Test Services

Akrometrix’ flatness characterization and analysis solutions provide sub 2-second data acquisition during dynamic temperature profiling. Profiles can be customized to match heating rates found in production ovens. Standard pricing includes 6 discreet measurement points along a profile of your choice.

Akrometrix encourages its clients and prospects to visit its Atlanta, Georgia testing facility to participate in the testing process and review the results in a customized data format consisting of 3D surface plots, 2D contour mapping, 2D diagonal plots, coplanarity tables, and displacement matrices to enable better understanding of the data. Our application engineers are always available for data interpretation.

Sample Flatness Testing Applications:

PCB/substrate characterization at temperature
Pb-Free processing implementation
Validation of Finite Element Modeling (FEM)
Supplier performance and conformity monitoring
Evaluation of different materials and constructions
Failure/defect analysis
Machined component flatness checks
Check out our Testing Applications Document for a more complete look at the kinds of samples that can be tested with our measurement techniques.

Services are available on a per part or project basis. Turnaround time ranges from 2 days to 10 days, depending on volume of testing required

Digital Fringe Projection

Flatness Measurement and Analysis Technique

The Digital Fringe Projection (DFP) technique compliments the shadow moiré technique by adding step height measurement capabilities at high data point density. This technique is particularly useful for measurement of connectors, sockets, assembled modules, and PCB local areas.

No grating is needed for the DFP technique, which helps with issues like outgassing and temperature uniformity sometimes seen with the shadow moiré technique. DFP also has the advantage of not being limited by data density, unlike the shadow moiré technique.

DFP has the disadvantage of warpage resolution being dependent on field of view. For this technique a field of view of 64x48mm, generating a measurement resolution of 5 microns, was chosen.

The strengths of the DFP measurement technique include:

Full field data acquired in less than 2 seconds
Able to measure sudden and large height changes up to nearly 20mm
High data point density

The DFP technique is offered as:

A DFP module on the AXP system
The base technology for the CXP system

Digital Image Correlation

In-plane strain and CTE measurement Technique

Digital Image Correlation (DIC) is a non-contact, full-field optical technique for measuring both in-plane and out-of-plane displacements of an object surface. A high contrast, random speckle pattern is applied to the surface of interest. Two cameras are mounted above the oven, viewing the sample from different angles.

Two simultaneous images from both cameras are digitized. Software identifies the same point on the surface from both perspectives, using pattern recognition of the speckles within a small pixel window. Using the principle of stereo triangulation, the spatial position of the pixel window relative to the cameras is determined in 3D space. Stepping the pixel window across the sample, the displacement of the surface can be mapped out in 3 axes.

The strengths of the DIC measurement technique include:

In-plane strain measurement at <150 microstrain
Calculate average surface CTE from strain and temperature data

The DIC technique is offered in the form of the DIC 2.0 module on the following Akrometrix tools:

AXP
PS200S

Shadow Moiré

Flatness Measurement and Analysis Technique

Shadow Moiré is a non-contact, full-field optical technique that uses geometric interference between a reference grating and its shadow on a sample to measure relative vertical displacement at each pixel position in the resulting image. It requires a Ronchi-ruled grating, a white line light source at approximately 45 degrees to the grating and a camera perpendicular to the grating. Its optical configuration is shown in the figure to the right. A technique, known as phase stepping, is applied to shadow moiré to increase measurement resolution and provide automatic ordering of the interference fringes. This technique is implemented by vertically translating the sample relative to the grating

The strengths of the shadow moiré measurement technique include: