Bliss Chapman

And as I mentioned, the size of the implantable system is limited by how you power the thing and get the data off of it. And at the end of the day, fundamentally, if you look at a human body, we're essentially a bag of salt water with some interesting proteins and chemicals, but it's mostly salt water that's very, very well temperature regulated at 37 degrees Celsius.

And we'll get into later why that's an extremely harsh environment for any electronics to survive, as I'm sure you've experienced, or maybe not experienced, dropping a cell phone in salt water in an ocean. It will instantly kill the device, right? But anyways, just in general, electromagnetic waves don't penetrate through this environment well. And just the speed of light, it is what it is.

And we'll get into later why that's an extremely harsh environment for any electronics to survive, as I'm sure you've experienced, or maybe not experienced, dropping a cell phone in salt water in an ocean. It will instantly kill the device, right? But anyways, just in general, electromagnetic waves don't penetrate through this environment well. And just the speed of light, it is what it is.

And we'll get into later why that's an extremely harsh environment for any electronics to survive, as I'm sure you've experienced, or maybe not experienced, dropping a cell phone in salt water in an ocean. It will instantly kill the device, right? But anyways, just in general, electromagnetic waves don't penetrate through this environment well. And just the speed of light, it is what it is.

We can't change it. And based on the wavelength at which you are interfacing with the device, the device just needs to be big. Like these inductors needs to be quite big. And the general good rule of thumb is that you want the wavefront to be roughly on the order of the size of the thing that you're interfacing with.

We can't change it. And based on the wavelength at which you are interfacing with the device, the device just needs to be big. Like these inductors needs to be quite big. And the general good rule of thumb is that you want the wavefront to be roughly on the order of the size of the thing that you're interfacing with.

We can't change it. And based on the wavelength at which you are interfacing with the device, the device just needs to be big. Like these inductors needs to be quite big. And the general good rule of thumb is that you want the wavefront to be roughly on the order of the size of the thing that you're interfacing with.

So an implantable system that is around 10 to 100 micron in dimension, in a volume, which is about the size of a neuron that you see in a human body, you would have to operate at hundreds of gigahertz, which... Number one, not only is it difficult to build electronics operating at those frequencies, but also the body just attenuates that very, very significantly.

So an implantable system that is around 10 to 100 micron in dimension, in a volume, which is about the size of a neuron that you see in a human body, you would have to operate at hundreds of gigahertz, which... Number one, not only is it difficult to build electronics operating at those frequencies, but also the body just attenuates that very, very significantly.

So an implantable system that is around 10 to 100 micron in dimension, in a volume, which is about the size of a neuron that you see in a human body, you would have to operate at hundreds of gigahertz, which... Number one, not only is it difficult to build electronics operating at those frequencies, but also the body just attenuates that very, very significantly.

So the interesting kind of insight of this ultrasound was the fact that ultrasound just travels a lot more effectively in the human body tissue compared to electromagnetic waves. And this is something that you encounter and I'm sure most people have encountered in their lives when you go to hospitals that are medical ultrasound sonograph.

So the interesting kind of insight of this ultrasound was the fact that ultrasound just travels a lot more effectively in the human body tissue compared to electromagnetic waves. And this is something that you encounter and I'm sure most people have encountered in their lives when you go to hospitals that are medical ultrasound sonograph.

So the interesting kind of insight of this ultrasound was the fact that ultrasound just travels a lot more effectively in the human body tissue compared to electromagnetic waves. And this is something that you encounter and I'm sure most people have encountered in their lives when you go to hospitals that are medical ultrasound sonograph.

And they go into very, very deep depth without attenuating too much of the signal. So All in all, you know, ultrasound, the fact that it travels through the body extremely well and the mechanism to which it travels to the body really well is that just the wave front is very different. It's electromagnetic waves are transverse. Whereas in ultrasound waves are compressive.

And they go into very, very deep depth without attenuating too much of the signal. So All in all, you know, ultrasound, the fact that it travels through the body extremely well and the mechanism to which it travels to the body really well is that just the wave front is very different. It's electromagnetic waves are transverse. Whereas in ultrasound waves are compressive.

And they go into very, very deep depth without attenuating too much of the signal. So All in all, you know, ultrasound, the fact that it travels through the body extremely well and the mechanism to which it travels to the body really well is that just the wave front is very different. It's electromagnetic waves are transverse. Whereas in ultrasound waves are compressive.

So it's just a completely different mode of, uh, wavefront propagation. Um, and as well as speed of sound is orders and orders of magnitude, less than speed of light, which means that even at 10 megahertz ultrasound wave, your wavefront ultimately is a very, very small wavelength. So if you're talking about interfacing with the 10 micron or a hundred micron type structure.

So it's just a completely different mode of, uh, wavefront propagation. Um, and as well as speed of sound is orders and orders of magnitude, less than speed of light, which means that even at 10 megahertz ultrasound wave, your wavefront ultimately is a very, very small wavelength. So if you're talking about interfacing with the 10 micron or a hundred micron type structure.

So it's just a completely different mode of, uh, wavefront propagation. Um, and as well as speed of sound is orders and orders of magnitude, less than speed of light, which means that even at 10 megahertz ultrasound wave, your wavefront ultimately is a very, very small wavelength. So if you're talking about interfacing with the 10 micron or a hundred micron type structure.

you would have 150 micron wavefront at 10 megahertz and building electronics at those frequencies are much, much easier and they're a lot more efficient. So the basic idea kind of was born out of using ultrasound as a mechanism for powering the device and then also getting data back. So now the question is, how do you get the data back?