Science & Technology

New ways of observing laser interactions have the potential to improve laser-based manufacturing

(Lower left) The laser pierces the material. (Upper left) Measures the fluence of the laser. (Bottom right) Fluence and hole depth measurements are superimposed. (Upper right) Next, the relationship between these measurements is determined so that the hole depth can be calculated based solely on fluence. Credits: © 2021 Sakurai et al.

Despite decades of extensive research on lasers and their applications, there have been few accurate, efficient, and direct observations of the details of material interactions. For the first time, researchers have discovered a way to obtain such data from production lasers using low-cost equipment. This will Accuracy Of laser-cut or etched items. Given the widespread use of lasers, this can have a wide range of implications for laboratory, commercial, and industrial applications.

Lasers are used in a very wide range of applications in the modern world. One of the areas of increasing importance is manufacturing. The reason is that the level of accuracy with which a laser can operate is much higher than the accuracy of comparable physical tools. However, this level of accuracy could theoretically be even higher, leading to a new generation of technology that is still unimaginable. However, there are some hurdles to overcome. One of the key ways to improve the accuracy of a laser is whether there was a better way to get feedback on how the laser interacts with the material. This will give you better control over the cutting and etching behavior of the production laser and reduce uncertainty. This issue has proven to be surprisingly difficult to tackle.

“Measuring how deep a laser cuts into a surface often requires readings of tens or hundreds of depths, which is a major barrier to high-speed, automated laser-based production systems.” Said Professor Junji Yumoto of the Faculty of Physics, the University of Tokyo. “Therefore, we devised a new method of determining and predicting the depth of holes generated by laser pulses based on a single observation rather than tens or hundreds. This discovery is the controllability of laser machining. This is an important step forward in improving. “

Yumoto and his team figured out how to determine the depth of the laser hole using the least amount of information possible. This led them to look into what is known as the fluence of laser pulses. This is the light energy that the pulse provides to a particular area. Until recently, observing this fluence required expensive imaging equipment, which usually did not have sufficient resolution. However, thanks to developments in other areas of electronics and optics, the relatively simple Raspberry Pi Camera version 2 has proven to be sufficient for its job.

When their test laser device pierced the sapphire, the camera directly recorded the fluence distribution of the laser pulses. Next, the shape of the hole was measured with a laser microscope. The team superimposes these two results and uses some of the latest numerical techniques to create a large and reliable dataset that can accurately convey the relationship between fluence and hole depth. did.

“This corresponds to extracting about 250,000 data points from a single measurement,” says Yumoto. “Our new method can efficiently provide big data for machine learning and new numerical simulation methods to improve the accuracy and controllability of laser processing for manufacturing.”

Reference: “Direct correlation between local fluence and ablation morphology of single-pulse ultrashort laser” Haruyuki Sakurai, Kuniaki Konishi, Hiroharu Tamaru, Junji Yumoto, Makoto Kuwata, March 29, 2021 Correspondence material..
DOI: 10.1038 / s43246-021-00138-x

New ways of observing laser interactions have the potential to improve laser-based manufacturing New ways of observing laser interactions have the potential to improve laser-based manufacturing

Back to top button