Improvement of miniature grating spectrometers

摘要

The trade-off between resolution and signal to noise ratio is a shackle to develop high performance miniature grating spectrometers. Concentrating on breaking this shackle, freeform optics and super-resolution restoration method for miniature grating spectrometers are proposed in this paper. Substituting a varying sagittal surface for a toroidal one, not only aberrations along dispersive direction can be reduced, but also aberrations perpendicular to dispersive direction can be reduced in a broad spectral range. This means both resolution and throughput would be multiplied. To reduce the remnant imperfection of system, subpixel-deconvolution process may be supplemented. By subpixel reconstruction, under-sampling due to finite pixel size of array detector would be got rid of. By deconvolution, blurring duo to slit and other system imperfection would be eliminated. Consequently, resolution and throughput would be further increased.