What are the noteworthy trends and innovations in laser marking in 2023?

The early introduction of CO2 lasers for marking occurred in 1967, and the technology reached maturity in the mid-1970s through commercial modern CO2 laser systems. Since then, laser marking systems have become the main force applied in a wide range of industries, including aerospace, medical equipment manufacturing, pharmaceuticals, and retail.

Trend 1: Laser marking of ceramic circuits

These challenges come from new materials that need to be processed, as well as new applications that require services - each driving demand for growth and innovation, while shaping the market for laser system development.

For example, ceramics are one of the fastest developing materials in the field of laser processing, which is particularly important in semiconductor parts and circuit board manufacturing. Printed Circuit Board (PCB) is commonly referred to as the "mother of electronic system products" and is a component used in almost all electronic products. The small changes in PCB development have a significant impact on market trends.

In recent years, the focus of using ceramics in traditional printed circuit boards (PCBs) has shifted, and these circuit boards are made of plastic epoxy resins such as FP4. Compared with non ceramic PCBs, ceramic circuit boards have excellent heat treatment capabilities, are easy to implement, and provide excellent performance. However, many marking techniques, such as wire mesh processing, are not suitable for ceramics. The ink marking of ceramics is very troublesome, requires several consumables, and is not resistant to wear and tear. The brittleness and hardness of ceramics also make them one of the more difficult materials to label.

Therefore, in recent years, lasers have emerged as a substitute for ink printing technology, and many laser companies have developed systems that are particularly suitable for ceramic marking, such as diode pumped solid-state ultraviolet lasers and traditional CO2 lasers.

Trend 2: More flexible materials, shapes, and sizes

However, despite rapid development, ceramic markers in the electronic field are currently not the largest market for ES Precision. "For us, the largest industry is medical equipment," Andrew May said, "followed by automobiles, electronics, and general engineering components. The types of products required vary greatly depending on the industry and related industries."

The company has 8 laser systems (5 of which are Galv driven) to provide marking services for various application fields. Because of this, and also because the company always obtains new customers with customization needs - May emphasizes that for ES Precision, flexible capabilities are crucial.

Therefore, the laser it uses is suitable for marking different materials, shapes and sizes, as well as different batch sizes. The range of tags it can provide is as diverse as its customer base, and its laser can generate everything from code to graphics and data matrices - all of which are fast and highly reproducible.

Therefore, catering to this flexibility is necessary for laser marking machine manufacturers such as Bluhm Systeme. Antoinette Aufdermauer, the company's editor, stated that the company continuously monitors the market and develops its products accordingly.

Its marking system includes gas, fiber, and solid-state lasers, including CO2 and YAG systems. Laser marking is pulse type, with a working wavelength range of 0.355 μ M-10.6 μ M. Each type of laser has its own characteristics and some similarities: CO2 lasers can be used for marking plastics, rubber, paper, and foil; Fiber laser has advantages in marking steel and certain plastics; YAG lasers are suitable for marking metals and ceramics. Aufdermauer stated, "We conducted extensive testing on all materials of our clients in advance in the laser laboratory.".

Aufdermauer stated that portability is also crucial for ensuring the flexibility of laser marking operations, which is ideal for industrial customers. Therefore, Bluhm Systeme's latest product "Lightworx" is equipped with a 20W fiber laser in a compact workstation, which can be easily moved to the production environment. This system can create "permanent, sharp, anti-counterfeiting" markings on metals and plastics.

Trend 3: The demand for component traceability is increasing

Another important trend in the field of laser marking is to ensure and improve traceability - individual identification of products through unique identification marks on their surfaces. This type of marking can take various forms, but it is becoming increasingly popular and important to use data matrices, such as QR codes.

By labeling individual products with their unique data matrix codes, it is easy to identify their key details, such as manufacturer, batch number, and service life, in a non-invasive manner. This provides quality assurance: consumers and users can determine the exact source of the product. This quality assurance establishes a direct connection between consumers and manufacturers, and adds value to products, enabling them to compete with lower cost manufacturing.

Due to its incredible accuracy, lasers are very suitable for writing as small as 200 μ Detailed code for size m - so small that it cannot be seen by passersby, but if a person knows their location, it can be easily checked with a smartphone. At such a size, the data matrix can be used for anti-counterfeiting purposes, making it easy to check the authenticity of high-quality products in a non-invasive manner. This has had a huge impact on the pharmaceutical industry as it is a method of ensuring that drugs such as pills are not produced and distributed in fraudulent ways.

Component traceability also plays an important role as evidence in litigation. For example, if someone has undergone a medical transplant and the transplant fails, traceability allows them to know exactly where the problem occurred, where the problem occurred, and in which batch it occurred. This will certainly improve the efficiency of product recalls and other aspects, but it also gives customers more autonomy. This may not be obvious, but as society becomes increasingly interested in litigation, the technology that can enhance litigation judgments must also keep up.

Traceability has also promoted another trend in the entire manufacturing industry: improving environmental sustainability and reducing ecological impacts. By tracking products to understand when they fail or reach the end of their lifecycle, manufacturers can better proactively replace and recycle them. This also means that the product can be returned for refurbishment in the scheduled manner, so there may be fewer devices ultimately buried.

However, current data matrix labeling systems face many challenges. Certain materials make operations more difficult, especially glass and polymers, as well as thin metals and foils. The marking must also be permanent and stable, and the system must be able to adapt to various product sizes.

For some laser marking machines, a special challenge is to mark on non flat surfaces. In this field, the number of inkjet printers still exceeds that of laser based systems. Therefore, system engineers are working hard to overcome these challenges. For example, Laserax, a manufacturer of laser marking systems, offers carbon dioxide and fiber lasers with an average power of 20-500W and different cycle times, equipped with automatic focusing optical devices for 3D surfaces that can be adjusted according to the curvature of the object. In order to consider the surface with unknown geometry, Laserax's system uses an automatic focusing vision system, first scans the 3D surface, and then adjusts the laser focus during the marking process.

However, non flat surfaces are not the only challenge faced by laser marking system manufacturers. Dr. Florent Thibaut, CEO of QiOVA, a manufacturer of laser marking solutions, explained, "In many cases, standardized marking solutions (such as inkjet) are available globally." Unable to meet the specific labeling requirements for each product. Currently, laser is commonly used as a continuous method, similar to using a pen. However, this is not fast enough - we need to find a solution that can balance production volume and accuracy

The sequential marking is affected because laser marking must change according to the different products, so having a marking technique that can be adjusted according to each product is crucial. Manufacturers demand extremely high throughput - markings must adapt, marking rates must be high - even without considering the difficulty of processing certain materials such as glass or polymers.

To solve this problem, QiOVA applied for a patent for its VULQ1 technology, which won the Laser System Innovation Award in this year's Laser World Photonics Industrial Production Engineering. The technology did not choose to use a continuous beam of light (like traditional marking systems). On the contrary, it uses hundreds of beams of light to produce a stamp like effect - instantly generating the entire data matrix code. The method used to generate this unique imprint is dynamic beam shaping, which utilizes components such as spatial light modulators (SLMs). SLM can be adjusted based on each lens to create beams with unique structures.

Although other laser marking technologies may prioritize high repetition rates to achieve high production, QiOVA uses higher pulse energy and parallel processing to achieve better results.

Thibaut said, "This stamp like marking scheme unleashes enormous productivity potential for two-dimensional barcode marking and is easy to implement."

For example, its technology can be used for 570 μ The m-wide data matrix code marks PVC medical components at a speed of 77000 per hour. Other materials that the system can label include: aluminum coated with HDPE polymer; Alkali lime glass; Borosilicate glass, pure gold, and epoxy resin molded composite.

Thibault added, "The pattern size can be as small as 100." μ m. Simultaneously maintain perfect clarity and readability, even when marking straight lines, as all points are marked simultaneously More importantly, as it does not rely on high repetition rates, QiOVA can use ready-made infrared and green Nd: YAG lasers to construct the system, with a repetition rate of approximately 20-30Hz, ensuring that its system maintains cost-effectiveness as much as possible.

Trend 4: Ultra fast lasers turning glass into data storage

Another exciting new field of laser marking is data storage. Researchers claim that they can produce efficient data storage systems by encoding data into glass/crystal media using ultrafast lasers. The data is stored in the form of micro ablation in glass/crystals, and once generated, it can be stored for an astonishing amount of time,

In 2013, Hitachi announced the launch of its first quartz crystal data storage system; In 2014, researchers from the Optoelectronics Research Center (ORC) at the University of Southampton announced their development of a femtosecond laser etched glass system. ORC has started collaborating with Microsoft Research Institute on Project Silica, which promises to develop zb level storage systems and "fundamentally rethink how to build large-scale storage systems.".

However, writing on glass is not an easy task, as standard pulsed UV or CO2 laser systems can generate microcracks - excessive heating of the material surface can lead to damage at hot spots. Although this can be avoided by reducing pulse energy, it is not ideal when high precision is required. That's why researchers are turning to ultrafast (femtosecond) laser systems to minimize the risk of thermal damage. The ultra short duration of high-energy pulses ensures sufficient energy is transferred to the material, marked with extremely high accuracy, only producing the smallest heat affected zone and avoiding the generation of microcracks.

However, the current limitation of this technology is that the speed of data writing is extremely low, and writing Tb level data may take several years to complete. Fortunately, the ongoing breakthroughs are proposing methods to improve data writing speed. Last year, ORC researchers published an energy-efficient laser writing method in the journal Optica: this method is not only fast, but also can store approximately 500Tb of data on CD sized silica discs - they have a density 10000 times higher than that of Blu ray disc storage technology.