Magnetometer patent

[Göran]

Hi. Has anybody read the United States Patent No 6,496,005 B2? You can find it on Geotech under Magnetometers/Patent. I understand some of it, but do anybody have an answer to:

1. What is the function of the coil (#102)
2. Can this thing operate at earth mag. field?
3. The fixed transmission frequency w1 (#115)is supposed to be "clearly spaced" from the proton resonant frequence. How much is "clearly spaced"?

In my wiue this magnetometer, at least in part, works like an HF SSB (SingelSideBand) Tranceiver in the sence that you have a carrier frequency that is being modulated by another signal (The resonance freq.of the proton)and as a result producing the carrier and two signals that is +/- the proton frequency. Then you filter out one of the sidebands and the carrier and you are left with the SSB signal. The original proton frequency can be restord (demodulated) by adding the carrier once again as a beat frequency.

Am I right so far??

[Joe Geller]

Re: Magnetometer patent

This looks like a device for medical NMR. There the fields are typically in the kiloGauss range, as opposed to the .5 Gauss Earth's field. Also see his later published patent US 20010043065 at uspto.gov.

coil 102 in combination with static field 105 create the field Bm in which all measurements are made. The transmission signal B1 is 1,000 times smaller than Bm suggesting the medical type application. (col. 3, lines 26-2.

It is probably not suitable for Earth's field's measurements at around .5 Gauss.

The URL below is to an unrelated Siemens web publication that introduces Dr. Heid. His email address shows up on Google, why not write to him?



Click Here

[Göran]

Re: Magnetometer patent

Thanks Joe for your reply.
You are probably right that this device is for some sort of medical NMR. The inventor works for siemens and they have MRI equipment
But in the patent he speeks of measuring changeing magnetic fields rather than doing spectroscopy or imaging like in medical applications. That might indicate that he is speaking of a magnetometer rather than medical NMR/MRI. But he seems to use a similar way of recreateing the FID-signal as one or more echoes as one does in MRI ("The 180 degrees phase shift of the transmission signal leads to a phase synchronization....")
Still, a can´t understand what the coil 102 does. Maybe its current is part of a locking loop??

[Joe Geller]

Re: Magnetometer patent

The US 20010043065 published application issued as the '005 patent. They are the same. You can see the history of the US prosecution at the uspto "Public PAIR" page, but unfortunately the file history hasn't been scanned in for this application, so you only see the events and dates, not the actual filings as you can see for later published applications (before publication, the prosecution history is confidential).

I'll re-read it and see if I can shed any more light on the operation of coil 102.

I notice that Dr. Heid's email address is hot linked in the past URL reference. Since the patent has already issued (and is in the public domain) he might be willing to have a brief conversation directly with you. You never know, some inventors maintain silence beyond their patent disclosures, others are happy to discuss the invention, once public.



USPTO Public PAIR (to see the events of the application process for an application number)