Thin Lens Equation

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• d_o = 2 m (Object distance)
• d_i = 3 m (Image distance)

Result: f = 1.2 m

Other optics formulas with the same quantities

• Mirror Equation (Reflection) shares Focal length, Object distance, Image distance
• Mirror Magnification (Reflection) shares Image distance, Object distance
• Lens Power (Lenses) shares Focal length
• Focal Length and Radius (Reflection) shares Focal length
• F-Number (f-stop) (Optical Instruments) shares Focal length
• Depth of Field (Optical Instruments) shares Focal length

Where this formula is listed

• Optics formulas, under Lenses, alongside Combined Lens Power.
• In the optics list it comes after Apparent Depth and before Lensmaker's Equation.
• Optics formula sheet, one of 34 formulas printed with symbol keys and SI units.
• The full formula index, grouped by category and topic.