CALIENT Technologies

Move the light, not the fiber

Leadership Team

Arjun Gupta
Executive Chairman and CEO

Arjun Gupta is the Executive Chairman at CALIENT and has been the key investor in CALIENT for two decades. In addition, Arjun is the Chief Believer and founder of Telesoft Partners (, a special situations venture capital firm in Silicon Valley. Over the last twenty‑five years, he has invested in and helped build over 100+ technology companies, of which over 60+ companies have been acquired or gone public (combined market cap over $750 billion). Recognizable brands include DocuSign,, T-Mobile USA, Uber and others. He was on the Forbes Midas List of Top-100 Venture Investors in 2006, 2007, 2008, 2009. Prior to Telesoft, Arjun was at McKinsey & Company where his clients included Apple, AT&T/PacBell, Verizon/PacTel and others. He was part of the Digital Transition Project for LA which launched Qualcomm CMDA against the industry standard of TDMA. He was also part of the Paradigm Project which led to the spinoff of General Magic from Apple. He started his career at Tektronix Inc, initially as an operating systems software engineer, then a field applications engineer and finally a product specialist covering new product introductions in the US, Germany and Japan. Arjun loves developing and scaling great technology products.

In 2001, Arjun launched a family foundation to support education, conservation and the performing arts. The foundation has supported over 100 projects in America, India and Africa. Arjun is a Trustee of Aspen Institute and the Aspen Music Festival. He is a co-founder and co-chair of YPO Gold Aspen. Arjun is an avid outdoorsman and has skied to the North Pole and to the South Pole and was recently appointed a UN Mountain Partnership Ambassador to help with climate change initiatives. Since 2013, Arjun has been a member of the new ownership group of the Sacramento Kings NBA basketball team.

Arjun received his MBA from Stanford University, an MS and BS (Phi Beta Kappa) in computer science from WSU, and a BA (Honors) in economics from St Stephen’s College (India). He is an ALI Fellow at Harvard University and a Henry Crown Fellow at the Aspen Institute. Arjun lives in San Francisco and Aspen.

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Dr. James Armstrong
President of Calient Technologies

James has overall responsibility for leading Calient’s business as it develops innovative solutions in MEMS−based optical circuit switches for software defined networks and data centers.

James has developed his career in the technology sector, most recently working for Spirent Communications from 2014-2018, where he held the positions of Chief Operating Officer and Executive Vice President of Products, and Executive Vice President and General Manager of the Networks and Applications Division. Prior to Spirent, James worked for Symmetricom, Inc. where from 2006-2013 he held positions of Chief Technology Officer, Executive Vice President and General Manager of the Communications division, and Vice President of Engineering of the Communications division.  Prior to Symmetricom, James has also held various executive and engineering management positions with Movidis, DIVA Systems and Sarnoff Corporation.

James earned a BSc degree in Electrical Engineering from Princeton University and a Doctorate degree in Electrical Engineering from Purdue University.

Dr. Kevin Welsh
President Operations and Calient Fellow

Dr. Welsh has responsibility for CALIENT world-wide manufacturing activities, including manufacturing, product delivery, quality and reliability.  Kevin has over 20 years experience as a manufacturing and operations executive with demonstrated leadership and communication skills.   His broad operations management experience includes MEMS and wafer processing techniques, new product introductions, and manufacturing and test engineering.  Kevin has a proven track record in recruiting and retaining highly successful and enthusiastic teams that are focused on results and execution.

Kevin began his career at IBM’s Advanced Technology Center in East Fishkill, New York where he developed new materials and processes for semiconductor photolithography. After IBM he worked for Seagate and, later, Applied Magnetics where he developed processes for the fabrication of magnetoresistive and giant magnetoresistive recording heads. Kevin has a Ph.D. in Chemistry from the University of Wisconsin and served as a postdoctoral research scientist at Columbia University.

Rick Santos

Rick is responsible for all things financial and brings over 20 years of corporate finance, M&A, and international financial management experience with both public and privately-held companies in the technology sectors. Rick is a seasoned financial leader who brings a wealth of experience in the areas of capital raising, M&A and strategic finance initiatives, with proven track record managing finance teams, growth and operational excellence. Prior to joining CALIENT, Rick has held CFO and executive financial management positions with a variety of technology companies, including, Digilens, Powervation (acquired by Rohm Co., Ltd.), Validity Sensors (acquired by Synaptics NSDQ: SYNA), Intel Corporation, VxTel (acquired by Intel NSDQ: INTC), and Exar Corporation (NSDQ: EXAR). Rick began his career with Deloitte & Touche where he spent 8 years supporting audit and assurance engagements from their Silicon Valley office.  Rick holds a BS degree in business administration from Humboldt State University and is a member of the AICPA.

Simon Evans
CTO Software

Simon heads up Calient’s software development team. He is a graduate of Computer Engineering with Honors from Melbourne University, including one year at the University of California, Irvine studying opto-electronics, semiconductor physics, and research at the Beckman Laser Center under Brian Wong. He has worked in the computer industry for 20 years, with a focus on enterprise software and business process.

Following university, Simon worked for 8 years in California software startups, getting involved in coding, design, release process, dev ops, software development process, and sales engineering. He returned to Australia in 2006 as an Enterprise Software consultant for 8 years. Simon moved to San Francisco as VP of Software Engineering at Nexant Inc for 5 years, to help implement clean energy programs across North American Utilities.

Dr. Roger Hajjar
Senior Advisor, Products and Engineering

Since 2005, Dr. Hajjar has pioneered Laser Phosphor Display (LPD) technology, working with businesspeople and technologists in a variety of disciplines — both in the U.S. and around the globe. Dr. Hajjar has registered more than 100 U.S. and worldwide patents and has a long history of success in taking optical-based technologies from inception to high-volume manufacturing.

Prior to Prysm, Dr. Hajjar served as Vice President/GM of Transmission Subsystems with Avanex Corporation and Vice President of Technology with Vitesse Semiconductor. Dr. Hajjar was Chief Technology Officer and founder of Versatile Optical Networks prior to its acquisition by Vitesse, and later, by Avanex. Dr. Hajjar held management positions with TeraStor Corporation and the Eastman Kodak Company. He also held research positions at the Optical Sciences Center at the University of Arizona and IBM’s T.J. Watson Research Center.

He was recently honored with the prestigious 2016 Adele De Berri Pioneers of AV Award.

Dr. Hajjar holds a PhD and MS in Optical Sciences from the University of Arizona, as well as a BS in Electrical Engineering from Boston University, from where he graduated Summa Cum Laude.

Dr. Kumar Ganapathy
Senior Advisor, Products and Engineering

Dr. Kumar Ganapathy is a serial entrepreneur and founder of Enterprise Labs, a startup “foundry” focused on the Enterprise Cloud infrastructure in Silicon Valley.Kumar has founded two successful start-ups over the past 20 years across Telecom and Enterprise IT infrastructure : (a) VxTel for high-density VOIP gateways (1998-2001, acquired by Intel), and (b) Virident for Server-side high-performance flash storage for enterprises (2006-2013, acquired by Western Digital). His startups have raised over $200M of funding from top-tier VC firms and were acquired for a combined net worth of over $1.2 billion. Prior to his entrepreneurial career, Kumar was Principal Engineer and Fellow of Conexant and Rockwell Semiconductor leading the development of 56-kbit modems and GSM phones. He is a recognized leader in Storage, DSP, and Wireless technologies with over 75 patents and 12 technical publications. He is an active angel investor especially for impact startups in India working to drive societal change thru entrepreneurship.

Kumar has received his Ph.D from University of Illinois at Urbana Champaign (UIUC), MS from University of Massachusetts at Amherst, and B.Tech from Indian Institute of Technology at Chennai. He is the recipient of the Distinguished Alumnus Award from IIT Madras, Fellow of Conexant/Rockwell, and Siemens Gold medal winner at IIT.