Blue Semiconductor Lasers Expand New Possibilities in Micro Processing
In the winter of 2015, Shimadzu's BLUE IMPACT™ fiber-coupled high-brightness blue direct diode laser received the "CHO" MONODZUKURI Innovative Parts and Components Award that awards prizes for advanced technology in Japan.
BLUE IMPACT™ is expected to contribute to the expansion of many different industries, not only laser processing. Developing BLUE IMPACT™ required the ideas of a particular new engineer at Shimadzu, as well as the cultivated technology and skills accumulated over many years in Shimadzu's Device Department.
Too-Elaborate Design Drawings
In 2013, this was the opinion of the Sensor Device Business Unit of Shimadzu's Device Department on being handed the design drawings.
Said Jiro Saikawa, the Manager of the Unit that created those drawings. As yet, no one knew the substantial impact these drawings would have in one year after being developed into a product.
Saikawa was a new senior hire at Shimadzu. He had spent many years in a public research institution studying ways of creating lasers at various wavelengths. He was an uncommon case of a researcher nearing forty years-of-age not yet tired of basic research who left his public institution and moved to Shimadzu to use his accumulated knowledge and create laser devices. The first project he undertook from scratch was a fiber-coupled high-brightness blue direct diode laser, which would eventually be sold under the name BLUE IMPACT™. Saikawa completed his design drawings in high spirits since to him they contained everything needed by such a laser. However, being research-minded, he lacked the foresight of the need to turn his design into a product suitable for end users, resulting in a laser that was too elaborate in design and function. This was the important perspective Saikawa's boss wanted to impart when he told Saikawa, "It's clumsy."
Taking on a New Market
Laser devices are essential components in manufacturing products, whether they be laser processing machines, illuminations, displays, medical instruments, light sources for solid-state laser excitation, or physical and chemical scientific research. Laser devices are one of the key products of Shimadzu's Device Department, which supplies a variety of laser light sources and wavelength conversion devices for measuring instruments, and has created a well-established reputation for itself both within and outside Shimadzu. In 2012, the idea of entering a new market gained momentum inside the Department. This idea was to become BLUE IMPACT™, the development of which was entrusted to Saikawa.
Attention within the Device Department fell on the market for next generation lasers used in laser processing. Laser processing not only avoids the frictional wear and degradation at cut surfaces caused by conventional cutting instruments, but it is also capable of micro-sized processing barely visible to the naked eye by reducing the laser spot size (laser beam diameter). Thanks to these attributes, the prominence of laser processing has grown in semiconductor LSI fabrication in the trend of ongoing miniaturization of microchips, as well as in any industry that requires micro processing. Most of the laser light used to date has been infrared light. This light can be used to process iron and stainless steel without difficulty, but red metals such as gold and copper needed for electronic circuit design absorb almost no infrared laser light. This makes it difficult to process these metals without moving to high power outputs. However, gold and copper have the blue laser light absorption rate one order higher than that of infrared laser light. The Department focused its efforts in this area.
There was one particular hurdle to overcome. Single blue light semiconductor lasers generally had low beam power output, and increasing power output also increases beam size, which made it difficult to increase power output while maintaining small spot size. Resolving this problem would contribute to the semiconductor industry and various industries that use micro processing.
The technique chosen to resolve this problem was laser combining, which uses lenses to combine the beams of multiple blue light sources into optical fiber. Outputting the laser from optical fiber not only improved device handling, but also makes it easy to increase laser power output by joining together multiple laser units.
"Bring Expertise Together"
Developing the product was going to be difficult, but Saikawa already had assistance in the form of a group of strong allies.
"Shimadzu's Device Department gathers together experts in a variety of component technologies. One person specializes in optical coatings, one person knows about laser assembly, another knows electrical engineering, another mechanical engineering...walking down the hallway is like visiting a small factory town that contains the best of Japan's expertise in advanced technology. I was surprised to find a place like this when I first started working at Shimadzu. Everyone was confident in each other's abilities, and with the help of these experienced professionals I strongly believed that any problem could be overcome. It was thanks to their help that this development project succeeded."
Thus Saikawa gathered together the necessary component technologies, and overcame repeated knockbacks to complete his design drawings. In the following year (2013), he received the go ahead to turn the drawings into a new product.
To Be Part of a Solution
Two years after the project started, the BLUE IMPACT™ blue direct diode laser was completed by collecting the combined expertise of Shimadzu's Device Department. The idea of a highly bright and highly efficient blue light laser soon attracted interest, and since launch there has been no sign of any end to inquiries for the product. In 2015, the outstanding knock-on effect of BLUE IMPACT™ on technology and industry was recognized formally and BLUE IMPACT™ was awarded the highest 2015 "CHO" MONODZUKURI Innovative Parts and Components Award by Nikkan Kogyo Shimbun and MONODZUKURI Nippon Conference.
"I was uncertain how much recognition BLUE IMPACT™ would get, and was very happy to see orders coming in from companies in a variety of industries. In the future, I want to create more accessible laser devices that solve manufacturing problems throughout the world."
Adding knowledge of the latest in laser technology has further enhanced the developmental abilities of Shimadzu's Device Department.
Mr. Jiro Saikawa, Manager, PhD (physics)
Sensor Device Business Unit, Device Department
* Affiliates and titles of the persons in this article are current as of the time of interviewing.