Laser black marking for UDI

Laser marking of medical devices has many advantages, such as product traceability, product liability, quality control, distribution regulation, and counterfeit prevention. The markings must have uncompromising durability throughout the lifetime of the device to ensure patient safety.

Laser marking has rapidly become the preferred UDI marking process.

The FDA requires that all medical devices are marked with a Unique Device Identifier (UDI).

The marking must have lifelong durability to ensure traceability and patient safety.

It must contain plain text which is readable by humans as well as machine-readable code. Both must be permanently legible because traceability is crucial for medical implants and surgical devices. An ultrafast laser provides a smooth mark with high contrast.

Marking of all kinds of material

Medical devices can range from implants and catheters to less invasive multi-use surgical tools such as scissors, forceps, and scalpels.

Typical materials that are used in the manufacture of medical devices are:

  • Stainless steel
  • Aluminum
  • Titanium
  • Plastics (such as PEEK, HDPE, nylon)

All can be marked using our ultrafast lasers.

Cost-effective permanent marking

Most marks are required to remain durable after regular use and cleaning, which makes laser marking ideal.

Laser marking is an attractive and cost-effective marking solution with many advantages: The process reliability, the non-contact nature, the inherent flexibility, the capability to create intricate details, the micron precision. And there is no need for consumables.

Why use ultrafast lasers?

Ultrafast lasers have many advantages compared to nanosecond lasers. You can mark a wide range of materials due to the short pulse duration that gives a high peak power. The short pulse duration reduces the unwanted thermal effects of traditional laser marking.

Medical device markings must repeatedly withstand the high temperatures and humidity of autoclave cleaning and sterilization. Conventional thermal laser markings typically fade or corrode when cleaned frequently.

Our ultrafast product range produces high-contrast black marking on stainless steel. The marking is insensitive to the viewing angle. These markings are smooth to the touch and do not encourage biological traps.

Ultrafast lasers create smooth marks which can survive many cleaning cycles. During ultrafast laser marking, the laser removes no material, and there is no microcracking or surface damage.

The ultrashort pulses produce nanostructures on the surface of the medical device. These structures trap light and provide a high-contrast matt black “printed” appearance. You can see the marking from every angle.

The markings are smooth to the touch and do not cause biological traps.

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Summary

The ultrashort pulses delivered by NKT Photonics’ ultrafast laser range are well suited to marking in the medical industry and fulfilling the requirements for UDI-compliant marking.

The ORIGAMI XP is the first all-in-one, single-box, microjoule femtosecond laser on the market. The laser head, controller, and air-cooling system are all integrated into one small and robust package, with a footprint so small it even fits into a hand-luggage!

Contact us now for more information

The development of femtosecond lasers has transformed the micromachining technology. It enables machining of thin, transparent and semi-transparent materials with high precision and quality at high speed.

Femtosecond lasers offer a reliable method for producing cuts, holes, and scribes in brittle materials.

Ultra-short pulses and very high peak powers

Thin glass is widely used in photonics, microelectronics, displays, and biomedical chip manufacturing and has created a need for a reliable high-yield high-quality glass machining process.

Earlier, laser processing of glass was a very low-yield process due to the long pulses that caused thermal damage. Today, femtosecond lasers provide ultra-short pulses with very high peak powers that allow for
surface and internal bulk material modification of thin transparent materials.

An ultra-short pulse delivers energy at a time scale shorter than the electron-phonon coupling processes in any material.

Figure 1. Sample of 100 µm thick AF 32® eco glass that has been cut with ORIGAMI XP laser.

The ultra-short pulse width suppresses the formation of the heat affected zone and thermal damage. This results in high-precision and high-resolution processing through a cold ablation regime – with unrivalled process reliability.

A tightly focused beam enables very high-resolution micro-machining of complex shapes at micro-scales.

Glass cutting

In our application lab, we have demonstrated cutting of 50 and 100 µm thin AF 32® glass by ablation, using our infrared ORIGAMI XP laser. Figure 1 shows cuts with very clean-cut edges. There is no thermal damage or cracks as typically seen with long-pulse lasers.

In contrast to machining achieved by internal modification of glass, known as “stealth” laser machining, the ablation process is overall faster and provides more flexibility for cutting various closed shapes, such as circles.

Figures 2 and 3. Complex lines and curves cut in 100 µm thick AF 32® eco glass with ORIGAMI XP laser. The cut profile is clean and free of microcracks.

Glass Scribing

The high growth in the manufacturing of thin, flexible displays for mobile devices has driven investment into new thin glass cutting and dicing techniques. In one such technique, known as scribe and break, glass is scribed using lasers.

Glass scribed using ultrafast lasers provides a more consistent and predictable breaking process with straighter-cut edges and higher yield.

In our application lab, we have shown clean scribes of 20 µm depth in a 50 µm thin glass, as shown below. The cross-section profile shows an ideal clean V shape without any cracks that is optimal for the subsequent breaking process.

Figures 4 and 5. Scribing of 50 µm AF 32® eco glass with ORIGAMI XP laser. The profile of the scribe shows a V-shape channel with a 15 µm width and a 20 µm depth.

Glass drilling

Figure 6. Four <15 µm-diameter holes in 100 µm thick AF 32® eco glass drilled using ORIGAMI XP laser.

Lasers provide a non-contact and clean hole drilling technology that allows drilling of small holes by percussion as well as trepanning technique.

In our application lab, we have drilled very small 15 µm diameter holes in 100 µm thick glass, using our infrared ORIGAMI XP laser. Drilling of even smaller holes is possible using our green ORIGAMI XP laser.

Summary

Our results demonstrate that femtosecond pulses, delivered by NKT Photonics’ ultrafast lasers, are well suited for micromachining of thin glass.

The ORIGAMI XP is the first all-in-one, single-box, microjoule femtosecond laser on the market. The laser head, controller and air-cooling system are all integrated in one small and robust package, with a footprint so small it even fits into a hand-luggage!

The ORIGAMI system is based on a compact monolithic chirped pulse amplification platform capable of delivering up to 70 μJ pulse energy at 1030 nm, a 5 W average power, and a pulse duration below 400 fs.

Download the application note here.

Get in touch to know more
NKT white glass
Lab-on-a-chip sample produced by NKT Photonics’ ORIGAMI XP femtosecond laser.

For biomedical applications, laser micromachining of glass is in high demand – particularly to create lab-on-a-chip or microfluidic chips.

One of the biggest challenges when making lab-on-a-chip is to machine the high-precision pipes, vessels, and valves inside the glass chip.

Micromachining of very small features in glass is difficult due to its brittleness and transparency. With conventional tools, it is practically impossible. However, ultrafast lasers can do the job. When the pulse duration is below some tens of picoseconds, the laser-material interaction enters the cold ablation regime and the machining quality and precision become very high.

Lab-on-a-chip enables faster diagnoses

The lab-on-a-chip technology is expected to become an important diagnostic tool. These miniaturized devices allow healthcare providers to perform a range of diagnostic tests with very small quantities of reagents and test specimens. Due to their portability, tests can be performed in the field, away from laboratory environments.

High-power ultrafast laser pulses cut through glass

Conventional micro-manufacturing fabrication methods, such as lithography, imprinting, and soft lithography, have been used for the preparation of microfluidic chips. However, these methods face challenges to achieve complex microfluidic chips with multifunction integration as they require many steps and are costly.

Tightly focused femtosecond laser pulses can produce general microfluidic chips with multifunctional features, cost-effectively.

The ultra-short pulse width provides the incredible peak power needed for surface and internal bulk material modification for scribing – even in transparent materials.

Close up of channel produced with a femtosecond laser.

Ultrafast lasers ensure high precision and quality

By utilizing the laser’s highly spatial selectivity, it is possible to precisely set the interaction region at a specifically localized area of the material. This enables a very high-resolution patterning and sculpturing of complex three-dimensional shapes at micro-scales in transparent materials.

The energy delivered by an ultrashort pulse is at a time scale shorter than electron-phonon coupling processes. The ultrashort pulse width suppresses the formation of the heat-affected zone, allowing laser processing with high precision and resolution through a cold ablation regime with unrivalled process reliability.

Close up of a channel measuring <10 µm in depth. Very fine depth control and channel width can be achieved with our ultrafast lasers.
Close up of lab-on-a-chip sample processed with our ORIGAMI XP femtosecond laser, showing a circular reservoir feature with diameter of ≈0.6 mm.

Summary

The ultrashort pulses delivered by NKT Photonics’ ultrafast laser range is well-suited for producing lab-on-a-chip devices.

We recommend our ORIGAMI XP for laser processing of glass and other transparent materials.

The Origami XP is the first all-in-one, single-box, microjoule femtosecond laser on the market. The laser head, controller and air-cooling system are all integrated in one small and robust package, with a footprint so small it even fits into a hand-luggage!

The ORIGAMI system is based on a compact monolithic chirped pulse amplification platform capable of delivering up to 70 μJ pulse energy at 1030 nm, a 5 W average power, and a pulse duration below 400 fs.

Download this application note as pdf.

Contact us now for more information

PMMA has excellent optical properties and is suited for many applications. PMMA is also known as acrylic or acrylic glass. It is a transparent, ultraviolet (UV) light, and scratch-resistant, lightweight, rigid thermoplastic material with an excellent optical transmission.

PMMA is a tough plastic that exhibits glass-like qualities at half the weight and with up to 10 times the impact resistance. It is a great alternative to the high cost glass and is widely used as a shatterproof replacement for glass.

Due to PMMA’s excellent optical clarity, high light transmission, and scratch resistance, it is widely used in the manufacturing of LCD/LED tv screens, laptops, smartphones display as well as electronic equipment displays. PMMA is also used as cover materials in solar panels because of the excellent UV resistance and light transmission, which allows high energy conversion efficiencies. Furthermore, the material is high purity and easy-to-clean and can be used to fabricate incubators, drug testing devices, and storage cabinets in hospitals and research labs.

Ultrafast pulses give a high precision

The growing use of PMMA in medical device and display manufacturing demands a high-precision micro-machining process to create fine features.

Ultrafast lasers have delivered high-quality solutions to similar challenges in the automotive, aerospace, and semiconductor industries. These lasers provide a precise, non-contact micromachining processing technique with a minimal need for post-processing.

Traditionally, longer-wavelength infrared (IR) CO2 lasers have been used to process PMMA. It works well when machining large features. However, thin PMMA films used in display and medical device manufacturing requires precise machining of much smaller features (10-100s of a µm).

High peak-powers remove material instantly

Femtosecond lasers provide a cold ablation micromachining process due to their high peak-power. The high peak-power breaks down the material almost instantly and removes it without affecting the surrounding material. It is an ideal solution to process fine 100s of microns, or smaller, features with a minimal heat-affected zone (HAZ).

An optimized PMMA machining process, using CO2 lasers, has shown a heat-affected zone (HAZ) of up to ≈100 to 400 µm1. A different laser source is required to create 100s of microns, or smaller, features. A high peak-power femtosecond laser can be one of the solutions.

In our application lab, we have processed a thin 100-micron PMMA film using our compact ORIGAMI XP femtosecond laser. Figure 1 below shows a 25-micron diameter percussion-drilled array of holes and a large trepanned 500-micron diameter single hole using infrared wavelength.

Figure 1. Holes drilled in 100 µm thick PMMA film using an infrared ORIGAMI XP laser.
Figure 2. Magnification x500.0.

The inspection of a large 500-micron diameter hole showed that edge roughness is ≈2.5 µm and HAZ is ≈10 µm. The edge of the 500-micron diameter hole also showed many flakes.

Figure 3 and 4. Quality of holes
drilled using an infrared ORIGAMI XP laser

Further improvement in hole quality was achieved by using a green wavelength. Holes drilled using the green ORIGAMI XP are shown below. The use of a green wavelength laser clearly shows improvement in the edge quality as well as a reduction in HAZ. We observed very clean edges with HAZ reduced to ≈4.5 µm.

Figure 5 and 6. Hole drilled in 100 µm thick PMMA film using a green ORIGAMI XP laser.

Conclusion

Our results show that our ORIGAMI XP femtosecond laser is well suited to machine PMMA films. We have seen that using infrared wavelengths to process PMMA films yields much better quality than a long-pulse laser CO2 laser. A green wavelength laser can improve quality even further.

Summary

Our results demonstrate that femtosecond pulses, delivered by NKT Photonics’ ultrafast lasers, are well suited for micromachining of thin glass.

The ORIGAMI XP is the first all-in-one, single-box, microjoule femtosecond laser on the market. The laser head, controller and air-cooling system are all integrated in one small and robust package, with a footprint so small it even fits into a hand-luggage!


The ORIGAMI system is based on a compact monolithic chirped pulse amplification platform capable of delivering up to 70 μJ pulse energy at 1030 nm, a 5 W average power, and a pulse duration below 400 fs.

Download this application note here.

Get in touch
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