ISL Stage 7 Delivery

We ship to ION the devices shown below. There are ten Implantable Sensors with Lamp (A3030D) and fifteen Head Fixtures (A3024HF) of various types.


Figure: Batch ISL7 Deliverables. For a close-up of the A3030D see here.

Each ISL provides a 50-mm 915-MHz command antenna and a separate 30-mm 915-MHz data and acknowledgement antenna. The A3030D introduces support for longer interval lengths as well as random pulse generation. We need Version 4 of the ISL Controller Tool to command the A3030D. The new controller tool provides a version menu button to select between the A3030C and the A3030D. In other respects, the use and operation of the A3030D is identical to that of the A3030C we delivered in .


Figure: Output Power, Color, and Cannula Type for ISL7 Head Fixtures. We measure optical power with a photodiode and 40 mA LED current. All head fixtures are A3024HFC, except 7.1, which is A3024HFD.

The photograph below shows an example of the ISL7 head fixture with inclined silica cannula guide and cannula dummy installed.


Figure: Silica Guide Cannulas.

We ran out of cannula dummies and then silica guide cannulas during production of our fifteen head fixtures. Some we are shipping without cannula dummies. We run out of silica cannula guides and have no time to wait for more, so we use 10-mm steel cannula guides instead.


Figure: Steel Guide Cannulas.

We have been using silica guides because we believed they would transport less electrical noise into the brain. But our study of the sources of lamp activation noise suggests that a steel guide will cause no increase in lamp activation noise at the tip of the fiber. The guide will, however, affect the flow of the EEG signal in its neighborhood. We would like to learn from these three steel guides whether the silica guide is necessary or redundant.

We made twelve A3030Ds and all twelve are fully functional after encapsulation. The figure below shows all of them turning on at once in response to a multi-device XON command from our Command Transmitter.


Figure: Twelve A3030Ds Turning on Simultaneously.

We forgot to bind the X and L leads into pairs before we soldered them to our circuit boards. We bound the leads afterward encapsulation, which produced an unattractive finish on the previously smooth and rounded silicone-coated springs, as shown below.


Figure: Imperfect Silicone Binding in X and L Lead Pairs.

We believe there will be no problem implanting these lead pairs, not any compromise of their fatigue resistance due to the cosmetic problems with the finish.