Offner Imaging Spectrometers

Cassini Shield

Cassini Spacecraft


Cassini VIMS-V and VIMS-IR

The first Offner imaging spectrometer was the VIMS-V, which flew onboard the Cassini spacecraft. The instrument engineer for the VIMS-V was Dr. Francis Reininger, President of SPILAB. The VIMS-V was integrated with the VIMS-IR at JPL. The VIMS-V is shown here with the two red covers. It is positioned directly above the VIMS-IR, which is covered in gold MLI. One of the first spectral images captured at Saturn was the ring image that indicated grain-size and composition.


Click here for VIMS spectral images


Saturn Rings Grain

Spectral Images of Saturn Rings

Venus Express VIRTIS

Venus Express VIRTIS

Dr. Reininger was instrument engineer and optical designer of the VIRTIS, which combined the visible and infrared channels into one small instrument using a convex, dual band grating manufactured by Dr. Klaus Heidemann of Zeiss. The center of the grating diffracted the 250 - 1000 nm spectrum onto a CCD, and the outer annulus diffracted the 900 - 5500 nm spectrum onto a passively cooled, infrared detector array.


Click for Rosetta VIRTIS spectral images taken during Earth Flyby


VIRTIS grating

VIRTIS Convex Dual Band Grating

Offner in hand

Miniature Offner Imaging Spectrometer

SPILAB manufactured a palm sized Offner imaging spectrometer. The convex diffraction grating was manufactured by QUDOS Technology using electron beam milling. The spectrum was diffracted onto a CMOS detector array. A light source could be attached using a fiber optic cable.

Click these links to see spectra generated by the spectrometer:

Laser Diffraction Spectral-Image

Beer and Root Beer Spectra

Glass Filter Spectra

Laser Pointer Spectrum