Definition

1. Noun:
   • A lens made of optical crown glass: A "crown lens" is a lens manufactured from a specific type of optical glass known as crown glass, which has particular properties like low dispersion, making it suitable for optical instruments.

Usage

• The term "crown lens" is a technical term used primarily in optics, photography, and lens manufacturing. It specifies the material composition of the lens.

Examples

• Noun:
  • The microscope's objective uses a high-quality crown lens for minimal chromatic aberration.
  • Optical designers often pair a crown lens with a flint lens to create an achromatic doublet.

Advanced Usage

• In compound lens systems: A "crown lens" is frequently combined with a "flint lens" (made from flint glass) in an achromatic doublet to correct for chromatic aberration, where different colors of light focus at different points.

Variants and Related Words

• Crown glass (n): The type of optical glass from which a crown lens is made. It is characterized by low refractive index and low dispersion.
• Flint lens (n): A lens made from flint glass, often used in combination with a crown lens.

Synonyms

• Optical crown lens: A more explicit synonym emphasizing the optical quality and material.
• Low-dispersion lens: A descriptive synonym highlighting a key property of crown glass.

Related Terms

• Achromatic lens (n): A lens, typically a doublet combining a crown and a flint element, designed to limit chromatic aberration.
• Dispersion (n): In optics, the phenomenon where different wavelengths (colors) of light are refracted by different amounts, which crown glass helps to minimize.

Noun

1. a lens made of optical crown glass