Definition

1. Noun:
   • A measuring instrument for measuring the curvature of a surface: A spherometer is a precise device used to determine the radius of curvature of a spherical surface, such as a lens or a mirror.

Usage

• The spherometer is used by placing its three outer legs on the surface and then using a central micrometer screw to measure the sagitta (the depth of the curve).
• It is a standard tool in optics and lens-making workshops for quality control.

Examples

Advanced Usage

• "To take a spherometer reading": The act of using the instrument to obtain a measurement.
  • After grinding the glass, the technician took a spherometer reading to check the progress.

Variants and Related Words

• Spherometry (n): The process or technique of measuring curvature with a spherometer.

Synonyms

• Curvature gauge: A general term for an instrument that measures curvature.
• Lens measure: A similar device specifically associated with measuring lenses.

Notes

• The spherometer is a specialized scientific instrument. Its name is derived from "sphere" and "-meter" (measuring device).

Noun

1. a measuring instrument for measuring the curvature of a surface