Higher resolution cameras combined with high speeds allow for move to 3D required by manufacturers of PCB inspection equipment.
The trend towards miniaturization and higher density is of course carried into PCB manufacturing as well, presenting new challenges for inspection equipment manufactures to maintain or improve accuracy and throughput.
With printed circuit board (PCB) Manufacturing, there are several verification steps required, including automated optical inspection of the PCBs and components and Solder Paste Inspection (SPI).
Automated Optical Inspection of PCBs and Components
To increase performance while reducing size results in smaller chips, different packages, higher density printed circuit board, and multi-layered, more complex boards. There is also large variety of sizes of the components.
3D AOI offers significant improvements over 2D, such as full dimensional measurements to verify the exact component information.
Larger resolution cameras, such as 25 Megapixel, can be of benefit when dealing with a huge variety in components with a very flexible field of view. With Camera Link deca or even faster CoaXPress, high frame rates can still be achieved at this resolution (32 fps+).
For 3D inspection several methods can be used, but all require at least 3 sequential images are used to reconstruct via a specific algorithm the 3D information. Since throughput cannot be compromised, cameras that enable at least 3 times the frame rate, higher sensitivity, and highly reproducible images are required. For more information on camera requirements for 3D, click here.
Solder Paste Inspection
With solder paste inspection, 3D inspection and measurement is also becoming more important with changes in the amount of solder paste used. As the solder bumps and balls become smaller, the volume of the solder paste is the important measurement rather than just the width. As the solder provides the connection between the printed circuit board, it is critical to measure the solder volume to verify solder joint reliability. This is done both pre reflow and post reflow of the solder.
As mentioned above there are demanding camera requirements for 3D measurements.
High-resolution cameras combined with high speeds that make full use of select image sensors provide the images required for 3D inspection and metrology to ensure the quality of components that go inside your latest smartphones and tablets.
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