschman offers a wide range of Sintertool solutions that fit on all of their sintering systems. The core technology is dynamic insert technology (patented) which provides flexibility and maximum control.
- The sintering pressure is precisely controlled and monitored during the complete sintering process and is programmable via the MMI (man-machine-interface)
- Dynamic controlled inserts automatically compensate for die height differences, resulting in a controlled and predictable sinter force
To read more about the reliability of Ag-Sintering Bonding Technology, click here to read our prior post.
Contact us today to learn more about Boschman’s Silver Sintering Systems.
Call Kevin Hartsoe at (215) 355-2460.


PIC Gauge™ - The Gates Parts Image Capture (PIC) Gauge belt wear app delivers an accurate measurement and evaluation of serpentine belt wear, all in the form of a simple smartphone app.
PIC Gauge utilizes a photograph taken with the smartphone’s built-in camera, and is analyzed by patent-pending software. The app is simple to use, and the results are immediate. Results can also be stored and retrieved for future reference. PIC Gauge is the first digital tool designed to be used by professional technicians, service writers, and do-it-yourselfers.


Air film damping plays a significant part in the design of micro electro mechanical devices. If a stationary surface is placed in close proximity to a cantilever, the air in between the cantilever and the surface will be squeezed when the beam moves towards the surface developing a pressure gradient across the width of the beam. This will push the air out of the gap. Alternately, when the cantilever moves away from the surface, the pressure in the gap is reduced and air flows into the gap. The work done in this process would reduce the energy of the cantilever and thereby the air acts as a damper and the process is called squeeze film damping.
Forces on the moving cantilever from gas film can be obtained from linearized Reynolds equation. The coefficient of damping force can be calculated from this provided the oscillating frequency of the cantilever is low and the pressure is near ambient. The damping ratio is calculated from it. This design form can be used to estimate the damping ratio for the first mode of vibration of the cantilever which is up and down displacement. The quality factor is calculated from the damping ratio for slight damping.
The plot shows the variation of damping ratio with the air gap thickness. Using the crosshair tool, the damping ratio for any air gap thickness upto 20µm can be estimated. It can be used to calculate the air gap that would give a damping ratio of 0.7 for optimum damping of a harmonically forced vibration.


Discontinued – please click here to view replacement.
TH7102 Series Thermal Camera
- Temperature measuring range
TH7102MX: -20 to 250 (STD), 100 to 2000 (option)
TH7102WX: -40 to 500 (STD), 200 to 2000 (option)
- Spatial filter
Smoothing outline of image for better image quality, ideal when using zoom facility
- Uncooled Focal Plane Array
320 ~ 240 microbolometer UFPA detector.
- Voice recording
Simultaneous recording of thermal image and Voice data
- Long wavelength operation, less affected by sunlight. 8 to 14µm band wavelength is less susceptible to
solar radiation thus preventing measurement errors
- Dust/splash-proof construction (IP54)
- Accurate measurement
Temperature resolution: 0.08
Measurement accuracy: %RFS
Frame time: 1/7.5, 1/30, 1/60 sec.
- 10-point temperature display and emissivity correction
- Ease of use – full automatic functions
Full auto (level, sense and focus) or individual autofocus, auto level and auto sense.
- Alarm function
Alarms at upper or lower limit
- Auto Gain Control
Automatically adjusts level or level & sense by tracing temperature of object to be measured
- Easy-to-carry compact and light weight body
Body weight 1.6kg, built-in compact battery 90g
- T display
Displays temperature difference between reference point and target point
- Real-time memory (option)
Automatically store images with selectable time interval (1/15 sec. to 60 min.) up to 832 images.
- Peak hold
Displays the Max/Min temperature during the recording cycle.
- RS232C and GP-IB interface are provided as standard
- Box setting
Displays Max/Min temperature in 5 areas
- IEEE1394 interface (option)
Possible to transfer images to PC in real time.


We offer three trigger modules designed for OEM applications. All are entirely solid-state designs that are compatible with virtually all commercially-available trigger transformers from Excelitas, E2V Technologies, Hyacinth Technologies, etc. We also offer our own TR-91 proprietary trigger transformer that features very fast rise time (<360 ns), high voltage output (>40 kV), and exceptional isolation (50 kV). The trigger transformer is connected to a terminal block on the module. (Trigger transformers sold separately.)
Models are available with different power supply requirements. All are capable of 25-50 Hz repetition rates (tranformer dependent), while the PG-108HP module is capable of continuous operation at 200 Hz and intermittent operation to 500 Hz. The model suffix denotes the maximum drive voltage and variants are available up to 1500 V. Modules are supplied as a self-contained printed circuit board with high-voltage charging supply, capacitive energy store, IGBT switch, and various input/output options. An external command signal fires the pulser and both electrical and fiber-optic inputs are available. Our trigger modules are tailored to the exact trigger transformer for optimal performance. When integrated with our trigatron switches in a carefully designed system, these modules can achieve a timing jitter of <10 ns. Further information is available from the following data sheets:
Pricing for OEM trigger modules and transformers is by quotation only and attractive discounts are available for quantity (>5) purchases. Specifications are subject to change without notice. Inquiries for additional product information are welcome!
Last revision: Wed, 21 Dec 2016 10:04:40 -0500


Since 5 May 2020, Chinese and Indian troops have engaged in aggressive melee, face-offs, and skirmishes at locations along the Tibet-Indian border. The standoff is now 160 days old and the trust factor between Indian armed forces and the Chinese people’s liberation army is below absolute zero. Thus, monitoring and tracking the adversary day and night becomes crucial.
As we all know Ladakh is mountainous terrain and keeping an eye over the adversaries is quite a challenging job for our soldiers. An advanced imaging system for monitoring and tracking the movement becomes not just crucial but of paramount importance. One such system is “T-rex” from the house of Tonbo imaging, this can help India track PLA 24X7 and be prepared for whatever nasty surprise the adversary plans for. As these systems can clearly distinguish between different objects and humans, it will easy for soldiers to find out the threat and act according to it.
Tonbo Imaging is a start-up based out of Bangalore. These guys design and develop sensing solutions that can see beyond the range of human eyes, with precision. They serve many industries including defence, consumer, industrial, and OEM. In the defence sector, their products range from tactical, Aerial, naval to homeland security, and command control. Let’s discuss a particular system named T-Rex which is a long-range reconnaissance and observation system.
T-Rex is an advanced long-range reconnaissance and surveillance system which includes a long-range day optical image sensor and a cooled area scan thermal imaging sensor included with a safe laser range finder which has a range of 20 km. This is also equipped with advanced algorithms that can perform intrusion detection and can also act as a long-range passive IR search and tracking system.
T-Rex deployed in Ladakh
This system has a long list of capabilities along with the above-listed features. Let’s take a look at the sensors first.
1) Cooled MWR thermal imager
2) Long-range low lux day imager
3) Long-range laser range finder
5) Digital magnetic compass
Now let’s take a look at the software features this system possess.
1) Image enhancement
2) Multi-sensor fusion
3) Electronic stabilization
4) Video tracking
5) Geo pointing and Georeferencing
6) Gyro sensor stabilized PAN/TILT functions.
Long-range low lux imager
The long-range low lux camera comes with a high resolution of 1/2” CCD (Charged coupled camera), an optical zoom of up to 120x which is really good for a system like this one.
IR imager included in this particular system has 15x continuous optical zoom capability for the IR optics with high image resolution with a spectrum wavelength of 3-5 µm and a 10x optical zoom for the IR imager.
Laser range finder
The laser range finder included in this system comes with a range of 20 km along with a high penetration rate and with high accuracy of +/- 5m.
Integrated GPS and DMC
The integrated GPS system comes with a CEP (Circular error probability) of 3m. This system also comes with three modes, which can be customized according to the requirement such as
1) Indian grid reference system
2) Military grid reference system
Apart from all the above features, the hinges of this system were designed to be very robust and this system can survive harsh weather conditions such as snowfall, heavy rain, hail storms and high-speed winds. This system also comes equipped with an auto tracker and radar slew to cue. This system also offers Mil-Std 810G protection.
Range and detection capabilities
Lastly, I would like to express my feelings regarding this particular product. It is a matter of pride for me as an Indian that Indian start-ups are doing such a great job in bringing in such advanced systems to be used by our armed forces. Though there are many start-ups making great products, this particular system impressed me quite a lot. I would like to conclude by sharing a fact that most of you won’t know that is this system is currently the best imaging system in the world.


The Aquatic Geochemistry laboratory maintains and operates the instruments shown below, dedicated to water quality analysis. For instance, we measure dissolved organic and inorganic carbon (DOC, DIC), dissolved sulphides (HS-) and polysulfides (Sn), ammonium (NH4+), and soluble reactive phosphorus (SRP). We measure dissolved trace elements such as rare earths and metalloids using a an Agilent triple quadrupole ICP-MS. Finally, we rely on shared facility for solid-phase work, including a LabConco freeze-dryer, a CEM Mars-5 preparation microwave, and a Flash 2000 CHN analyzer.
Our 80 m2 lab is fully equipped with the precise tools needed for trace-clean sediment and water chemistry work, including work in anaerobic conditions.


Nikon 8397 ACULON Laser Rangefinder Review
Looking for the best and most reliable laser rangefinder for your outdoor activity? Look no more, for the Nikon 8397 ACULON Laser Rangefinder is finally here! This cutting-edge laser rangefinder features portability and functionality in one product!
This Laser Rangefinder has a compact structure, allowing it to weigh as light as 4.4oz. It offers a clear and crisp view, and can deliver a precise reading even as far as 550 yards. Also, this laser rangefinder is user-friendly, super handy, and can be used for lots of purposes. Whether it is for hunting, shooting or golfing purposes, this Rangefinder has got you covered!
Nikon 8397 ACULON Laser Rangefinder Features
Optimum Quality and Portability
When doing outdoor activities, it’s best to have a laser rangefinder that is handy and easy to store. Therefore, you’ll never go wrong with this Nikon 8397 ACULON Laser Rangefinder as it is very compact and light, having 3.6” x 2.9” x 1.5” dimensions and a 4.4-ounce weight.
Aside from its optimum portable and lightweight built, this laser rangefinder is also made with optimum quality. So, rest assured you can make use of this rangefinder in your outdoor activities for a long period of time.
This Rangefinder has the ability to deliver speedy and reliable accuracy from 6 yards to the maximum covered distance of 550 yards. It displays distance in 1 yard or meter increments. Also, you can get the reading in an instant once you press the button!
Therefore, by using this Rangefinder, no second is wasted and you can maximize your time hunting, shooting, hunting or generally doing other fun activities in the outdoors.
Clear and Remarkable Quality Optics
One essential feature we are all looking for in a laser rangefinder is clear and remarkable quality optics. Since a rangefinder that has this feature allows us to see the target in a clear and crisp image quality, it makes the purchase as well as the experience worth it!
By having this Rangefinder, guaranteed you can get clear and remarkable quality optics in every view. This rangefinder is made with multi-layer coated optics, 20mm objective lens and a 6x magnification. Therefore, you can best see the target even at a maximum distance and especially at good lighting conditions.
Cutting-Edge Distant Target Priority Mode
In outdoor activities such as hunting or shooting, aiming the target accurately is the main point of having a laser rangefinder. Therefore, this Rangefinder will not disappoint you, as it takes target accuracy at a next level.
This Rangefinder has a cutting-edge Distant Target Priority Mode built-in program that lets you see the range of the farthest target among the targets measured. This enables you to accurately measure the farthest object currently targeted, even though it is partially covered by bushes and grass.
User-Friendly Structure and Display
By having this ACULON Laser Rangefinder, rest assured you will not have a hard time figuring out how to use it, as it has a user-friendly structure and display. This laser rangefinder’s LCD display offers easy, comfortable and clutter-free viewing. It runs under a single button operation, and it has a long eye relief for easy and strain-free viewing.
Also, this Rangefinder automatically turns off after 8-30 seconds of idleness. Therefore, you can save its battery for a longer, worry-free outdoor use.
Reliably Rain-Proof and Water-Resistant
The outdoors is certainly the most unpredictable area to be in! The weather report might say that it’s going to be a sunny day, and suddenly, it rains! Therefore, being prepared for this unanticipated weather change is a must.
This Rangefinder helps you get prepared as it is reliably rain-proof and water resistant. So, if your rangefinder gets wet, there’s nothing to worry about as it remains safe, 100% functional and intact.
- This laser rangefinder is incredibly handy and portable.
- It is durable and reliable to use, as it is made with quality materials.
- It offers a speedy accuracy as far as 550 yards.
- This rangefinder offers clear, crisp and quality optics.
- It is easy to view, user-friendly and water-resistant.
- This laser rangefinder could be quite small and uncomfortable to use for people with big hands.
- It is quite difficult to hold stable on a focused target.
- This laser rangefinder does not have a slope adjustment feature.
- Optimum portability (3.6-inch x 2.9-inch x 1.5-inch dimensions at 4.4oz weight)
- Speedy and accurate distance delivery
- 550-yard maximum distance coverage
- Distant target focusing accuracy
- Clear, crisp and quality optics
- User-friendly built, controls and display
- Extensive eye relief
- The best laser rangefinder at the best price
Frequently Asked Questions
Q:Can this laser rangefinder display the distance in meters, instead of yards?
A: Yes, it can! Just push the MODE button to change display from yards to meters.
Q:Does this laser rangefinder deliver good quality at low light conditions?
A: Since this laser rangefinder has a non-lighted display, the image quality at low light conditions is not so good. However, when at good lighting conditions, Nikon 8397 ACULON Laser Rangefinder delivers superb and impressive image quality.
Q:Does this laser rangefinder automatically turn off?
A: Yes, it does. It automatically turns off around 8-30 seconds.
With the best features , it is surely something to own and experience today! Where else can you find a laser rangefinder that is handy, made with quality, easy to use and delivers clear and accurate results at an incredible price?
Make your hunting, shooting, golfing or any outdoor activity fun and worthwhile by having this Nikon 8397 ACULON Laser Rangefinder.


Particle size analysis is the process of determining the size distribution of particles in a given solid, emulsion, suspension or aerosol sample. Different methods of analysis are employed to measure particle size, wherein some methods can be used for a wide range of samples while others are specific to particular samples. Particle size analysis forms an important part of several industrial processes for quality control, and determining the efficiency of the manufacturing process and product performance. Owing to this, it is extensively used in the manufacturing of aerosols, foods and beverages, paints and coatings, building materials and pharmaceuticals. According to the latest report by IMARC Group, titled “Particle Size Analysis Market: Global Industry Trends, Share, Size, Growth, Opportunity and Forecast 2018-2023”, the global particle size analysis market reached a value of US$ 200 Million in 2017.
One of the major factors driving the growth of the global particle size analysis market is the expanding applications of particle size analysis in the field of nanotechnology. This process is being used in the production of semiconductor components, constructed structures, cosmetic products, etc. Apart from this, growth in the pharmaceuticals industry has resulted in a heightened demand for particle size analysis where it is used in maintaining the quality of the various products. Moreover, technological advancements in the analysing processes along with augmented demand from the emerging regions are the other factors driving the market growth. Looking forward, the market is expected to grow at a CAGR of 5.4% during 2018-2023, reaching a value of US$ 274 Million by 2023.
The report has segmented the market on the basis of technology into laser deflection, Dynamic Light Scattering (DLS), image analysis and Nanoparticle Tracking Analysis (NTA). Currently, the laser deflection segment accounts for the majority of the total market share. On the basis of application, the report covers medicine and healthcare, mining and minerals, petrochemical, and food and beverages. Amongst these, the medicine and healthcare industry represents the leading application segment. On a regional-basis, North America dominates the market, followed by Europe, Asia-Pacific, Latin America, and Middle East and Africa. The report has also analysed the competitive landscape of the market with some of the key players being Malvern Instruments Ltd., Horiba Ltd., Beckman Coulter, Inc., Microtrac, Inc. and Micromeritic Instruments.
This report provides a deep insight into the global particle size analysis market covering all its essential aspects. This ranges from macro overview of the market to micro details of the industry performance, recent trends, key market drivers and challenges, SWOT analysis, Porter’s five forces analysis, value chain analysis, etc. This report is a must-read for entrepreneurs, investors, researchers, consultants, business strategists, and all those who have any kind of stake or are planning to foray into the particle size analysis industry in any manner.
Key questions answered in this report:
- How has the global particle size analysis market performed so far and how will it perform in the coming years?
- What are the key regions in the global particle size analysis market?
- What are the key application segments in the global particle size analysis market?
- Which are the major technologies in the global particle size analysis market?
- What are the various stages in the value chain of the global particle size analysis market?
- What are the key driving factors and challenges in the global particle size analysis market?
- What is the structure of the global particle size analysis market and who are the key players?
- What is the degree of competition in the global particle size analysis market?


Turner Designs Releases Turbidity Plus Sensor
Turner Designs has introduced a new turbidity sensor with a minimum detection limit of 0.05NTU and a maximum range of 500NTU. Those interested in harbor dredging, underground pipe installation and riverine applications in general will find value in these turbidity measurements at very low levels of detection. Keeping the instrument optical face clean is particularly important in these applications so Turbidity Plus includes an integrated wiper, which is triggered by the user. Turbidity Plus is designed for integration with multiparameter systems and dataloggers from which it receives power and the wiper trigger. It delivers a voltage output proportional to the turbidity of the sample, which can be correlated to nephelometric turbidity unit (NTU) values by calibrating with a standard of known concentration. Deployable to 200m (about 656 feet), Turbidity Plus is available with or without a plastic housing for simplified integration.


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Remote Monitoring of Wind Turbines
Defining the Problem:
A large utility company has a requirement to monitor multiple data points on a wind turbine. The turbine head is 300 feet above the ground. The data must be sent to a ground station, saved to a data logger, and displayed on a Honeywell chart recorder. The data will then be downloaded from a remote data collection site.
At the wind turbine head, several data collection points (both discrete and analog) must be acquired and sent to the ground station using Modbus TCP/IP protocol. The ground station is equipped with a Honeywell chart recorder that also serves as the Modbus master. The system will use Honeywell Ethernet radio links to send the information from the wind turbine head to the ground station, thereby eliminating the need for long Ethernet cable runs.
|Implementing the Solution:||Featured Products:|
The utility company has used Acromag products in their power plant monitoring and control systems in the past, so they are familiar with the equipment and trust in its accuracy and reliability.
Did this App Note help you today? Tell us what you think with these 4 quick questions.


|Número de publicación||US6900936 B2|
|Tipo de publicación||Concesión|
|Número de solicitud||US 10/854,943|
|Fecha de publicación||31 May 2005|
|Fecha de presentación||27 May 2004|
|Fecha de prioridad||31 Ene 2000|
|También publicado como||CN1183408C, CN1433528A, EP1257872A1, US6785049, US7057814, US20050002097, US20050185277, WO2001055783A1|
|Número de publicación||10854943, 854943, US 6900936 B2, US 6900936B2, US-B2-6900936, US6900936 B2, US6900936B2|
|Inventores||Gary T. Boyd, Richard A. Miller, Leland R. Whitney|
|Cesionario original||3M Innovative Properties Company|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citas de patentes (23), Citada por (8), Clasificaciones (25), Eventos legales (3)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
This is a divisional application of U.S. patent application Ser. No. 09/498,801, filed on Jan. 31, 2000, now U.S. Pat. No. 6,785,049, and incorporated herein by reference.
The invention relates to reflective displays, and more particularly to a compact illumination system for a reflective display.
Many optical devices, such as microdisplays in electronic cameras and other types of display system, require illumination by a beam of light having relatively uniform brightness. Generally, light sources, such as incandescent lights, arc lamps, and light emitting diodes, provide a nonuniform light output that is unsuitable for direct use, so the light is typically homogenized in a diffusing cavity before illuminating a display unit. The display unit is often a reflective display unit, for example a reflective liquid crystal display panel, an array of tunable mirrors or “electronic paper”. A polarization sensitive mirror is often used to direct light from the light source to the display unit.
The light source and display unit are typically mounted separately from each other on the display system housing, and are electrically connected via flex circuitry. This approach results in high component and fabrication costs, and a fault in the flex circuitry or in the connectors is often a primary failure mechanism for the display system.
Therefore, there is a need for a display system that is less expensive to fabricate and is more reliable than current display systems.
Generally, the present invention relates to an illumination system for a reflective display. The invention is believed to be particularly useful for microdisplays that use reflective displays. In the display system of the invention, the light source and display unit are mounted in a coplanar manner. This permits the light source and the display unit to be mounted on a single board, or even on a single substrate. Thus, the assembly costs may be reduced, and the reliability increased since the system is simpler, has fewer components, and omits the connectors and the flex circuit which tend to be unreliable.
One particular embodiment of the invention is an illuminated display device that includes a light source directing light generally along a first axis and a reflective image display unit disposed with an optical axis substantially parallel to the first axis. A reflective polarizing film is disposed to direct light from the first light source to the reflective image light display unit. The light source may include a reflector to direct light to the reflective polarizing film.
Another particular embodiment of the invention is an illuminated display device that includes light generating means for emitting diffuse, polarized light along a first direction and reflective display means for modulating reflected light with an image, the reflective display means having an optical axis substantially parallel to the first axis. Reflective polarizing means are disposed to direct the diffuse, polarized light from the light generating means to the reflective display means.
In another embodiment of the invention, an optical system includes a display device that has a first light source directing light generally along a first axis and a reflective image display unit disposed with an optical axis substantially parallel to the first axis. A reflective polarizing film is disposed to direct light from the first light source to the reflective image light display unit. A controller is coupled to the reflective image display unit to control the image formed by the reflective image display unit. Viewing optics transport the image formed by the reflective display unit to a user.
The above summary of the present invention is not intended to describe each illustrated embodiment or every implementation of the present invention. The figures and the detailed description which follow more particularly exemplify these embodiments.
The invention may be more completely understood in consideration of the following detailed description of various embodiments of the invention in connection with the accompanying drawings, in which:
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
The present invention is applicable to reflective displays and is believed to be particularly useful for microdisplays that employ reflective display devices. Amongst the advantages provided by the invention are a reduction in manufacturing costs for a display system and an increased reliability.
Reflective displays are used in several types of information display system.
The reflective image display unit 106 may also be a different type of unit, for example an array of individually movable miniature mirrors, such as the Digital Micromirror Device™ produced by Texas Instruments, or may be based on the use of so-called “electronic paper”, such as an electrophoretic display manufactured by E-Tek Inc., or a gyricon-based display manufactured by Xerox Corp. The invention is particularly advantageous for a reflective image display unit that modulates the incident light based on polarization rotation, such as an LCD, but may also be used for other types of reflective image display units.
Examples of where a reflective display may be used include microdisplays, for instance, in a viewfinder of an electronic camera. Electronic cameras include video cameras and digital cameras, and any other device that converts an optical image to electronic form. For example, a video camera 200, as illustrated in
Microdisplays may also be used elsewhere, for example in head-mounted displays such as DVD viewers, virtual reality goggles, wearable computer displays and internet appliances. A general approach to using a microdisplay is illustrated in
It will be appreciated that reflective displays are not restricted to use in microdisplays, but may also be used in larger displays, for example projection displays and heads-up displays.
One particular arrangement for a reflective display that may be used in a microdisplay is illustrated in FIG. 4. The reflective display 400 includes a three-color light emitting diode (LED) 402 for generating light. Light from the LED 402 is directed to a diffuser 404 that mixes and homogenizes the color of the light that is subsequently incident on the reflective image display unit 406. A pre-polarizer 408 polarizes the light that has passed through the diffuser so that light of only one polarization is incident on the reflective image display unit 406.
A brightness enhancer 410 may be placed before the diffuser 404 to enhance the brightness of the light reaching the reflective image display unit 406. For example, the brightness enhancer 410 may be a film having a prismatic structure on an input surface to direct off-axis light from the LED 402 towards the axis 412, such as BEF brightness enhancing film manufactured by 3M Company of Minnesota. Light reflected by the BEF brightness enhancing film may be recirculated by a diffusely reflecting cavity 413 containing the LED 402.
The brightness enhancer 410 may also be a reflective polarizing film whose transmission polarization state is substantially aligned with the transmission polarization state of the pre-polarizer 408. If a reflective polarizing film is used as the brightness enhancer 410, the LED 402 is advantageously enclosed within a diffusely reflecting cavity 413 so that the polarization of the light reflected by the brightness enhancer 410 may be randomized as it recirculates within the diffusely reflecting cavity. Randomization of the polarization results in a greater fraction of the light generated by the LED 402 being transmitted by the reflective brightness enhancer 410, thus increasing the optical efficiency of the reflective display 400. One example of a reflective polarizing film that may be used as brightness enhancer 410 is DBEF multilayer optical film manufactured by 3M Company of Minnesota.
Light transmitted by the pre-polarizer 408 is polarized in the block polarization state of a polarizing beamsplitter 412, that is the polarization state orthogonal to the transmission polarization state of the polarizing beamsplitter 412. Therefore, the light is reflected by the polarizing beamsplitter 412 towards the reflective image display unit 406. The reflective image display unit 406 spatially modulates the incident light 414 by polarization rotation. The reflected light 416 contains light in both the block and the pass polarizations for the polarizing beamsplitter 412. Only that light in the pass polarization of the polarizing beamsplitter 412, the image light 418, is transmitted to the eyepiece 420. A clean-up polarizer 422 may be placed between the polarizing beamsplitter 412 and the eyepiece 420 to enhance the contrast of the image viewed by the user. The use of the polarizing beamsplitter 412 for reflecting the illumination light from the LED 402 and for separating the image light 418 enables the reflective display 400 to be more compact.
The reflective image display unit 406, the polarizing beamsplitter 412 and the clean-up polarizer 422 are typically disposed within a housing 424.
There are, however, certain disadvantages with the arrangement for the reflective display 400. For example, the light source, including LED 402, the diffuser 404 and the pre-polarizer 408 is typically mounted on a light source board 426 while the reflective image display unit 406 is mounted on a display board 428, and the two boards 426 and 428 are separately attached to the housing 424. Typically the two boards 426 and 426 are electrically coupled using connectors and flex circuits. This can add significant manufacturing and assembly cost to the display system. Furthermore, the system complexity is increased and the flex circuits lower manufacturing yields and long term reliability.
The present invention is directed to a reflective display where the light source and the reflective image display unit are mounted in a coplanar manner. In other words, the light source is mounted so that its light is generally directed along a first axis that is parallel to the optical axis of the reflective image display device. An advantage of this approach is that the light source and the reflective image display unit may be mounted on a shared board, thus reducing assembly costs. This permits the light source and the reflective image display unit to be soldered to a printed circuit board using standard and relatively inexpensive printed circuit fabrication techniques. The light source and reflective image display unit may even be formed on the same substrate, for example by evaporation or sputtering, or other fabrication method, of the appropriate materials to form an organic or inorganic LED, thus further reducing assembly costs. Furthermore, the flex circuits are eliminated, which not only reduces manufacturing costs, but also eliminates low reliability components.
A schematic view of one embodiment of the present invention is illustrated in FIG. 5. The reflective display 500 includes a light source 502 that generally generates light parallel to the first axis 504. It will be appreciated that a light source such as an LED, tungsten bulb or the like, produces light into a large cone angle. However, the direction of maximum intensity, also known as the chief ray, is substantially parallel to the first axis 504.
The reflective image display unit 506 is disposed with its optical axis 508 substantially parallel to the first axis, in other words is mounted coplanar with the light source 502. Light 510 from the light source 502 reflects off at least one reflecting surface, and some light reflects off two reflecting surfaces, before being incident on the reflective image display unit 506. The reflecting surfaces may be provided by a polarizing beamsplitter 512, or a combination of a polarizing beamsplitter 512 and another reflector 514, as is explained more fully below. The reflector 514 may be considered to be part of the light source. A clean-up polarizer 516 may be disposed to enhance the polarization of the light transmitted through the polarizing beamsplitter 512 to increase contrast in the image seen by the viewer. The clean-up polarizer 516 removes, through reflection or absorption, stray light of the polarization normally reflected by the polarizing beamsplitter 512 that may have leaked through the polarizing beamsplitter 512.
Different embodiments of a light source are illustrated in
The second embodiment of light source 620, illustrated in
A brightness enhancer 626, for example a prismatic film or reflective polarizing film as described above, may be disposed to intercept light transmitted outwards from the cavity 624. Where the brightness enhancer 626 is a prismatic film, light falling outside a specific angular range is reflected back to the diffuser cavity 624, while light falling within a desired angular range is transmitted. Where the brightness enhancer 626 is a reflective polarizer, light in the block polarization state is reflected to the diffuser cavity 624, while light in the pass polarization state is transmitted. The light returned to the diffusing cavity is recirculated and its direction and/or polarization randomized, so that it may be transmitted through the brightness enhancer on a succeeding pass to the brightness enhancer 626.
A lens 628, such as a curved lens or a Fresnel lens, may be disposed to redirect the light transmitted by the brightness enhancer 626 so as to fall within a narrower cone angle.
The light transmitted out of the cavity 624 illuminates a diffuser 630. The combination of the diffuser 630 and the diffusing cavity 624 is used to make the light emitted from the light source 620 uniformly bright and have uniform color.
A third embodiment of light source 640, illustrated in
A fourth embodiment of a light source 660, illustrated in
Propagation of the light through the light guide 664 may result in mixing and homogenization of the light from the light emitter 662. The light 672 output from the light guide may be further homogenized by a diffuser 676. In addition, light diffusing particles may be embedded within a portion, or all, of the light guide 664 to further mix and homogenize the light.
The light 672 may be polarized by a pre-polarizer 678. The pre-polarizer 678 may be a linear polarizer, for example a dichroic absorber or a reflective polarizer, or may be a circular polarizer, for example a cholesteric polarizer or a dichroic absorber combined with a quarter-wave retarder film.
The lenslet array 674, diffuser 676 and pre-polarizer 678 may be positioned in a region of greatest extraction from the light guide 664 in order to facilitate mixing within the guide for homogenization or to place the outgoing light 672 at an appropriate height for illuminating the polarizing beamsplitter 512.
One of the advantages afforded by this embodiment 660 is its compactness in the direction parallel to the input surface of the reflective image display unit 506.
It will be appreciated that many different types of light source may be used, in addition to variations of the four embodiments illustrated in
The pre-polarizer may be a linear polarizer, for example a polymeric multiple layer reflective polarizing film, as described in U.S. Pat. No. 5,612,820, or a wire grid polarizer, for example as described in WO 94/11766, “A Reflective Polarizer”. The pre-polarizer may also be a circular polarizer, for example a cholesteric polarizer as described in U.S. Pat. No. 5,506,704. A cholesteric polarizer is particularly useful where the reflective image display unit is based on the modulation of circularly polarized light.
Likewise, a polarizing brightness enhancer may formed from a multiple layer reflective polarizing film, a wire grid polarizer or a cholesteric polarizer.
Any number of light emitters may be combined in a single light source using this technique, for increased brightness and for covering larger area displays. Furthermore, a reflective display may use more than one light source.
Where light from the light source 502 is reflected off two reflecting surfaces to reach the reflecting image display unit, a reflector 514 may be used for the first reflection and a polarizing beamsplitter 512 used for the second reflection. The reflector 514 may be part of the light source 502.
The reflector 514 may be made of a metal-coated substrate (plastic or metal), polished metal, a stamped metal sheet, thermoformed metal coated film, a thermoformed multi-layer optical film, or other suitable reflecting material. Furthermore, the reflector 514 may be flat, as illustrated in
The divergence of light in the x-z plane, emitted from the light source 702, is reduced upon reflection from the curved reflector 714. The light is directed to the polarizing beamsplitter 712 for transmission to the reflective image display device 706.
A reflector 734 that is curved in two directions is illustrated in FIG. 7B. In this case, the reflector 734 has a first radius of curvature lying in the x-z plane and a second radius of curvature lying in the y-z plane, where the y-direction is directed out of the plane of the figure, and is orthogonal to both the x and z directions. Light emitted from the light source 702 has it divergence reduced in both the x-z and y-z planes upon reflection from the reflector 734.
It will be appreciated that the reflector may also be singly curved with a radius of curvature in the y-z plane.
The polarizing beamsplitter 512 typically reflects light having one polarization and transmits light having the orthogonal polarization. The polarization may be linear or circular. One particular example of linear polarizer that may be used as the polarizing beamsplitter is a polymeric multiple layer polarizing film, such as DBEF manufactured by 3M Company, Minnesota. This is useful as a polarizing beamsplitter since it maintains a high degree of extinction over a wide spectral and angular range. Furthermore, this type of film may readily be deformed in one or two directions to form curved mirrors to more efficiently collect light from the light source, and to lower the overall profile of the illumination system. Another type of linear polarizer also suitable for use as the polarizing beamsplitter 512 is a wire grid polarizer.
The polarizing beamsplitter 512 may also be a circular polarizer, and may be a cholesteric polarizer. It will be appreciated that use of a cholesteric polarizer may also necessitate the introduction of a quarter wave retarder in order to convert light between linear and circular polarization. For example, where the reflective image display unit 506 operates on linearly polarized light and the light from the light source is also linearly polarized, then the cholesteric polarizer may be provided with a quarter wave retarder layer on its front surface so as to circularize the polarization of the light prior to incidence on the surface of the cholesteric polarizer. Furthermore, the quarter wave retarder linearizes the polarization of the reflected light before propagating to the reflective image display unit 506. Where the light from the light source is circularly polarized, the reflective image display unit 506 may be provided with a quarter wave retarder at its input so as to linearize the polarization of the light reflected from the cholesteric polarizer.
The polarizing beamsplitter 512 may be flat, or curved in one or two directions, as illustrated in
Advantages of the using polarizing beamsplitter that is flat or is curved in one dimension include the ability to directly laminate the clean-up polarizer 816 to the rear surface of the polarizing beamsplitter 822. Furthermore, simple mechanical devices may be used to provide the shape to the polarizing beamsplitter. For example, the polarizing beamsplitter 822 may be formed from a sheet of material that is constrained at its two opposite ends where the separation between the constraints is less than the overall length of the film so that the film buckles to take on a curved shape. In another example, the polarizing beamsplitter 822 may be formed from a sheet of material that is federal into a curved slot that conforms the sheet to the desired curvature. Both of these advantages reduce manufacturing costs.
A polarizing beamsplitter 832 that is curved in two directions is illustrated in FIG. 8C. This polarizing beamsplitter 832 has a first radius of curvature lying in the x-z plane, and a second radius of curvature lying in the y-z plane. A flat clean-up polarizer 816 may be positioned above the polarizing beamsplitter 832.
The doubly curved polarizing beamsplitter 832 may be shaped by vacu-forming. Furthermore, a laminate of polarizing beamsplitter and clean-up polarizer may be vacuu-formed so that the clean-up polarizer does not need to be mounted separately within the display.
One particular method of vacu-forming a doubly curved polarizing beamsplitter 832 is illustrated with respect to
A singly curved polarizing beamsplitter 822 generally shows higher polarization extinction over a wider angular range than the doubly curved polarizing beamsplitter 832 PBS, owing to the higher range of angles of incidence on the doubly curved surface. Thus, it becomes increasingly more important to use a clean-up polarizer 816 with a doubly-curved polarizing beamsplitter 832. A doubly curved beamsplitter assembly may be formed by first laminating the clean-up polarizer 816 to the polarizing beamsplitter 832 to form a lamination, and then vacu-forming the lamination using the vacu-forming technique illustrated in FIG. 10.
It will be appreciated that the polarizing beamsplitter may be singly curved with a radius of curvature in the y-z plane.
Different embodiments of polarizing beamsplitter are presented in the display devices shown in
The polarizing beamsplitter 932 may be flat, as illustrated, may be singly curved or may be doubly curved. A clean-up polarizer 936 may be disposed to clean-up the polarization of light transmitted through the polarizing beamsplitter 932 from the reflective image display unit 906. The clean-up polarizer 936 may be laminated or otherwise attached to the polarizing beamsplitter 932.
Different variations of the embodiment illustrated in
In the embodiment illustrated in
The invention is not limited to single light sources. Multiple light sources may be placed in coplanar positions relative to the reflective image display unit 906 to increase brightness or to improve illumination uniformity of the reflective image display unit 906. One particular embodiment using multiple light sources is illustrated in FIG. 9G. In this particular embodiment, the polarization beamsplitter 952 extends over the two light sources 902 as well as the reflective image display unit 906. Light from the light sources 902 is reflected to the reflective image display unit 906 which modulates and reflects the light back to the reflective polarizer 952. The modulated light is transmitted through the polarizing beamsplitter 952 to the viewer. A clean-up polarizer 956 may be disposed to clean-up the light transmitted through the polarizing beamsplitter.
Different reflector and beamsplitter designs have been explored for effectiveness in illuminating a reflective image display unit. The major characteristics of interest in designing a reflector/beamsplitter combination include the efficiency with which light from the light source is directed onto the surface of the reflective image display unit within the display unit's acceptance cone, and the uniformity of illumination across the reflective image display unit. An additional parameter that was studied was the maximum height of the reflector/beamsplitter combination above the display unit. this last parameter is important in designing display units that are used in confined spaces, for example in a camcorder or other type of camera. In the examples described below, the illumination of a display unit was calculated for a particular configuration of reflector and beamsplitter.
In the first example, illustrated in
The polarizing beamsplitter 1112 was assumed to be formed as a flat sheet positioned above the LCD display unit 1104 at an angle of 40° relative to the upper surface 1104 a of the display unit 1104.
The reflector 1114 was assumed to have a “tapered box” shape, being formed with an upper reflecting surface 1314 a, and side reflecting surfaces 1314 b (only one side reflecting surface shown in FIGS. 11A and 11B). The shape of the upper surface 1314 a was formed using an AUTOCAD spline function that connected the following points in the (x,z) plane: (5.5804, −0.2035), (5.9644, 0.9476), (5.6674, 1.6398), (5.1616, 2.2553), (4.1499, 3.2774), and (3.0478, 4.5078). The tangent at the first point was set by the point (5.7462, 0.1190) and the tangent to the last point was set by the point (3.5694, 3.9642). The cross-sectional shape formed by the “tapered box” was rectangular, and the aspect ratio of the rectangular cross-section was preserved throughout its length, from the light source 1102 to the output end.
The combination of flat beamsplitter 1112 and “tapered box” reflector 1114 produced the following results. The efficiency of illuminating the LCD display unit 1104 was 4.6%. The efficiency was defined as the ratio of light entering the LCD display unit 1104 within its acceptance cone angle over the total amount of light emitted by the light source 1102. The uniformity of illumination was measured by the ratio of the brightness of the maximum of illumination intensity on the LCD display unit 1104 over the brightness of the minimum illumination intensity on the LCD display unit 1104. In this particular case, the max/min ratio was 3.34. Lastly, the height, H, the maximum beamsplitter height above the LCD display unit 1104 required to enable this particular combination of reflector and beamsplitter to operate most effectively, was 5.57 units.
In the second example, illustrated in
For this particular combination, the illumination efficiency was 3.4%, the max/min ratio was 2.8 and the height, H, was 4.53 units. The overall illumination efficiency was less than in Example 1 because the flat reflector is not as good at gathering the light from the light source 1102 and presenting it to the beamsplitter for reflection to the LCD display unit 1104. On the other hand, the illumination uniformity is increased through the use of the curved beamsplitter. Also, use of the curved beamsplitter results in a reduction in the overall height, H.
In the third example, illustrated in
For this particular combination, the illumination efficiency was 4.6%, the max/min ratio was 1.93 and the height, H, was 4.53 units. The human eye is typically able to detect a max/min ration in excess of about 2, so this design approaches the region of acceptable uniformity where the eye does not detect any nonuniformity.
In the fourth example, illustrated in
For this particular combination, the illumination efficiency was 8.2%, the max/min ratio was 1.25 and the height, H, was 4.53 units.
In the fifth example, illustrated in
Summary of Illumination Characteristics for Different
H (arb. units)
While various examples were provided above, the present invention is not limited to the specifics of the illustrated embodiments. As noted above, the present invention is believed to be particularly applicable to illumination sources requiring a uniform, or substantially uniform, light output. Accordingly, the present invention should not be considered limited to the particular examples described above, but rather should be understood to cover all aspects of the invention as fairly set out in the attached claims. Various modifications, equivalent processes, as well as numerous structures to which the present invention may be applicable will be readily apparent to those of skill in the art to which the present invention is directed upon review of the present specification. The claims are intended to cover such modifications and devices.
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|Clasificación de EE.UU.||359/485.03, 362/560, 359/633, 362/558, 362/555, 362/583, 362/19, 359/631, 359/487.05, 359/489.11, 359/490.03, 359/487.02|
|Clasificación internacional||G02F1/1335, G02F1/13357, G02B27/02, G02F1/13, G02B27/28, G02B27/01|
|Clasificación cooperativa||Y10S362/80, G02B27/283, G02F1/133536, G02F1/13362|
|Clasificación europea||G02F1/1336P, G02F1/1335P5, G02B27/28B|
|1 Dic 2008||FPAY||Fee payment|
Year of fee payment: 4
|28 Sep 2012||FPAY||Fee payment|
Year of fee payment: 8
|17 Nov 2016||FPAY||Fee payment|
Year of fee payment: 12


I have analyzed the data from the dark fringe offset reduction to measure the contrast defect.
Figure 1 shows the signal of interest (B1 power, ITF optical gain, and RF DARM error signal)
Figure 2 shows looking at the relation between optical gain and B1 power and offset of 130uW seem to be present on B1 PD1.
Figure 3 shows the comparion between the RF DARM error signal and the B1 power, the relation here is also quadratic as the RF DARM error signal should be proportional to the DARM offset in meter (and the B1 power is quadratic with the DARM offset in meters). This yields an offset of 120uW.
After the unlock I could check that the PD itself has an offset of -7uW, so the numbers above correspond to actually 137uW and 127uW. Given that B1 PD1 sees only half of the power, the total contrast defect light is about 260uW. This is much higher than the ~120uW we had before increase of input power during the October commissioning break


Lack of real-time information on nutrient availability in cultivated soils inherently leads to excess
application of fertilizers in agriculture. As a result, nitrate, which is a soluble, stable and mobile component of fertilizers, leaches below the root zone through the unsaturated zone and eventually pollutes the groundwater and other related water resources. Rising nitrate concentration in aquifers is recognized as a worldwide environmental problem that contributes to water scarcity. Accordingly, developing technologies for continuous in-situ measurement of nitrate concentration in the soils are essential for optimizing fertilizer application and preventing water resource pollution by nitrate.
Here we present a conceptual approach for a monitoring system that enables in-situ and continuous measurement of nitrate concentration in soil. The monitoring system is based on absorbance spectroscopy techniques for direct determination of nitrate concentration in soil porewater without pretreatment, such as filtration, dilution, or reagent supplementation. A new analytical procedure was developed to improve measurement accuracy while eliminating the typical measurement interference caused by soil dissolved organic carbon. The analytical procedure was tested at four field sites over 2 years and proved to be an effective tool for
nitrate analysis in untreated soil. A soil nitrate-monitoring apparatus, combining specially designed optical flow cells with soil porewater-sampling units, enabled for the first time, real-time continuous measurement of nitrate concentration in the soil. The system provided outstanding and explicit data revealing the complexities of the temporal variations in soil nitrate concentrations in response to irrigation cycles and fertilizer-application pattern.
Such real-time measurements of soil nitrate levels are crucial for optimizing fertilizer application to increase agricultural yield while reducing the potential threat of groundwater contamination by down-leaching of nitrate from the soil.


Non-invasive positron emission tomography (PET) of vascular inflammation and atherosclerotic plaque by identifying increased uptake of 18F-fluordeoxyglucose (18F-FDG) is a powerful tool for monitoring disease activity, progression, and its response to therapy. 18F-FDG PET/computed tomography (PET/CT) of the aorta and carotid arteries has become widely used to assess changes in inflammation in clinical trials. However, the recent advent of hybrid PET/magnetic resonance (PET/MR) scanners has advantages for vascular imaging due to the reduction in radiation exposure and improved soft tissue contrast of MR compared to CT. Important for research and clinical use is an understanding of the scan-rescan repeatability of the PET measurement. While this has been studied for PET/CT, no data is currently available for vascular PET/MR imaging. In this study, we determined the scan-rescan measurement repeatability of 18F-FDG PET/MR in the aorta and carotid arteries was less than 5%, comparable to similar findings for 18F-FDG PET/CT.
- measurement repeatability
- vascular inflammation