spherical aberration
- noun
- /ˈsfɛrɪkəl ˌæbəˈreɪʃən/
- Specialized
- To do this, however, it is not sufficient to grind the mirror into a concave shape that is simply a section of a sphere; light that collects across the face of such a simple curve does not all come to the same focus, hence the term "spherical aberration."
- spherical aberration in the telescope
Examples
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The "fog" around the central knots was caused by the spherical aberration error of HST's primary mirror.
Academic text (1990) -
It is a well-known and common problem in making mirrors that telescope makers call spherical aberration.
Academic text (1990) -
How does spherical aberration arise?
Academic text (1990) -
They may have considerable spherical aberration.
Academic text (1994) -
First of all, there are the phenomena of chromatic and spherical aberration.
Academic text (2000) -
The Hubble's spherical aberration spread light out into a fuzzy halo four arc seconds across.
Academic text (1994) -
Lenses that are poorly corrected for spherical aberration will show one kind of disc for out-of-focus points in front of the plane of focus, and a different kind for points behind.
Blog text (18) -
Depending on how a lens is corrected for spherical aberration, the disc may be uniformly illuminated, brighter near the edge, or brighter near the center.
Blog text (18) -
This minuscule error, too small to have been detected in a telescope used from the ground, meant that only a small fraction, about 15%, of the light gathered by the HST was properly focused to a sharp point, a problem called spherical aberration.
Academic text (1994) -
The telescope produced a blurry image due to spherical aberration, which occurs when light rays are focused at different points.
Synonyms
A fault in a lens or mirror that makes images look wrong
A fault in a lens or mirror that makes images look unclear
How Focused
Surface Forms
Morphology
The phrase is a straightforward modifier + noun composition: 'spherical' (sphere-shaped) + 'aberration' (distortion/deviation), so the meaning is an aberration caused by spherical surfaces. A B1 learner who knows both constituents can infer it refers to distortion related to sphere-shaped lenses or mirrors, even if they lack detailed optical knowledge.
Etymology
Spherical aberration uses spherical to show the lens is round and aberration to mean a fault. A round lens bends light from the centre and the edges to different places, so the image becomes 'blurred', which is why the term means a lens problem that makes pictures unclear.