A coma-free super-high resolution optical spectrometer using 44 high dispersion sub-gratings

Area of Science:

• Optical Engineering
• Spectroscopy
• Instrumentation

Background:

• Traditional Czerny-Turner spectrometers suffer from coma aberration, limiting spectral resolution.
• Achieving high spectral resolution and zero aberration simultaneously is a significant challenge in optical instrument design.

Purpose of the Study:

• To experimentally demonstrate a novel super-high spectral resolution optical spectrometer with zero coma aberration.
• To showcase the capabilities of a new spectrometer design for diverse spectral sensing applications.

Main Methods:

• Utilized a compound integrated diffraction grating module with 44 high dispersion sub-gratings.
• Employed a two-dimensional backside-illuminated charge-coupled device array photodetector for detection.
• Configured a zero-off-axis spectrometer design.

Main Results:

• Achieved a spectral resolution of 0.005 nm (5 pm) in the ultraviolet range.
• Obtained a spectral resolution of 0.01 nm in the visible range.
• Demonstrated uniform diffraction efficiency across a broad 200 nm to 1000 nm wavelength region.

Conclusions:

• The demonstrated spectrometer offers unprecedented spectral resolution and zero coma aberration.
• The novel zero-off-axis configuration is suitable for a wide array of spectral sensing and measurement tasks.
• This advancement represents a significant step forward in high-resolution optical spectroscopy.