Viewing posts for the category Ultrasensitive Instrument Design

Transcutaneous Blood Glucose: A War Story

Here at EOI we have two main kinds of project. One is normal client work, where we design and prototype custom instruments or parts of instruments, and the other is our internal technology development projects.  Some of our internal efforts fail, mostly because they tend to be insanely hard, but the ones that pay off give us important new capabilities.

Customer work almost always succeeds, and on the rare occasions when it doesn't, usually it's mostly because of client prevarication, such as cancelling an already-funded project for internal reasons. (In fairness, I've already posted a  project from 20 years ago that was more nearly 50:50.)  Here's an example of one of those, a transcutaneous (i.e. noninvasive) sensor for blood glucose and alcohol, to replace finger sticks and breathalyzers.  This one was really sad---folks have been working on that problem for 30 years, burning through mountains of cash, and mine is the only one I know of that actually worked.

The founder called me out of the blue at 3 PM on Christmas Eve, 2012. He turned out to be a charming and intelligent fellow with a lot of drive and not a lot of education, who was practically supernatural at raising money. He wanted me to build him an instrument, because that's what I do.

He'd patented the general principle, which avoided the individual physiological variations that usually bedevil those sorts of measurements. The idea was to use a hand cradle with a virtual pivot(*) holding a fibre bundle against the web of the first and second fingers. The location is perfect: there are two arteries very close to the surface, so you get to measure fresh blood instead of tissue fluid, and no one has hair, fat, or calluses there to get in the way. (The finger webs are also quite tender to the touch, so if you put a small-diameter pin there as well, you can prevent the user from pushing so hard that the arteries get squashed.)

Touch Panel Displays: Low-Cost Optical Front End

In cooperation with Flatfrog Laboratories AB, Lund, Sweden. This one was interesting mostly due to the requirement for high and stable performance at an absolute rock-bottom cost.

Plasmonic Nano-Antennas for Thermal Infrared Pixels

This was a seedling design study for a DARPA program that never got funded. It leveraged POEMS and my antenna-coupled tunnel junction devices, adding a couple of novel wrinkles: metal-insulator-metal varactors and parametric readout using a 10 GHz pump frequency. Hopefully there will be a chance to revisit this, because it was potentially a pretty sweet solution.

Long-range IR transceiver

For a large Far Eastern consumer electronics manufacturer to use in virtual reality games. A greatly improved transimpedance amplifier got them a factor of 10 in range (30 m vs. 3 m) for about the same amount of power.

Aircraft Carrier Flight Deck Optical Communications Link

Photon Budget and Optical Data Receiver
This one was a somewhat similar application for the Navy.