PHYSICAL QUANTITY
Focal length: formulas and units of measurement
Focal length: symbol F, unit m. Formulas and explanations for Optics.
Fmeter
KEY CONNECTIONS
Formulas
1 / F = 1 / d + 1 / f
F = df / (d + f)
D = 1 / F
NOTATION
Quantities in formulas
- Focal length is the distance from the optical center of the lens to its main focus.
- Object distance - the distance from the lens to the object in question.
- Image distance is the distance from the lens to the resulting image.
- Optical power is the ability of a lens to collect or scatter light.
THEORY
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PRACTICE
Related tasks
DIRECTORY
Other formulas on the topic
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