Non-destructive testing by stimulated electron emission capture
US4634868A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 17, 1984 |
| Grant date | Jan 6, 1987 |
| Priority date | — |
| Expiry date | Dec 17, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2223/633
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Non-invasive and non-destructive apparatus and method for imaging, recording, and comparing the mass density distributions and thicknesses of test specimens (19F, 19B). A source of medium-to-high-energy photons (3) directs a photon beam (4) at an electron source (17) comprised of high atomic number material, which emits in response thereto electrons (9F, 9B), some of which are not absorbed and not widely scattered by the test specimens (19F, 19B), but are transmitted therethrough and captured on one or more photographic films (15F, 15B) in contact with said specimens (19F, 19B). Net recorded film (15F, 15B) densities are in inverse relation to the mass density distribution of the corresponding test specimen (19F, 19B). A filter (5) is interposed between the photon source (3) and the capture film (15B) when back emission imaging (B) is employed. The filter (5) is optional when forward emission imaging (F) is used. The filter (5) absorbs photons (4) that have an energy sufficiently low to create an unwanted X-ray response on the capture film (15F, 15B) within the period required for the desired electron (9F, 9B) imaging.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.