Definition

Adjective: 1. Free from spherical aberration: In optics, describes a lens or mirror that has been corrected so that it brings light rays from a single point to a single focal point, producing a clear image without this specific type of distortion.

Usage

The word "aplanatic" is a technical term used almost exclusively in the fields of optics, astronomy, and microscopy. It describes the quality of an optical system or component. - It is typically used attributively before a noun (e.g., an aplanatic lens). - It can also be used predicatively (e.g., This mirror is aplanatic).

Examples

• The high-end microscope uses an aplanatic objective to ensure a perfectly sharp image across the entire field of view.
• To achieve high-resolution astrophotography, the telescope must be aplanatic.
• The design of this condenser is aplanatic, correcting for spherical aberration.

Advanced Usage

• Aplanatic condition / point: Refers to the specific design condition or focal point where a lens or mirror is free from spherical aberration.
  • The light source was placed at the aplanatic point of the lens.

Variants and Related Words

• Aplanatism (noun): The state or condition of being free from spherical aberration.
  • The aplanatism of the system is critical for this experiment.

Synonyms

• Corrected (for spherical aberration): A more general descriptive phrase.
• Stigmatic: In precise optical contexts, this can be a near-synonym, meaning an optical system that images a point source as a point.

Antonyms

• Aberrated: Exhibiting optical aberrations.
• Uncorrected: Not corrected for optical flaws like spherical aberration.

Adjective

1. free from or corrected for spherical aberration
   • an aplanatic mirror