The customer develops and manufactures diagnostic and surgical devices for ophthalmology. In eye laser treatments, a curved flap is cut in the toplayer of the cornea and pulled back. This flap was previously cut with an oscillating knife. The company wanted to use a femtosecond laser for this task. In the treatment, the ophthalmologist fixes the eye in place with a flexible handpiece using a vacuum. The base device deflects the laser beam through a swivelling arm into the handpiece and focuses it there. An ultra-precise X-Y deflection creates the cutting geometry. Zuhlke’s task was to develop the device and design the system.
As a first step in the project, Zuhlke examined the technical feasibility of the undertaking. In order to verify the major risks early on, ideas and concepts were elaborated upon and implemented in a functional model with the handpiece and articulated arm. Initial cutting trials yielded very positive results. The findings were incorporated directly into the design specifications. Within a year, the mechanics, electronics and software were ready for the first prototype. The FDA had assigned the device software to the highest security class, so an independent security system was required. The prototype was then tested for the first time in clinical trials on patients. The objectives of achieving thinner cuts of greater precision and shortening the surgical time were both met. After further optimisations, the device became a series product.