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World's Tiniest Radiometer To Power Medical Scanner

Posted by timothy on from the good-weekend-for-it dept.

BuzzSkyline writes "University of Texas physicists have built the world's smallest radiometer. The minuscule radiometer is only 2 millimeters across and operates on the same principles as the common light-driven toy, which consists of spinning black and white vanes in a partially evacuated bulb. The researchers attached a mirror to their tiny radiometer and used it to rapidly scan a laser beam. Their hope is that they will be able to incorporate the radiometer into catheters to drive scanners that produce medical images of the interiors of blood vessels and organs. The devices would replace micromotors in conventional catheter-based scanners, eliminating the need to run potentially risky electrical currents into the body."

11 of 37 comments (clear)

  1. Powered via a cable by thms · · Score: 3, Insightful

    At first this "Because there's obviously no sunlight in the body, this light-mill pulls its power from a laser run up through the center of the catheter." seemed rather silly. When you already have a cable why not use that to get all the power you want? But later on the articles mentions that blood vessels really don't like anything above one volt. Other generators/motors (applying an alternating external magnetic field maybe) produce too much voltage already, so producing the power via photons is a safe alternative.

    On a related note, I wonder how far the tech for burning blood sugar in a fuel cell is, that would allow for long independent operation of tiny devices and since nothing rotates should scale low wrt. voltage

    1. Re:Powered via a cable by causality · · Score: 4, Funny

      At first this "Because there's obviously no sunlight in the body, this light-mill pulls its power from a laser run up through the center of the catheter." seemed rather silly. When you already have a cable why not use that to get all the power you want? But later on the articles mentions that blood vessels really don't like anything above one volt.

      So by reading the fine article you answered your own question.

      --
      It is a miracle that curiosity survives formal education. - Einstein
    2. Re:Powered via a cable by Sulphur · · Score: 2, Funny

      This points out a need to revise the expression "where the sun doesn't shine."

    3. Re:Powered via a cable by kurokame · · Score: 2, Interesting

      At first this "Because there's obviously no sunlight in the body, this light-mill pulls its power from a laser run up through the center of the catheter." seemed rather silly. When you already have a cable why not use that to get all the power you want? But later on the articles mentions that blood vessels really don't like anything above one volt.

      Also, the optical approach means that the concept can be adapted for use while the patient is inside an MRI. Wire-free is often handy when you're building neat toys for medical use.

      I'm sad though, everyone seems to have missed the best line. This new device is a power source, right?

      ... he hopes the micromotor will eventually find uses in cancer imaging.

      "It has yet to realize its full potential," said Condit.

      Get it? Get it? Oh, c'mon, the pun wasn't THAT bad...

  2. But they're NOT radiometers! by Ancient_Hacker · · Score: 5, Informative

    The "common toy" is not a radiometer. It's a heat engine. The bulb is only partially evacuated and the hotter, black side of the vanes heats up the gas molecules, which then bounce off it with increased vigor, compared to the white side. So the vanes spin with the white side going forward.

    A true radiometer would be bouncing photons off the white side, and spinning with the black side leading.

    The heat-engine version has many times the efficiency of the photon one.

     

    1. Re:But they're NOT radiometers! by chgros · · Score: 4, Informative

      This led me to look at the wikipedia article for "radiometer".
      A radiometer measures the strength of the radiation; whether the measurable effect is caused by heat or anything else is not relevant as long as it's proportional to the quantity being measured; in that sense the common toy *is* a radiometer.
      As for the reason it moves, it turns out it's more complicated than that.

  3. Re:Smallest radiometer? Not at all. by BuzzSkyline · · Score: 3, Funny

    They meant a Crookes Radiometer.

  4. But... by EdIII · · Score: 2, Interesting

    eliminating the need to run potentially risky electrical currents into the body.

    But.. But.. The fine folks at Taser International Inc say there is no risk!

    I'm confused.

  5. Pass the lube... by fahrbot-bot · · Score: 3, Funny

    The devices would replace micromotors in conventional catheter-based scanners, eliminating the need to run potentially risky electrical currents into the body.

    You had me at "catheter" and "electrical current".

    --
    It must have been something you assimilated. . . .
    1. Re:Pass the lube... by Like2Byte · · Score: 2, Funny

      The devices would replace micromotors in conventional catheter-based scanners, eliminating the need to run potentially risky electrical currents into the body.

      You had me at "catheter" and "electrical current".

      If that's what you're in to. They had me at "replace".

  6. Re:a spinning, laser powered catheter? by BuzzSkyline · · Score: 2, Informative

    It does, literally, spin. Look at the video.