Zemax Software Holdings, a global provider of optical and illumination design software, has been acquired by EQT Partners, a leading investment firm with portfolio companies in Europe, Asia, and the U.S., and with total sales of more than €19 billion ($22 billion) and approximately 110,000 employees. EQT acquired Zemax from Arlington Capital Partners, a private equity firm based in Washington, D.C. “Our partnership with Arlington has been a tremendous success," said Zemax CEO Mark Nicholson, who will continue in his leadership role at Zemax. "During their ownership, Zemax made substantial investments and demonstrated consistent strong organic growth." “As we enter our next stage of growth, we are pleased to partner with EQT as we continue to expand our product offerings and deepen our customer focus," Nicholson said. "EQT’s relationships, global presence, and investment philosophy position Zemax to enter into a new phase of investment and growth that stays true to our vision to offer software based on a strong physics architecture, uphold a culture of excellence and innovation and drive customer success.” Zemax’s virtual prototyping tools enable the efficient, accurate design of optical components for a variety of industries and for products ranging from space telescopes to smartphone cameras to biomedical imaging devices. EQT will leverage its global network and experience in scaling businesses to support the continued growth of Zemax. “EQT’s software expertise and international presence will help Zemax further expand its product offering, both organically and through acquisitions, to best serve its global customer base,” said Brendan Scollans, partner at EQT Partners and investment advisor to EQT. Financial terms of the agreement were not disclosed.