Logging device loaded with dielectric material to minimize spurious transverse magnetic mode components
US4603297A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 23, 1983 |
| Grant date | Jul 29, 1986 |
| Priority date | — |
| Expiry date | Aug 23, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The disclosure is applicable to a borehole logging device of the type which includes an elongated body suspendable in a borehole and having at least one transmitting antenna and at least one receiving antenna mounted in spaced relation in the body. Energizing signals are applied to the transmitting antenna to produce electromagnetic energy, a portion of which is received at the receiving antenna after being affected by earth formations surrounding the borehole. In accordance with the disclosed invention, a region of the body is loaded with a dielectric material having a dielectric constant selected to minimize, at the receiving antenna, the effect of spurious transverse magnetic mode components of standing wave electromagnetic energy within the body. Preferably, the dielectric material is selected to have a dielectric constant which adjusts the wavelength of the spurious transverse magnetic mode components of standing wave electromagnetic energy such that the standing wave has substantially a minimum amplitude at the receiving antenna. In an illustrated embodiment, a dielectric material is loaded in the region between the receiving antenna and a conductive end cap proximate thereto…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.