The glass inside a camera lens determines everything from the image’s focus to flares — Nikon’s Nikkor lens division recently shared an inside look at how the lenses are made, or more specifically, how the glass inside those lenses is crafted.
The glass originates from the Kikari Glass Company in Akita, Japan, which is located on the northern end of Japan’s main island of Honshu. The area is known for its clean air and water — and for the hospitality of its people.
The Kikari glass plant is one of only a few facilities producing optical glass, according to the video, and one of even fewer that complete the entire process of crafting every optical element themselves. The Nikkor plant doesn’t just design lens glass — the company also designs and assembles the equipment that it uses to make the glass.
The engineers and craftsmen at the plant adhere to strict specifications to keep quality consistent from one Nikkor lens to the next. Even at the very first stage of creating the glass, any imperfections will become obvious errors in the final product, so the plant uses strict regulations and repeated quality checks at multiple stages of the process.
The refractive index, or the shape of the lens that determines exactly how the light passes through, plays a significant role in the function of the final product. At the Kikari plant, the refractive index is guaranteed down to six decimal points to achieve that accuracy across multiple lenses.
“We are always working to maintain quality through precise measurement and careful inspection so that all users of Nikkor lenses are able to capture the perfect moment,” said Akiko Kimura, a member of the production division at Kikari Glass.
Manufacturing conditions at every step of the process can also play a role in the final product, leading the team to collaborate along each step of the process, with the glass craftsmen working closely with the design engineers, for example.
The video is the sixth installment in the Philosophy of Nikkor series exploring the company’s lens division.