The accuracy of a coin is completely dependent on how well the reliefs or molds are created.
If this isn’t done just right, you risk:
- Poor quality coins
- Coins that are not all identical
- Enabling counterfeiting
Clearly official mints are under a lot of pressure to create measured and traceable mints.
Measuring Coins and Minting Reliefs
Here’s how to they turn a coin relief into digital data.
- A 10x scaled version of the coin is created in plaster mold
- The relief (and coin made from it) is measured by a laser distance sensor, such as Optimet’s ConoPoint-10 sensor
Okay, that doesn’t sound so hard, does it?
Unfortunately, this isn’t quite so simple. There are a number of things that make plaster reliefs particularly difficult to measure:
- Plaster is translucent which causes the laser to partially penetrate the relief, causing beam spreading. This leads to a much higher level of noise than usual.
- Plaster is delicate and can’t be measured with touch sensors.
- Due to the nature of the application, very high precision (2-3 μm) is necessary.
- Depending on the coin design, there are often parts which have sharp angles that cannot be measured with standard triangulation sensors.
But I won’t leave you hanging. There’s a way to solve all these problems in one go.
It’s called ConoPoint-10.
Here’s how each of the above can be addressed by just using the Optimet ConoPoint-10 sensor:
- Unique polarization scanning technique was created in order toimprove the signal to noise ratio when scanning translucent materials.
- Optimet’s sensors use laser technology and don’t come into any contact with the object being measured.
- Depending on the lens uses, ConoPoint-10 has sub-micron level precision.
- Optimet’s unique collinear technology allows measurement of sharp angles and deep holes without a problem.
Contact us for more information on your particular application challenge.