Skip to content

What is PCB SMT X ray Checking

When you see the term “X ray checking”, what comes to your mind? It is unbelievable for some designers that this term has to do with the Printed Circuit Board. If you are new to PCB designs, it is paramount you find out more about “What is X ray Checking?”

Interestingly, X ray is important in the world of PCB. This is primarily because it can penetrate every layer of your PCB so as aid inspection of the inner layers. Also, x ray checking helps with assembly of hard soldering of complex boards. In this article, you shall know everything you related to what x ray checking is about.

What is X ray Checking?

When it comes to soldering the PCB, you can’t ignore the important aspect of x ray checking. It really helps to inspect each layer of the PCB. This inspection needs to be carefully done.

Meanwhile, it is no doubt that across the globe, the circuit board inspection using the x ray is fast becoming more acceptable among engineers, designers, and PCB experts. However, this x ray technology is becoming faster and better every day.

Plus, X ray checking has to do with how well the layers of your circuit board can connect firmly. Hence, this x ray technology is an automated x ray system for inspection. Accordingly, this x ray checking helps to find out every unseen feature in your PCB.

However, do not forget in a hurry that x ray checking is not just limited to the world of technology. Also, in aerospace engineering, electronic manufacturing, and medicine we use this term. However, it may then have various meanings. For instance in medicine, the medics can carry out x ray to check some fractured bones in the body. Similarly, in the world of PCB, x ray checking helps to detect faults or errors during the manufacturing process of the PCB. Moreover, the x ray checking helps to test the quality of your circuit board. With this x ray technology, there are ways to avoid any damage on your PCB.

What Factors Affect X ray Checking?

There are some underlying factors that affect how you inspect the layers of the PCB. These are listed below.


The Surface Mount Technology can affect the x ray checking of your device. The SMT affects how packages as well as leads become smaller. This way, it makes the circuit board have some density that is higher. As such, the PCB has some unseen components in its layers.

However with the higher density, the size decreases making the components of the circuit board become almost impossible for checking. The x ray checking then helps out to figure out each component of your PCB.

Component Size and Placement

The placement of each component of the circuit board influences the x ray checking. This implies that, when one is checking the component through the x ray technology, the size of each component determines how you inspect it. To save space, the devices are decreasing day by day making them more layered.

What are The Features of the X ray checking Devices?

For inspection of the layers of the PCB, there are ways the x ray checking works. However, the x ray checking devices have three simple features. Hence, they are listed below.


This has the ability to change the position of the samples in varying bearings or directions. This feature enables you to check your PCB from different angles. Also, this affects the magnitude from which you do the x ray checking of the circuit board.

X ray Tube

For anyone to have the ability to set up the x ray photons, you simply need the x ray tube. Plus, this is one of the features of the x ray checking devices.


This is an important feature of this device. It has the capacity to transform the photons into images. All it does is to sample various catches. Thereafter, it receives the x ray photons. Yet, it converts these into the required images. The heavier components consume more x ray photons. Wherefore, the lighter components are more translucent.

What are The Benefits of Using The X ray Checking Device?

There are benefits for inspection of the PCB using the x ray technology. Note that the metal is mostly dim for the images of the circuit board using the x ray technology. However, you see transparency when it is glass or ceramics. Then, it becomes so easy to view every metallic element.

This allows you to view different qualities of your circuit board. Also, you can know more about the varying problems that may arise. These include the following.

Solder Voids

These occur during soldering. However, what causes it is as a result of the entrapping of gas which is mostly due to the water infection of the solder paste. Plus, the solder voids reduce the conductivity of heat at any solder joints. However, this can lead to any defect physically. Also, it decreases the possibility of readability. For you to identify this defect, you use the x ray checking device. So, you need to use it regularly.

Solder Bridges

These are problems you find common to PCB. However, the X ray Checking helps to easily find out about it. This defect occurs as a result of the closeness of your solder joints. However, this problem may not be easily known because other elements hide it. You cannot view it through optical checking. Only x ray checking helps you view it.


We believe now that everyone can understand that the x ray checking is important in the manufacturing of electrical devices. What is X ray Checking? It is simply the inspection of the layers of the components of your PCB. X ray checking helps to easily detect any defects which mere optical inspection can’t find out. Therefore, it is crucial you use this regularly during your assembly of the circuit board. It helps you easily detect the issues that may arise in future.