A technique passed down from hand to hand

As a Nikon Master Craftsperson, Mr. Mizutani trains the next generation of technicians as well as devoting himself to improving his own technique.

When he instructs a technician on eliminating bubbles (as part of the process of cementing optical glass), he first teaches the trainee how to vary the pressure applied by pressing a cork on the back of the trainee's hand. Next, the technician presses the cork on the back of Mr. Mizutani's hand, while Mr. Mizutani evaluates the way in which he varies the pressure, saying "a bit harder" or "that's just about right." The technician is made to learn this technique by carrying out this operation repeatedly and developing a feel for it. It really is passed down "hand-to-hand." This is the best way to learn a craft, says Mr. Mizutani.

"I'd like to train as many of the next generation as possible myself," he says, adding that "publicizing the way in which the technique of cementing optical glass is being passed on and the very existence of the technique itself is my job as a Nikon Master Craftsperson."

The successors whom Mr. Mizutani has taken in hand and trained are now tackling the process of cementing lenses for high-precision optical systems.

The cementing of lenses is also being carried out at overseas production sites. Thus, technicians in other countries are also inheriting the techniques of the Japanese craftsman.