# Aperture ratio – Definition & Meaning

Aperture ratio is a term used in photography and optics to describe the ratio of the diameter of the aperture to the focal length of the lens. It is an important concept in understanding how light enters a camera lens and affects the final image.

## Definitions

Aperture ratio is defined as the ratio of the diameter of the aperture to the focal length of the lens. It is also known as the f-number or f-stop. The aperture ratio determines how much light enters the camera lens and affects the depth of field and exposure of the final image.

## Origin

The concept of aperture ratio dates back to the early days of photography when cameras were first invented. It was first described by Joseph Petzval, a Hungarian mathematician and physicist, in the mid-19th century. Petzval’s work on optics laid the foundation for modern photography and his formula for calculating the aperture ratio is still in use today.

## Meaning in different dictionaries

The meaning of aperture ratio is consistent across different dictionaries. It is defined as the ratio of the diameter of the aperture to the focal length of the lens. It is also known as the f-number or f-stop.

## Associations

Aperture ratio is closely associated with depth of field and exposure in photography. A smaller aperture ratio (larger f-number) results in a greater depth of field and a darker exposure, while a larger aperture ratio (smaller f-number) results in a shallower depth of field and a brighter exposure.

## Synonyms

The synonyms of aperture ratio include f-number, f-stop, and relative aperture.

## Antonyms

There are no direct antonyms of aperture ratio, but a larger aperture ratio (smaller f-number) can be contrasted with a smaller aperture ratio (larger f-number).

## The same root words

The root words of aperture ratio are aperture and ratio. Aperture refers to the opening in a camera lens that allows light to enter, while ratio refers to the relationship between two quantities.

## Example Sentences

• A smaller aperture ratio (larger f-number) will result in a greater depth of field.
• The aperture ratio of this lens is f/2.8.
• A larger aperture ratio (smaller f-number) will result in a brighter exposure.
• The aperture ratio determines how much light enters the camera lens.