UDI Labeling: The Relationship between Depth and Laser Power

The depth of laser markings on medical instruments is directly related to the laser power. Material properties, the processing environment and equipment condition must be taken into account.Metals like stainless steel require a higher power level to achieve a stable depth, while plastics require a controlled power level to avoid melting.In actual practice, it is recommended that a gradient test be used to determine the parameter combination, and that the equipment be regularly maintained to ensure output accuracy, so as to meet the requirement of the UDI mark for permanent readability.

Why is the depth of the UDI so important?

The laser marking of unique device identifiers (UDIs) on medical devices must meet strict requirements for readability and permanence.If the mark is too shallow, the product may not be traceable after it has been worn down. If it is too deep, it can damage the product, especially precision instruments.In practice, the depth of the mark depends on the hardness of the material, its surface treatment, and the conditions under which it will be used. For example, the depth of marks on stainless steel and titanium is usually 0.05-0.1 mm greater than that of marks on plastics.

How does laser power affect engraving depth?

Laser power is a key factor in determining the depth of a mark.The greater the power, the higher the instantaneous energy, and the more obvious the degree of material vaporization. But it is not always true that the higher the power, the better.

The type of material determines the power range.

For example, aluminum alloys can be used for low- to medium-power lasers of 30-50W, which ensure clarity and avoid burning the edges. On the other hand, ceramic materials require high-power lasers of over 80W to create a stable depth.

The relationship between power and speed.

High power and fast scanning reduce the affected area, and are suitable for thin-walled parts. Low power and slow scanning are suitable for deep engraving on rough surfaces, but it is necessary to pay attention to avoiding material carbonization.

The question then was, how to find the right laser parameters?

First we did some small-scale tests.

After obtaining basic data such as density and melting point from the materials supplier, he suggests that the power gradient be raised by 10 % at a time in non-critical areas, observing the effects on depth and edges.

Environmental factors must also be taken into consideration.

When humidity is high, it is necessary to reduce the power to prevent the lens from fogging up. When there are large temperature fluctuations in the workshop, it is recommended that the machine be calibrated after it is turned on each day.

Don't overlook the impact of maintenance.

The actual output power of older lasers can drop by 20-30 %, so regular power meter checks and replacement of seriously degraded mirrors are necessary to ensure consistency in the depth of the marks.