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OP/author here, I also have patella tendinitis since I dislocated my patella when I was 17. This is the reason I started looking at ultrasounds, I figured that

OP/author here, I also have patella tendinitis since I dislocated my patella when I was 17. This is the reason I started looking at ultrasounds, I figured that I could buy one for the $160 cost to get a scan from a doctor. I have looked around for a cheap ultrasound, but $1100 is far cheaper than I was able to find (I got to about $3k but looked like a dodgy dealer so didn't link to it). But 1k is still way more expensive than I think it should be. It should be a sensor you just plug into and iphone for a few hundred. I mean there is the http://www.thermal.com/thermal-cameras/ http://www.thermal.com/thermal-cameras/ thermal camera for only $250, why not ultrasound? Making a photo sensor must be thousands of times more complicated than ultrasounds sensors. I just want to know why I can't buy one cheaper than my massively more complex iphone :)

sithadmin 11y ago
>Making a photo sensor must be thousands of times more complicated than ultrasounds sensors. Cheaper thermal imaging sensors like that usually use a very, very low resolution sensor for picking up thermal data, then use interpolation to map the low-resolution data onto a high-resolution image provided by a higher-res conventional camera sensor. Obviously, this approach won't work with ultrasound tech, as there wouldn't be a secondary high-resolution data source.
- grahar64 11y ago
  In the post there is a link to a paper where someone used a 40x40 array for 3d ultrasound imaging and there is a 64x array at 35MHz used for high resolution imaging of things like eyes. That is pretty low resolution for such interesting applications. Imagine the applications for a high resolution 3D ultrasound scanner combined with a high-resolution camera.
  - gene-h 11y ago
    It might be helpful to elaborate on what applications a 3d ultrasound scanner would have.
  - conceit 11y ago
    A 40x40 ultrasound array can scan with a much better resolution, look at prenatal imaging for example. The phased array is modulated in the time and space domains, so one cell can substitute many fixed ones. With the speed of sound, the receivers resolution of depth information extracted from a reflection's timing information would be a million times better. ...
    - conceit 11y ago
      I'm not sure I would understand my own description, let me go again: The transducer sends a modulated signal and receives the reflections. From the time difference information is gained. The signal is steered using beamforming as known from radar technology. This creates many different impulses that can be correlated from the received reflections. The key is that the 1600 sells deliver more than one input over time, from a nonstatic signal, which is like shooting photos from different perspectives. I believe cell correlation or whatchamacallit is done in all kinds of variation for CCD data, too.
toomuchtodo 11y ago
> I just want to know why I can't buy one cheaper than my massively more complex iphone :) Size of market for iPhones compared to size of market for iPhone ultrasound devices. Also, you'll need FDA approval in the US for their use.
- grahar64 11y ago
  Size of market is a chicken and egg problem, if they were cheaper, the market could grow, and get more cheaper. Also FDA would only regulate for medical use, it could be sold for educational use to remove the regulations.
  - jes 11y ago
    With respect, I think you're speculating here. For example, the FDA and other agencies are concerned with the effects of transmitting energy into the human body. Medical devices like ultrasound systems are not toys. I don't mean to be harsh at all, but with respect, I question your assertions here.
    - grahar64 11y ago
      It would be interesting to see, I mean the argument is that my head phones don't need FDA approval and they can damage my hearing if I turn them up too loud. But some kind of limits would be important to ensure safety. And this post is a question because I don't know the answer, so I am just guessing (a lot). I hope someone with actual experience in getting FDA approval for a medical ultrasound machine actually reads it and answers, with how much it cost and what hoops they had to jump through.
      - ska 11y ago
        If my previous comment is not enough detail I'll happily expand.
      - jes 11y ago
        I have worked in the medical device industry building ultrasound systems for twenty years. In general, there are thousands of regulations that must be satisfied. Some specifications that must be met include ISO 13485, ISO 14971, IEC 60601 3rd Edition, IEC 62304, and probably ten more that I have forgotten about, such as RoHS, WEE, radiated emissions, etc. The systems I worked with involved multilayer (16 layers plus) circuit boards, custom ASICs, FPGAs, ARM SOCs, etc., mixed OS (e.g., Windows CE and WindRiver, etc.) The code base is large and complex, as you have not just ultrasound, but often, calculation packages of various kinds (cardiac, OB, etc.) These packages are expensive to develop and have to be carefully verified. If you're measuring the length of a fetal femur and translating the measured length to an estimated gestational age, you don't wish to be wrong. Same deal with cardiac output measurements, etc. Then there is the whole issue of transducers. It's a complex field, and you have to deal not only with materials (some of which contain RoHS regulated elements, such as lead), but also, dicing saws (to cut the piezo), matching layers, transmission lines (to send signals to / from the transducer and the ultrasound machine front end.) I'm not trying to be rude, or baffle you with a lot of jargon, it's just that my experience is that building a useful ultrasound machine is much more complex than it might appear from the outside of the industry, so to speak. Finally, I think building an iPhone is probably even more complex, but the incredible volume of sales tends to make amortizing the cost more palatable. I could be wrong, of course, and your comments are welcome.
sosborn 11y ago
Used ultrasounds can be had for good prices: https://www.dotmed.com/equipment/2/4/all/ https://www.dotmed.com/equipment/2/4/all/
semi-extrinsic 11y ago
With the math on transducer costs, you've basically answered the question. However, aliexpress will get you 2MHz transducers 10x cheaper if you buy them in bulk. Then of course you have to worry about dodgy chinese website component quality. I also think you're seriously underestimating the computational cost of converting the measured signal to a usable image. No way is an RPi fast enough to produce a live image with decent quality. There are quite a few papers in the literature about using high-end GPUs to speed up ultrasound imaging and denoising, for commercial vendors I'm guessing it's custom ASIC territory.
- gherkin0 11y ago
  > I also think you're seriously underestimating the computational cost of converting the measured signal to a usable image. No way is an RPi fast enough to produce a live image with decent quality. There are quite a few papers in the literature about using high-end GPUs to speed up ultrasound imaging and denoising, for commercial vendors I'm guessing it's custom ASIC territory. Really? Medical ultrasound has a long history predating high-end GPUs. Maybe that kind of computing power is required for modern high-resolution/low-lag devices, but my guess is you could get something usable with a computer as powerful as a RPi. http://www.ob-ultrasound.net/history1.html http://www.ob-ultrasound.net/history1.html
  - daemin 11y ago
    I can confirm that you can turn ultrasound data into a 2D image using a simple mid 2000's era ARM processor and an FPGA. So a RPi can even be overkill for that purpose.
- outworlder 11y ago
  But basic ultrasound machines have been with us for decades. From a quick check, since the sixties! I have no hard data yet, but I would be surprised if a Pi couldn't do it. 3D scans are another matter, but this is a thread about low cost scanners, so that's out of the picture.
gene-h 11y ago
part of the reason thermal cameras are cheap and ultrasounds are not is that thermal cameras have consumer uses. One can use thermal cameras for hunting or determining home energy efficiency, an ultrasound can pretty much only be used for medicine. Although, consumer sonar for fishing(which operates at lower frequencies) is still fairly expensive[0]. Second, your estimate on the price of PZT elements is not necessarily realistic as the transducer is rather large(22 mm in diameter). A 10X10 array would be impractically large. One can buy PCB mount piezo elements for motors for cents per element in bulk[1]. It might even be possible to modify one of those expensive components into an array as was done in this homemade STM[2]. Although in both cases there are bound to be issues with impedance matching and potentially changes in resonant frequency. [0] http://www.westmarine.com/sonar http://www.westmarine.com/sonar [1] http://pcbmotor.com/applications-and-solutions/smd-piezo-components/ http://pcbmotor.com/applications-and-solutions/smd-piezo-com... [2] http://dberard.com/home-built-stm/ http://dberard.com/home-built-stm/
tim333 11y ago
There are various ones for about 1k on ebay eg. http://www.ebay.com/itm/A-Portable-Digital-Ultrasound-Scanner-Machine-System-3-5-Mhz-Convex-Probe-3D-/201522624091?hash=item2eebaf365b:g:jS4AAOSwT~9Wlxuc http://www.ebay.com/itm/A-Portable-Digital-Ultrasound-Scanne... Don't know if that'd the kind of thing or too basic?
datenwolf 11y ago
> Making a photo sensor must be thousands of times more complicated than ultrasounds sensors. What makes you think that? Photo sensors have no moving parts, photons are the carriers of the electromagnetic force, so they readily interface with electronics given the right interface material; any semiconductor material with a matching bandgap will do, photons interacting with a bandgap produces free charge carriers; this is exactly what you're after. The rest is chipscale manufacturing, i.e. lots of sensor cells in a repetetive pattern. You can easily mass produce that in large quantities using photolithography methods, yet even if your process were to bad, that you'd get a low yield it would still be profitable. Ultrasound on the other hand is acoustics, i.e. mechanical waves. So you're dealing with moving parts, mechanics. Transducers are discrete parts, they can't (yet) be manufactured at chip scale. They're ceramics, and there are lot of parameters that go into manufacturing ceramics which limit the amount that can be produced in a single batch. And then you've to deal with electronics that's not over waaay beyond your typical hobbist level; it's in fact so complex that it goes over the head of most professional electrical engineers and there are companies who are specialised in ultrasonics transducer electronics consulting, doing the difficult design work for the large brand names.

sithadmin 11y ago

>Making a photo sensor must be thousands of times more complicated than ultrasounds sensors. Cheaper thermal imaging sensors like that usually use a very, very low resolution sensor for picking up thermal data, then use interpolation to map the low-resolution data onto a high-resolution image provided by a higher-res conventional camera sensor. Obviously, this approach won't work with ultrasound tech, as there wouldn't be a secondary high-resolution data source.

grahar64 11y ago
In the post there is a link to a paper where someone used a 40x40 array for 3d ultrasound imaging and there is a 64x array at 35MHz used for high resolution imaging of things like eyes. That is pretty low resolution for such interesting applications. Imagine the applications for a high resolution 3D ultrasound scanner combined with a high-resolution camera.
- gene-h 11y ago
  It might be helpful to elaborate on what applications a 3d ultrasound scanner would have.
- conceit 11y ago
  A 40x40 ultrasound array can scan with a much better resolution, look at prenatal imaging for example. The phased array is modulated in the time and space domains, so one cell can substitute many fixed ones. With the speed of sound, the receivers resolution of depth information extracted from a reflection's timing information would be a million times better. ...
  - conceit 11y ago
    I'm not sure I would understand my own description, let me go again: The transducer sends a modulated signal and receives the reflections. From the time difference information is gained. The signal is steered using beamforming as known from radar technology. This creates many different impulses that can be correlated from the received reflections. The key is that the 1600 sells deliver more than one input over time, from a nonstatic signal, which is like shooting photos from different perspectives. I believe cell correlation or whatchamacallit is done in all kinds of variation for CCD data, too.

toomuchtodo 11y ago

> I just want to know why I can't buy one cheaper than my massively more complex iphone :) Size of market for iPhones compared to size of market for iPhone ultrasound devices. Also, you'll need FDA approval in the US for their use.

grahar64 11y ago
Size of market is a chicken and egg problem, if they were cheaper, the market could grow, and get more cheaper. Also FDA would only regulate for medical use, it could be sold for educational use to remove the regulations.
- jes 11y ago
  With respect, I think you're speculating here. For example, the FDA and other agencies are concerned with the effects of transmitting energy into the human body. Medical devices like ultrasound systems are not toys. I don't mean to be harsh at all, but with respect, I question your assertions here.
  - grahar64 11y ago
    It would be interesting to see, I mean the argument is that my head phones don't need FDA approval and they can damage my hearing if I turn them up too loud. But some kind of limits would be important to ensure safety. And this post is a question because I don't know the answer, so I am just guessing (a lot). I hope someone with actual experience in getting FDA approval for a medical ultrasound machine actually reads it and answers, with how much it cost and what hoops they had to jump through.
    - ska 11y ago
      If my previous comment is not enough detail I'll happily expand.
    - jes 11y ago
      I have worked in the medical device industry building ultrasound systems for twenty years. In general, there are thousands of regulations that must be satisfied. Some specifications that must be met include ISO 13485, ISO 14971, IEC 60601 3rd Edition, IEC 62304, and probably ten more that I have forgotten about, such as RoHS, WEE, radiated emissions, etc. The systems I worked with involved multilayer (16 layers plus) circuit boards, custom ASICs, FPGAs, ARM SOCs, etc., mixed OS (e.g., Windows CE and WindRiver, etc.) The code base is large and complex, as you have not just ultrasound, but often, calculation packages of various kinds (cardiac, OB, etc.) These packages are expensive to develop and have to be carefully verified. If you're measuring the length of a fetal femur and translating the measured length to an estimated gestational age, you don't wish to be wrong. Same deal with cardiac output measurements, etc. Then there is the whole issue of transducers. It's a complex field, and you have to deal not only with materials (some of which contain RoHS regulated elements, such as lead), but also, dicing saws (to cut the piezo), matching layers, transmission lines (to send signals to / from the transducer and the ultrasound machine front end.) I'm not trying to be rude, or baffle you with a lot of jargon, it's just that my experience is that building a useful ultrasound machine is much more complex than it might appear from the outside of the industry, so to speak. Finally, I think building an iPhone is probably even more complex, but the incredible volume of sales tends to make amortizing the cost more palatable. I could be wrong, of course, and your comments are welcome.

sosborn 11y ago

Used ultrasounds can be had for good prices: https://www.dotmed.com/equipment/2/4/all/ https://www.dotmed.com/equipment/2/4/all/

semi-extrinsic 11y ago

With the math on transducer costs, you've basically answered the question. However, aliexpress will get you 2MHz transducers 10x cheaper if you buy them in bulk. Then of course you have to worry about dodgy chinese website component quality. I also think you're seriously underestimating the computational cost of converting the measured signal to a usable image. No way is an RPi fast enough to produce a live image with decent quality. There are quite a few papers in the literature about using high-end GPUs to speed up ultrasound imaging and denoising, for commercial vendors I'm guessing it's custom ASIC territory.

gherkin0 11y ago
> I also think you're seriously underestimating the computational cost of converting the measured signal to a usable image. No way is an RPi fast enough to produce a live image with decent quality. There are quite a few papers in the literature about using high-end GPUs to speed up ultrasound imaging and denoising, for commercial vendors I'm guessing it's custom ASIC territory. Really? Medical ultrasound has a long history predating high-end GPUs. Maybe that kind of computing power is required for modern high-resolution/low-lag devices, but my guess is you could get something usable with a computer as powerful as a RPi. http://www.ob-ultrasound.net/history1.html http://www.ob-ultrasound.net/history1.html
- daemin 11y ago
  I can confirm that you can turn ultrasound data into a 2D image using a simple mid 2000's era ARM processor and an FPGA. So a RPi can even be overkill for that purpose.
outworlder 11y ago
But basic ultrasound machines have been with us for decades. From a quick check, since the sixties! I have no hard data yet, but I would be surprised if a Pi couldn't do it. 3D scans are another matter, but this is a thread about low cost scanners, so that's out of the picture.

gene-h 11y ago

part of the reason thermal cameras are cheap and ultrasounds are not is that thermal cameras have consumer uses. One can use thermal cameras for hunting or determining home energy efficiency, an ultrasound can pretty much only be used for medicine. Although, consumer sonar for fishing(which operates at lower frequencies) is still fairly expensive[0]. Second, your estimate on the price of PZT elements is not necessarily realistic as the transducer is rather large(22 mm in diameter). A 10X10 array would be impractically large. One can buy PCB mount piezo elements for motors for cents per element in bulk[1]. It might even be possible to modify one of those expensive components into an array as was done in this homemade STM[2]. Although in both cases there are bound to be issues with impedance matching and potentially changes in resonant frequency. [0] http://www.westmarine.com/sonar http://www.westmarine.com/sonar [1] http://pcbmotor.com/applications-and-solutions/smd-piezo-components/ http://pcbmotor.com/applications-and-solutions/smd-piezo-com... [2] http://dberard.com/home-built-stm/ http://dberard.com/home-built-stm/

tim333 11y ago

There are various ones for about 1k on ebay eg. http://www.ebay.com/itm/A-Portable-Digital-Ultrasound-Scanner-Machine-System-3-5-Mhz-Convex-Probe-3D-/201522624091?hash=item2eebaf365b:g:jS4AAOSwT~9Wlxuc http://www.ebay.com/itm/A-Portable-Digital-Ultrasound-Scanne... Don't know if that'd the kind of thing or too basic?

datenwolf 11y ago

> Making a photo sensor must be thousands of times more complicated than ultrasounds sensors. What makes you think that? Photo sensors have no moving parts, photons are the carriers of the electromagnetic force, so they readily interface with electronics given the right interface material; any semiconductor material with a matching bandgap will do, photons interacting with a bandgap produces free charge carriers; this is exactly what you're after. The rest is chipscale manufacturing, i.e. lots of sensor cells in a repetetive pattern. You can easily mass produce that in large quantities using photolithography methods, yet even if your process were to bad, that you'd get a low yield it would still be profitable. Ultrasound on the other hand is acoustics, i.e. mechanical waves. So you're dealing with moving parts, mechanics. Transducers are discrete parts, they can't (yet) be manufactured at chip scale. They're ceramics, and there are lot of parameters that go into manufacturing ceramics which limit the amount that can be produced in a single batch. And then you've to deal with electronics that's not over waaay beyond your typical hobbist level; it's in fact so complex that it goes over the head of most professional electrical engineers and there are companies who are specialised in ultrasonics transducer electronics consulting, doing the difficult design work for the large brand names.