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Creative Electron Acquires FocalSpot Legacy Product Service Business

by Glen Thomas in Creative Electron Comments: 0

VerifierSan Marcos, CA – Creative Electron, Inc., a leading American manufacturer of x-ray inspection systems announced today the acquisition of the legacy MXI service business (including services for FocalSpot, Nicolet, and Faxitron* system brands) from Nordson-MatriX-FocalSpot.

This acquisition makes Creative Electron the only authorized service provider for all legacy systems, thus consolidating the company’s leadership position as an x-ray technology and service provider. “Current owners of FocalSpot, Nicolet, and other legacy x-ray machines will now experience the Creative Electron customer support infrastructure,” said Dr. Bill Cardoso, President of Creative Electron. “Furthermore, our growing refurbished business will give customers the ability to maximize the value of their current x-ray machine towards the acquisition of a new TruView x-ray system.“

We will continue full service support to protect your investments in legacy systems, including: Nicolet, FocalSpot, Faxitron X-ray. We also offer an easy software update with TruView Image Processor

Creative Electron acquired the complete customer list, all technical documentation and drawings, and the existing supply of legacy service parts and refurbished machines. “We’re confident that Creative Electron’s dedicated and competent team will continue to provide the same excellent level of support to our customers as they have experienced so far,” said Mr. Frank Silva, Business Development Manager North-America with Nordson-MatriX.

For more information about this acquisition and to learn how you can request service for your x-ray machine, please contact Creative Electron at 760.752.1192, email us at info@creativeelectron.com, or contact us online at http://creativeelectron.com/contact-us/

 

info@creativeelectron.com | +1 760.752.1192

 

* Faxitron CS100 only. Faxitron is a registered trademark of Faxitron Bioptics, LLC

SMT Manufacturing Defects


old-manufacturing-line

In today’s post we cover the overall SMT manufacturing process and where defects come from. Enjoy!

For more educational videos please visit the X-Ray University.

Magnification and Field of View: X-Ray Inspection Explained


When talking about x-ray inspection, we have noticed over the years that magnification and field of view (FOV) are characteristics not well understood. To set the record straight, in this post we will describe in detail what each one of these parameters mean. The following figure shows a simplified diagram of an x-ray tube. Note that the modern tubes used in our systems are far more complex, but this diagram is very useful to illustrate magnification and FOV. The x-ray tube is the device inside the x-ray source that generates the x-rays that are used to project an image onto the x-ray sensor. The electron beam generated by the cathode is rapidly accelerated against the anode. Upon colliding with the anode, a beam of x-rays is generated.

x-ray-tube

Schematic representation of an x-ray tube

The random nature of the collision of the electron beam on the anode target creates an x-ray beam that is cone-shaped. As the x-ray beam moves farther from the anode target, the diameter of the beam increases proportionally. The angle of the x-ray cone beam, α, is determined by the angle of the anode target. The following figure shows the FOV at different distances from the source. This measurement is called source to object distance (SOD). It is important to note that the SOD is not measured from x-ray window to the object. Instead, the measurement starts from the target inside the tube to the object. X-ray source manufacturers give us that distance, so we can add it to the distance from the top of the source to the object.

field-of-view-magnification-x-ray-inspection

Change in field of view as a function of the source to object distance

What the previous image shows is that the diameter of the x-ray beam increases as it moves away from the source. For example, at 2” from the source, the diameter of the x-ray beam is 1.4”. To better illustrate this discussion, let us use the TruView Prime x-ray inspection system as an example. The minimum distance between the x-ray source and the x-ray camera in the TruView Prime is 6”. This measurement is called the SID – source to imager (x-ray camera) distance. The SID was designed to accommodate TruView Prime’s large 3”x4” high definition flat panel x-ray camera. That means that we would see vignetting of the image if we placed the camera closer to the source. The following image shows an example of vignette – an x-ray image when the camera is too close to the source. The dark corners in the image represent the regions where the x-ray beam is not shining.

x-ray-image-vignette

X-ray image with vignette

Now that we have a better idea of how to calculate the FOV based on the distance to the x-ray source and the angle of the x-ray beam, the next step is to connect it with the concept of magnification. We will use the TruView Prime as an example again. In the TruView Prime, the camera, or x-ray sensor, can move up and down to change the distance between the camera and the sample, as seen in the following figure.

x-ray-inspection-parameters

Field of view, magnification, source to object distance, object to imager distance: critical parameters in x-ray inspection

The magnification, M, of the system is given by:

x-ray-inspection-magnification-inspection-equation

In the example shown in the previous figure, the magnification of the system is 2:

x-ray-inspection-magnification-example-equation

That means that within the boundaries of the 3”x4” x-ray sensor in the TruView Prime, the sample image will be magnified by 2X. Thus a 100um2 feature in the sample will be projected in a 200um2 area of the x-ray sensor.

We hope this post was able to clarify some of the topics related to x-ray inspection. As usual, we’d love to hear your feedback!

 

Image Intensifier or Flat Panel Detector?


The question of what’s better – a digital Flat Panel Detector (FPD) or an analog Image Intensifier (II) – is a good one and depends on the actual usage of the system. There are multiple factors to consider when designing an x-ray inspection system. Image Intensifiers are old school technology from the late 1950’s and were the standard (only option other than film) up until some where around 2003- 2004. The technology is a vacuum tube (electron multiplier) with input and output windows that are phosphor coated to convert photons/electrons into visible light.

TruView-x-ray-inspection-Image-Intensifier

Image intensifier available for TruView X-Ray inspection systems. Photo by Hamamatsu Corporation

 

This same technology is used in a smaller scale for night vision. The main advantage of this technology when used in an x-ray inspection system is the ability to image down to 5 or 10kV. There were other advantages to II based systems over FPD; one is the speed. Image Intensifier based systems operate or produce images at 30 FPS (frame per second) – this is considered real-time. Two is gain, 15000 to 36000 gain makes the Image Intensifiers very efficient at converting electron/photons to visible light at low x-ray or light levels. This is key if you are imaging paper or very light density samples but no so important for most Non Destructive Testing or SMT/PCB applications. Third is the easy ability to create magnification that is not pixel based, the magnification can be achieved in the Image Intensifier by reducing the input window size electronically. A four-inch input on a 2/4 Image Intensifier can be reduced to 2 inches and double the inherent magnification above and beyond the physical geometrical magnification. This technique also has disadvantages because as you reduce the input size you also reduce the Photon statistics resulting in a need to increase kV or mA to offset the loss of incoming photons / electrons / light.

Now for the down side of Image Intensifier, the vacuum tube is convex at the input window, there is always an inherent pin cushioning effect on the resulting image and makes measurements difficult without doing some type of correction algorithms. All output windows of Image Intensifier’s are somewhere around 25mm regardless of the input window size, the input can be electronically manipulated but the output remains the somewhere around the same 25mm. By using lenses and cameras that are focused on the output window we can transfer the image to a monitor or computer. Again this is an area that allows us to increase magnification by using a variable lens system ( 7X zoom is typical) or choosing a lens camera combination to maximize magnification. The problems arise from the mechanical camera lensing combinations, the coupling of the camera to the lens and the combination of the two to the output window results in light loss and degradation of the image.

Flat Panel Detector standard in all TruView X-Ray inspection systems. Photo by Teledyne Technologies.

Flat Panel Detector standard in all TruView X-Ray inspection systems. Photo by Teledyne Technologies.

 

In the old days we used CCD cameras that needed to be run through an A/D converter before the computer processing, today we would use a mega pixel digital camera and avoid the A/D conversion. The camera/lens portion of this set up is very susceptible to dust and vibration and can easily become unfocused and require frequent cleaning and or adjustment. Then we get to the analog portion of the Image Intensifier. No matter what mega digital camera and lens combination you attach to the Image Intensifier it is always going to be 256 levels of grayscale. In other words, you get 256 shades of gray. This was fine for old school visual inspection but is really under utilizing the computing power of the newest image analysis software packages. Then there is the size factor for the standard electronics inspection Image Intensifier, the weight is somewhere around 20 pounds and the physical size is around 18 inches in length depending on the camera combination, the use of the Image Intensifier will require a larger cabinet/x-ray system regardless of the sample size. Then there is the issue of moving the Image Intensifier on a stage, tilting the weight becomes much more difficult and also exposes the camera/lens combination to vibrations which lead to an out of focus condition and reduced resolution. Image Intensifiers (outside of the night vision ones) operate at 24000 volts DC, so there is a chance of the vibrations to contribute to the failure of the HV power supply that is physically attached in some cases to the Image Intensifier.

Flat Panel Detectors became commercially available somewhere around 2000-2001 when computing power became available and more affordable. This availability was also enabled by considerable improvements to the semiconductor fabrication techniques needed to build large tiles of sensors. FPD uses a couple of methods to convert the scintillating layer of visible light to electrical signals that are then converted to a image that can be displayed and analyzed with the latest software/computer advances. The two most prevalent technologies are photodiodes and CMOS. There are a couple other technologies available but they are very cost prohibitive when building general electronics inspection systems.

The advantages of FPD are the size of the physical package, the flat input window and the grayscale or spacial latitude (4096 minimum grayscale vs. 256). The abundance of grayscale has resulted in computer analysis software algorithms that can detect a single grayscale variance thereby producing test results that are impossible to achieve through visual analysis (the human eye can not really detect grayscale past 256 shades). Furthermore, the resultant flat image requires no corrections for accurate image analysis and measurement. The signals produced are also digital, so there is no loss of the signal A/D conversion or image degradation because of lensing or camera configurations.

Larger FPD’s can also be economically produced by connecting multiple photodiodes or CMOS panels together as opposed to large area detectors made from single sheets of amorphous silicon. There are no moving parts (focus – zoom – iris) on a FPD and the requirements to move (z-axis / tilt) are fairly simple as well as no dust or vibration concerns. FPD detectors had only two disadvantages or concerns when compared to Image Intensifiers. One is the speed; typically FPD’s will capture images at speeds of less than 30 FPS although the speeds are increasing as the cost for the increased speed is decreasing. Modern FPDs used in Creative Electron TruView X-Ray Inspection systems come standard with 30 FPS speeds. The second disadvantage is the FPD’s need for high flux or high photon statics. Typically a FPD will require a higher kV \ mA combination (wattage) to achieve a usable x-ray image vs. an image intensified system. However recent advances in FPD technology has greatly bridged this gap.

The original FPD’s were very expensive and painfully slow when compared to Image Intensifier/ camera systems but the trend has been that of larger FOV / Panel sizes running at faster speeds (30 FPS) while at the same time bring the costs in line with Image Intensified systems. The use of FPD’s is pretty much the standard in industrial cabinet x-ray systems today.

There were only a few reasons that an Image Intensifier based systems would excel over a FPD based system, that being a low density sample requiring very low penetration (paper) or speed/FPS and the speed issue is quickly becoming a non-issue. Please let us know what you think about this post by including your feedback in our comments area.

What is X-Ray Inspection Resolution?


Here are a few things to think about before you ask that question.

During my years in the x-ray world I have been asked that question thousands of times and I provide the industry standard answer of some number in microns or how many line pairs per mm.  Both methods are totally valid and industry acceptable measurements of x-ray system resolution.

The problem I have always had with this answer is this, both are measurement results that are exacted under the most controlled circumstances imaginable.  An individual that has an in-depth understanding of x-ray imaging techniques performs these measurements: penetration, power and magnification are optimized to perfection.  This individual in most cases is also an expert on the imaging software suite in question.  On top of that the gauges used for taking these measurements are made of very low-density materials and have their own inherent limitations, which limit the use of higher kV and mA settings.

The major reason both of these measurements are not the end all is both are dependent upon magnification, you will always see the “at maximum magnification” behind the Line Pair Per mm (lp/mm) and overall system measurement results. The reason for this is without the magnification it would be impossible to see the extremely small details of the test gauge on the system monitor.

The second reason these two measurements can be deceiving is power or really the lack of power needed to image these two extremely low-density gauges. X-ray tubes with small spot sizes perform best at low power, a 5 micron x-ray tube will provide the best images at 4 or five watts of total power, increase the total wattage to image denser samples and the iso watt control of the x-ray tube will open up the spot size to dissipate the heat on the anode as total power to the x-ray tube is increased. When the spot size is enlarged your resolution has just been decreased from that starting number of say 60 lp/mm to say 20 lp/mm.

If your typical sample has a density above the density of the lp/mm gauge or requires a larger field of view with magnification less than system maximum you can’t assume that you are going to get the maximum resolution results during daily use on your production floor.

Line pair gauge used to measured the resolution of x-ray inspection systems

Line pair gauge used to measured the resolution of x-ray inspection systems

I am sure you are getting the idea here … these numbers are not real world numbers and should only be used as a starting point.

So… you’re thinking “ how do I chose an x-ray vendor or x-ray system manufacturer if I don’t use the industry standard measurements as the deciding factor?

The answer is simple; send your typical samples to the x-ray system manufacturer to get a demo. By using your real life samples the x-ray system will be adjusted out of the maximum resolution range into a more realistic operating range for the power required and magnification to image your samples. By using your typical samples you will get to see what the true resolution of the x-ray system will be on your production floor, which is really the only number you care about anyway.

For more information please don’t hesitate to contact us. We’d be happy to prepare a complete report with the x-ray inspection images of your samples.