Spectroscopic imaging device employing imaging quality spectral filters

US5528368A · kind A · utility

Assignee

• The United States of America, as represented by the Department of Health and Human Services · US

Inventors

• Edgar N. Lewis · Brookeville, US
• Ira Levin · Seattle, US
• Patrick J. Treado · Pittsburgh, US

Key dates

• Filing date: Dec 23, 1994
• Grant date: Jun 18, 1996
• Expiry date: Dec 23, 2014

Classification

• Technology area (CPC G): Physics
• CPC primary: G01J3/2823
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Techniques for providing spectroscopic imaging integrates an acousto-optic tunable filter (AOTF), or an interferometer, and a focal plane array detector. In operation, wavelength selectivity is provided by the AOTF or the interferometer. A focal plane array detector is used as the imaging detector in both cases. Operation within the ultraviolet, visible, near-infrared (NIR) spectral regions, and into the infrared spectral region, is achieved. The techniques can be used in absorption spectroscopy and emission spectroscopy. Spectroscopic images with a spectral resolution of a few nanometers and a spatial resolution of about a micron, are collected rapidly using the AOTF. Higher spectral resolution images are recorded at lower speeds using the interferometer. The AOTF technique uses entirely solid-state components and requires no moving parts. Alternatively, the interferometer technique employs either a step-scan interferometer or a continuously modulated interferometer.