Upconverting and time-gated two-dimensional infrared transillumination imaging
US5451785A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 18, 1994 |
| Grant date | Sep 19, 1995 |
| Priority date | — |
| Expiry date | Mar 18, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/39
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for direct two-dimensional transillumination imaging of a sample immersed in or including a scattering medium at infrared to near-infrared wavelengths. Frequency conversion and time-gating techniques in the infrared and near-infrared range are used to enhance two-dimensional image collection and detection. The apparatus includes a probe radiation source for applying a probe beam in the infrared to near-infrared frequency range to the sample. The probe beam is spread to cover a two-dimensionally extending area of the sample to be imaged. After interacting with the sample, the probe beam is representative of a two-dimensional image of the covered sample area. In one embodiment the apparatus includes a time-gating arrangement for selecting a temporal portion of the probe beam in a narrow time window representative of early arriving photons transmitted through the scattering medium and providing a time-gated beam representative of the two-dimensional image of the sample area. A reference beam interacts with a nonlinear medium to shift the frequency of the probe beam to a different frequency, which may lie outside the infrared to near-infrared range. In many appli…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.