Hamamatsu News 1 / 2018

News 2018 Vol. 1 10 Highly rated by end users even from the early developmental stage So you have completed a beam-homogenizing optical system for DDL optimized for laser hardening. What can you offer customers with this system from now on? Matsuura: Our current beam-homogenizing optical system (A14132 series) is designed to attach to the second-generation DDL L11585 series. The L11585 series is available in two types: a 2 kW and a 4 kW type. We will propose combining our beam homogenizer with a 2 kW type for users who don’t need high power, and combining with a 4 kW type for users who need high power. Omiya: One outstanding feature of our beam-homogenizing optical system is that the users themselves can select a beam pattern accord­ ing to their applications. For example, our lineup includes 5 aspect ratio converter units from 1:1 to 1:5, and 4 types of condenser lenses. This combination of both converter units and lenses allows selecting up to 20 beam patterns. Users can easily swap aspect ratio converter units and condenser lenses as needed to match the processing task. Uchiyama: We are also developing a coaxial unit with temperature monitoring and a visible guide light unit which can be attached as an option. Besides standard beam patterns we also welcome custom requests for even larger beam patterns. How was the customer response? Omiya: We displayed product samples at a domestic laser-related exhibition held in April, 2017 and got a much better response than expected. Even though the products were still in the developmental stage, we got high ratings from end users and also from system integrators who specialize in building up on the DDL to offer their customers a complete system. We were very happy to receive such positive feedback at such an early stage of development. Uchiyama: Unlike conventional techniques such as induction harden­ ing, laser hardening causes almost no warping or distortion during hardening and requires no cooling. We propose that our customers use our beam-homogenizing DDL as a new, high-stability light source for laser hardening. Laser hardening has many advantages, for example, it does not need any post-processing, and therefore will offer users an eco-friendly process. R&D Interview Matsuura: DDL uniformly radiates homogenized light. By making use of this feature, we can find a wide range of applications for DDL in addition to laser hardening such as laser cladding, wafer surface heat treatment in semiconductor manufacturing, and pumping for solid- state lasers. Establishing this new technique to create new markets What are your plans moving forward? Uchiyama: Many customers are requesting us to shorten the tact or cycle time by irradiating laser light over an even larger surface area. This requires higher output power than the present level. To respond to this request, we have started working on improving the power ratings of our beam-homogenizing optical system. At the same time, to boost output power, we intend to further increase the output from the current 4 kW type DDL. Omiya: The laser hardening technique is not yet popular and few people know that there are now lasers ideally suited for laser harden­ ing. Usually, it takes time for a new processing technique to become widely known, especially since the reliability rating method differs from conventional techniques. Uchiyama: When hardening the gear of a mechanical part normally subject to wear, the entire gear is hardened by the conventional technique and the reliability is defined based on processing results for the entire gear. However, the actual portion subject to wear is only the gear teeth. So quality can be verified if the gear teeth are properly hardened. Laser hardening is effective enough to harden gear teeth. However, the current definition of reliability established for the conventional technique acts as a barrier that prevents companies from using laser hardening which only processes the gear teeth. To spread use of laser hardening, we think it is essential to review these quality standards. Miyajima: Moving forward we plan to verify what type of laser hardening is most ideal in terms of laser power, beam pattern, and size of processed objects. To achieve this we will work with our users and system integrators in a long process of trial and error, which will enable us to firmly establish our new laser hardening processing technique.