The defocus value ( z ) can be used to counteract the spherical aberration to allow for greater phase contrast.
32.
The best of the lenses have low spherical aberration, indicating that their surface profile was optimized to improve image quality.
33.
The latter is dependent on the electron-optical qualities, such as spherical aberrations, and the energy spread of the photoemitted electrons.
34.
If the mirror is made parabolic, to correct the spherical aberration, then it must necessarily suffer from coma and astigmatism.
35.
It is noted for producing a sharp image, with good correction for chromatic and spherical aberration as well as distortion.
36.
The optics of the Hubble were flawed, and Faber and her team helped to diagnose the cause as spherical aberration.
37.
Immediately after its launch, it was found that the main mirror suffered from spherical aberration, severely compromising the telescope's capabilities.
38.
An apochromat is a lens or lens system with even better chromatic aberration correction, combined with improved spherical aberration correction.
39.
Use of an oil immersion lens with the incorrect immersion oil, or without immersion oil altogether, will suffer from spherical aberration.
40.
Aimpoint markets their sights as " parallax free ", but this seems to refer to their off-axis spherical aberration correction system.
