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4D Technology Corp., co-founded by one of the University of ÃÛèÖÖ±²¥â€™s most renowned optical scientists, developed entirely new optical instruments for NASA to measure the surfaces of mirrors and other critical components on the Webb, which was launched into space on Christmas Day after more than two decades of development.

While most of 4D’s work for the space telescope was finished nearly a decade ago, the long-delayed launch was an exciting moment, said Neal Brock, a co-founder of the company who stepped into a role as technical consultant to 4D after it was acquired by a larger company in 2018.

“We hadn’t thought about it in quite awhile, it was little over year ago they were talking about it and then there was another delay,� Brock said, recalling watching Webb’s launch. “It was a bit nerve wracking, when it launched, until it got up and they shed the outer cone from the telescope.�

“I think it will still be a little tense until images come back,� said James Millerd, a 4D co-founder and technical consultant to the company since retiring as president and chief technology officer last year.

Problem solving

As NASA began developing the Webb as the Next Generation Space Telescope in the late 1990s, new methods were needed to rapidly measure the surfaces of Webb’s system of multiple mirrors which form its primary light-gathering mirror, as well as other structures, to ensure they will perform amid environmental vibrations and in temperatures near 400 degrees below zero in the vacuum of space.

Webb’s primary mirror is made of 18 separate, hexagonal mirror segments mounted on a main panel, and two panels folded for launch and deployed in space. The mirrors are mounted on actuators to move them to change focus.

Enter 4D Technology, which was co-founded in 2002 as a spinoff of a California company by renowned UA optics professor emeritus James Wyant, retired first dean of what is now the UA’s James C. Wyant College of Optical Sciences.

Wyant, a pioneer in the optics-based measurement technology known as interferometry, invested in the company and brought it to ÃÛèÖÖ±²¥ with principals Millerd and Brock to form 4D.

The company’s technology is a form of interferometry, which essentially compares waves of laser light reflected off a reference material and the subject surface and gauges the difference when the waves are combined.

4D has developed so-called “dynamic� interferometers that can take readings in as little as a millionth of a second — making them immune to the effects of vibration and environmental noise.

That got NASA’s attention.

“The first system we built delivered was to them,� Millerd said.

“They were trying to build these large beryllium mirrors that become the segments, and they had to measure them under cryo-vacuum conditions inside a large vacuum chamber,� he said. “The whole thing was shaking and vibrating, and we had this snapshot technology that could measure them down to nanometers, which is what they needed.�

Over more than a decade of work with NASA and prime Webb contractor Northrop Grumman, 4D developed several new technologies just for the project.

“All the different tests they needed to do, they all needed this dynamic capability, but not one type of interferometer would work,� Brock said. “So we had to develop and sometimes invent ways to make interferometers do what they wanted, but they all incorporated our dynamic technology.�

One breakthrough came when 4D adapted its technology to multiple wavelengths for the Webb, he recalled.

“We came with a way to make it work, and it ended up being a big improvement in our dynamic phase sensor,� Brock said.

Millerd said the company developed different interferometers to measure the mirror shapes, the carbon-fiber backing structures and the alignment of the mirror segments, in super-cold cryogenic conditions.

4D had delivered most of its Webb hardware to NASA or its prime contractor, Northrop Grumman, by 2012, he said.

When Webb entered its final test phase a few years ago, 4D was brought in to upgrade some of the computer systems and to support testing.

Meanwhile, NASA and its contractors have used the 4D instruments on other projects including ground-based telescopes and the UA-led OSIRIS-REx mission to extract samples from an asteroid in 2020, Millerd said.

Wider uses

With Webb still under development, 4D rolled out a number of interferometry products and got financial backing to grow the company, which employs about 60 people at its longtime location in an industrial park on ÃÛèÖÖ±²¥â€™s south side.

4D’s interferometer technology has found wide uses in aerospace applications, for customers besides NASA including major defense contractors Raytheon, L3 Harris Technologies, Lockheed Martin and Northrop Grumman, which was the prime contractor on the Webb telescope.

The company’s optical metrology instruments are in demand wherever there is a need for super-precise surface measurements and, besides aerospace and defense, have found uses in a broad array of industries including semiconductor, automotive and biomedical manufacturing.

4D also offers a line of industrial measurement instruments, including handheld models used to inspect critical parts for surface imperfections.

Millerd noted that a major application for its InSpec line of portable surface measuring devices is inspection of surfaces of aircraft turbine engines, which must go through annual inspections.

“Up until now, these inspections were done with flashlights and skilled operators trying to figure it out,� he said. “Now we can actually measure it with a handheld instrument.�

Back to its roots

4D is also going back to its roots, in a way, to serve the semiconductor industry with devices to precisely measure the surfaces of silicon wafers, for example.

Brock and Millerd noted that the company was initially focused on developing surface-measurement tools for computer chipmakers before it began working with NASA.

The company has since developed several products for semiconductor manufacturing, including its NanoCam to measure the surface of microscopic components, Millerd noted.

4D’s acquisition a few years ago by a company that primarily serves the semiconductor industry has only helped its marketing to that sector.

In 2018, 4D was acquired by California-based Nanometrics Inc. in a deal worth $40 million. Nanometrics later merged with Rudolph Technologies to form Onto Innovation, based near Boston.

“It does give us access to more semiconductor markets,� Millerd said. “They have very high demands in terms of service, and it’s challenging to go after that as a smaller company.�

Onto has kept 4D’s ÃÛèÖÖ±²¥ operation intact, and the company continues to grow, said Millerd, who was replaced as head of the local operation by Erik Novak, an eight-year veteran of the company named general manager last February.

“This last year was the best year ever, though the pandemic was a setback for everyone,� Millerd said.