Optical Filter Changer, Redesigned for Manufacturing

This is active work at QT Sense. The Quantum Nuova’s next design is confidential until it reaches the market in 2027, so this page has no drawings or photos. Other QT Sense work: the instrument enclosure and liquid handling.

The problem

The Quantum Nuova is QT Sense’s quantum-sensing instrument. It uses fluorescent nanodiamond sensors to measure stress in living cells in real time, for example how cells respond to different drugs. Its optical filter changer moves optical filters in and out of the light path.

The existing filter changer cost $350 per unit. It was a complex mechanism built around high-accuracy linear motion, and that complexity made it prone to failure.

Approach

The key was the requirement itself. When I worked through what the optics actually needed, the only accuracy constraint was that each filter lands within a few degrees of its position. The high-accuracy linear motion was solving a problem the instrument did not have.

So I rejected the precision linear mechanism and designed to the real requirement: a part cut from steel on an abrasive waterjet, driven by a simple DC motor with an encoder. The new design has fewer parts and uses standard processes, so it has far fewer ways to fail.

Results

Unit cost fell from $350 to $15, a reduction of about 96%, with the optical function preserved.

My contribution

I identified the few-degree accuracy requirement as the design constraint to build around, and led the redesign.