Phuc G Tran

US Patent:

6909094, Jun 21, 2005

Filed:

Feb 12, 2003

Appl. No.:

10/365029

Inventors:

Phuc G. Tran - Richmond VA, US
Kenneth H. Shafer - Sutherland VA, US

Assignee:

Philip Norris USA Inc. - Richmond VA

International Classification:

G01J005/08

US Classification:

2503411, 250340, 250330

Abstract:

A system and method for THz imaging utilizing a single THz detector that detects an image of a large area and provides good spatial details (high resolution). In one aspect, the THz beam passes through an object to be imaged, and a THz fiber bundle having a plurality of THz fibers collect the THz beam on the other side of the object and transmit the beams to a single THz detector. Each THz fiber imparts a different time delay to the beam traveling therein. Therefore, the spatial information is converted into time information in the form of time delays. Knowing the distance each part of the imaging area must travel (hence the time it takes) before reaching the THz detector, one can recover the spatial information from the time data. In another aspect, the THz fiber bundle is replaced with a mask having an array of holes with each hole having a different depth or a different refractive index. In still another aspect, the THz fiber array is replaced with a plate holding different masks.

US Patent:

6909095, Jun 21, 2005

Filed:

Jun 4, 2003

Appl. No.:

10/454152

Inventors:

Phuc G. Tran - Richmond VA, US
Kenneth H. Shafer - Sutherland VA, US

Assignee:

Philip Morris USA Inc. - Richmond VA

International Classification:

G01J005/08

US Classification:

2503411, 250340, 250330

Abstract:

A system and method for THz imaging utilizing a single THz detector that detects an image of a large area and provides good spatial details (high resolution). In one aspect, the system can individually modulate a different pixel of an image. The system could be a series of masks. Each mask may include holes that may be turned on/off with a distinct pattern from all of the other holes. Once the data for each mask has been received, the data for each hole may be extracted according to its modulation pattern. Another modulation system may include a micro-mirror array that deflects the THz signal towards or away from the THz detector.