What is an Aberration?

An aberration is an optical imperfection that causes an optical system to deviate from its ideal performance. In a perfect optical system, all light rays would be focused exactly where intended. In practice, lenses, mirrors, and other optical components introduce small errors that can blur images, distort shapes, or reduce spectral resolution.

Optical aberrations are generally classified into two categories:

• Chromatic aberrations occur because different wavelengths of light are focused at different positions.
• Monochromatic aberrations occur even when only a single wavelength is present and include effects such as spherical aberration, coma, and astigmatism.

In spectroscopy, aberrations can reduce wavelength accuracy, broaden spectral features, and decrease the ability to distinguish closely spaced peaks. Optical designers minimize these effects through careful selection of lenses, mirrors, gratings, and optical layouts.

The StellarNet BLACK-Comet series utilizes a concave grating optical design that helps reduce aberrations, improving spectral resolution, optical throughput, and overall measurement performance.