Design of a compact wide-spectrum double-channel prism imaging spectrometer with freeform surface

Area of Science:

• Optics and Photonics
• Spectroscopy
• Space Science Instrumentation

Background:

• Imaging spectrometers are crucial for remote sensing and space exploration.
• Current spectrometers often face limitations in spectral range or resolution.

Purpose of the Study:

• To present a novel double-channel prism imaging spectrometer design.
• To achieve independent spectral resolution for both visible-near-infrared (VNIR) and shortwave-infrared (SWIR) bands within a single instrument.

Main Methods:

• Utilized double slits to divide the spectral band into two independent channels.
• Employed a beam splitter to direct light to separate VNIR and SWIR detectors.
• Incorporated a freeform surface mirror to correct for astigmatism across the wide spectral range.

Main Results:

• Designed an imaging spectrometer with a 30° field of view.
• Achieved a measured spectrum covering 400 nm to 2500 nm.
• Demonstrated compact size, cost-effectiveness, high performance, and minimal spectral distortion.

Conclusions:

• The developed double-channel spectrometer offers a unique solution for broadband spectral analysis.
• Its compact and high-performance design holds significant potential for future space exploration missions.
• Independent spectral resolution in VNIR and SWIR bands enhances data acquisition capabilities.