Coherent

Palo Alto's garage story belongs to Hewlett-Packard. Its laundry room story belongs to Coherent. In the summer of 1966 a group of engineers built a carbon dioxide laser in the laundry room of a house in Palo Alto and tested it by burning a spot on a neighbor's garage door. The company they formed grew into the largest laser maker in the world, with products in eye surgery, chip factories and research labs everywhere.

Coherent kept its headquarters in Palo Alto until 1992. This profile covers how it started, the Spectra-Physics and Varian connections, its growth and what became of it.

The laser comes to the Peninsula

The laser was new in the 1960s. The first one worked in 1960. Peninsula companies moved fast to build them. Spectra-Physics, founded in Mountain View in 1961, became one of the first laser makers. Stanford hired physicist Arthur Schawlow, a co-inventor of the laser concept, in 1961. He later shared the 1981 Nobel Prize in Physics for laser spectroscopy. Our page on Stanford's Nobel laureates covers him.

Coherent grew out of that scene. In a 2006 article for Laser Focus World marking the company's 40th anniversary, cofounder Eugene Watson wrote that the idea took shape in 1965, when Spectra-Physics management decided not to develop gas ion laser products. Watson was then sales and marketing manager at Spectra-Physics.

Founding in a laundry room, 1966

Coherent Radiation Laboratories was founded on May 26, 1966. Watson's account lists the team:

• Eugene Watson, the organizing founder, who came from Spectra-Physics sales and marketing.
• Jim Hobart, a laser scientist who also came from Spectra-Physics. Wikipedia lists him as the founder and he later led the company for years.
• Steven Jarrett, a laser scientist who had been Hobart's fellow graduate student at the University of Michigan.
• Wayne Mefferd, a mechanical engineer.
• Bob Rorden, an electronics engineer.

Earl Bell, a Spectra-Physics founder known for discovering the gas ion laser, agreed at first to join but withdrew. Sources disagree on the founder count, with some giving six names.

The company moved into Watson's house in Palo Alto. He set up a laser development lab in his laundry room because it had running water and 220 volt power. Watson wrote that startup money came from his sale of $20,000 in Varian stock. Other company histories give startup capital of about $10,000. Either way, the link to Varian, Palo Alto's microwave tube company, is a nice detail. We do not publish the address of the house, which is a private residence.

The first carbon dioxide laser

That summer Hobart built a carbon dioxide laser in the laundry room. To prove it worked, the team aimed the beam at a neighbor's garage door. "The growing, darkening, smoking spot proved that the beam was coherent," Watson wrote. Company histories call it the first commercially available carbon dioxide laser. Wikipedia notes that sources conflict. Hobart himself credited PerkinElmer with the first commercial laser of that kind.

Boeing's manufacturing research lab in Seattle became the first customer in the fall of 1966. Hobart installed the laser there in January 1967. DuPont signed a contract for a 100 watt carbon dioxide laser and two krypton ion lasers, with an option to invest. DuPont passed on the investment. The Rockefeller family's investment group, the predecessor of Venrock, put in money instead. Wikipedia gives $250,000 from the Rockefellers in 1967 and another $250,000 from other investors the next year.

Growth in Palo Alto

Coherent moved well beyond carbon dioxide lasers. It made ion lasers for research labs and small argon green lasers used in eye surgery. By the 1990s medical lasers made up half its revenue. In 1981 it bought the scientific division of the German excimer laser maker Lambda Physik. In the early 1980s a joint venture with General Electric, Coherent General, released an industrial laser that had problems; the venture was sold off in 1993.

Growth brought trouble too. After Hobart stepped back from day to day management, the company struggled with defective products, late deliveries and poor manufacturing efficiency. He returned as chief executive in August 1988 and introduced Japanese style methods such as just in time manufacturing. Wikipedia reports that productivity rose 60 percent while costs fell 58 percent. A 1992 analyst quoted in company histories said Coherent had "more Ph.D.s on staff than most competitors have employees."

Researchers at Coherent also worked with Stanford. Bernard Couillaud, who later ran the company, developed the Hänsch and Couillaud method of laser frequency stabilization with Theodor Hänsch, then a Stanford professor and later a Nobel laureate.

The move to Santa Clara, 1992

In 1992 Coherent bought a 200,000 square foot building in Santa Clara for $7.5 million and moved its headquarters out of Palo Alto, according to company histories. We could not confirm the street address of its Palo Alto plant from official sources, so we do not give one. After the move:

• 1995. Coherent bought the laser diode operations of Uniphase and other diode businesses, forming a semiconductor group.
• July 1996. Couillaud became chief executive. Hobart left the next year.
• 2003. Coherent acquired the rest of Lambda Physik, whose ultraviolet lasers were used in making flat panel displays.
• From 2004. During John Ambroseo's years as chief executive, revenue grew from about $400 million to almost $2 billion, partly through acquisitions such as Excel Technology (2006) and Rofin-Sinar (agreed in 2016).
• July 2022. II-VI Incorporated completed its purchase of Coherent and took the Coherent name.

Coherent today

The combined company, Coherent Corp., is headquartered in Saxonburg, Pennsylvania, at the old II-VI base north of Pittsburgh. It makes lasers, optical parts and materials for communications, industrial and other markets. Nothing marks Coherent's Palo Alto beginnings. The founding house is a private home. We could not confirm what occupies the company's former Palo Alto plant.

Lasers in Palo Alto today

Laser work did not leave Palo Alto with Coherent. Stanford's physics and applied physics departments remain major laser research centers, building on the work of Schawlow and Hänsch. The biggest laser in the area is at SLAC National Accelerator Laboratory, on Stanford land just west of Palo Alto. Its Linac Coherent Light Source, an X-ray laser, first lased in April 2009 and lets scientists film chemical reactions and see the structure of proteins. SLAC runs free public tours, covered in our SLAC visitor guide.

For more on the region's hardware pioneers, see our Silicon Valley history, the page on Shockley, Fairchild and the semiconductor boom and the companies hub. The HP Garage is the city's best known startup landmark if you want to see a founding site from the sidewalk.

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