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Why coin portrait is the side face? And banknotes is the face?

Money is the most indispensable thing in everyday life.We use it every day, but have you ever noticed those notes and coins?Did you find that the portrait-bearing coins are almost flanked, but the portrait on the banknote is generally positive, and so is the currency of most countries. Is there any scientific basis for this?

In fact, the portrait of a metal coin is entirely carved texture resulting in different shades to display portraits. However, it is hard to carve out a front view that is fine enough to be clearly identifiable if it is to be as small as a coin.

Although the front portrait is sophisticated, but it can use this point to identify counterfeit money. This is one of the reasons why many large denominations are generally paper-based.

Today,let's learn some knowledge about LASER ETCHING in prototyping,little different with carved texture.

Laser etching is also called laser engraving or laser marking. It is a kind of optical surface treatment process, which is similar to screen printing(prototype surface finishing of screen printing). But the process is different, the price is different.

Laser etching principle:

1. The use of high-intensity laser focused laser beam emitted at the focus, so that the material oxidation and processing;

2. Marking effect is through the evaporation of the surface material to reveal the deep material, or through the light can cause surface chemical and physical changes in the trace or burn some of the material by light energy, and "engraved" traces. Or burn some of the material through the light, showing the desired etching graphics, text.


1. Engraving speed refers to the speed at which the laser head moves, usually expressed in IPS (inch / second); high speed leads to high productivity; speed can also be used to control the depth of cut or engraving; for a specific laser intensity, The slower the speed, the greater the depth of cut or engraving. Engraving speed can be adjusted by the laser engraving machine control panel, you can also use the computer's print driver to adjust. In the range of 1% to 100%, the adjustment is 1%.

2. The greater the engraving strength, the deeper the depth of cutting or carving.

3. The spot size can be adjusted with lenses of different focal lengths; the small spot lens is suitable for high resolution engraving; the large spot lens is suitable for lower resolution engraving but it is the best choice for vector engraving; Standard configuration is 2.0 inches lens, the spot size in the middle, suitable for a variety of occasions.

Material Available:


Etching file required:AI,CDR,PDF,etc.

The performance of a laser engraving machine, mainly by its engraving speed, engraving intensity and spot size to decide.

Contact SG Prototype Team,easy and fast prototyping.

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