Scientific Solutions Inc. (SSI) has developed a tunable liquid crystal Fabry-Perot (LCFP) etalon system comprised of a resolving and a suppression etalon in tandem. The 30-micron resonant cavity spacing of the resolving etalon provides for high spectral resolution while the system maintains the significantly broader free spectral range of the 6-micron gap suppression etalon across the tunable region. An applied electric field alters the ordinary refractive index of nematic liquid crystal cells within each etalon cavity, thereby
altering the resonant properties of the etalons, allowing for system tunability over several orders of interference. This system acts as a tunable optical filter with an operating range from 700nm to 1100nm.
Testing of the LCFP etalon system with both a high resolution Czerny-Turner monochrometer and a stabilized ND:Yag laser demonstrate a FWHM of 0.67nm to 1.03nm. System transmission reaching 70% of polarized light is achieved with tunability over one free spectral range in approximately 30 milliseconds. The free spectral range of the tandem etalon system ranges from 27nm-36nm over the operating range, and
allows for 40 randomly selectable spectral channels per free spectral range. This system is designed for use in spectral imaging systems, initially for the semiconductor industry, but is equally applicable to the earth remote sensing community.
To take advantage of the large luminosity-resolution product of the Fabry-Pérot interferometer used in tandem with modest-aperture telescopes, a Fabry-Pérot interferometer has been developed that is widely adaptable to a variety of extended source observations. The instrument is designed for adaptability across a range of optical and near-IR (NIR) spectral lines from 550 to 1100 nm, which are characterized by a wide range of velocity distributions of the emitting species. The system features a twin-étalon configuration to provide an extended free spectral range and to enhance contrast when observations include bright reflected solar or twilight backgrounds. Although the optical path and all the optical elements of the system are readily accessible, the instrument is ruggedized for transportability and extended remote field operation once it is optically configured. State-of-the-art, modularly adaptable, proven detectors (GaAs photomultipliers, large CCDs, and germanium integrating detectors) are featured to optimize instrument sensitivity. Recently, a series of NIR observations were made at the Millstone Hill Incoherent Scatter Radar Facility, Westford, Massachusetts, in a single-étalon mode.
To take advantage of the large luminosity-resolution product of the Fabry-Perot interferometer used in tandem with modest aperture telescopes, a Fabry-Perot interferometer has been developed that is widely adaptable to a variety of extended source observations. The instrument is designed for adaptability across a range of optical and near infrared spectral lines from 550 nm to 1,100 nm, which are characterized by a wide range of velocity distributions of the emitting species. The system features twin etalon configuration to provide extended free spectral range and to enhance contrast when observations include bright reflected solar or twilight backgrounds. Although the optical path and all optical elements of the system are readily accessible, the instrument is ruggedized for transportability and extended remote field operation once optically configured. State-of-the-art, but proven detectors (GaAs photomultipliers, large charge coupled devices, and Ge-Nitride integrating detectors) are featured to optimize instrument sensitivity, and are modularly adaptable.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.