Optics
Combined Lens Power
For thin lenses in contact, the total power is the sum of individual powers.
Variables
PtotalD
Total power
P1D
Power of lens 1
P2D
Power of lens 2
Your notes
0/5000
Check value
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- P1 = 2 D (Power of lens 1)
- P2 = 3 D (Power of lens 2)
Result: Ptotal = 5 D
Where this formula is listed
- Optics formulas, under Lenses, alongside Thin Lens Equation, Lensmaker's Equation and Lens Magnification.
- In the optics list it comes after Lens Power and before Double-Slit Interference.
- Optics formula sheet, one of 34 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Combined Lens Power formula?
Combined Lens Power is written P_total = P₁ + P₂. For thin lenses in contact, the total power is the sum of individual powers. It belongs to Optics, under Lenses.
What are the units in P_total = P₁ + P₂?
In SI units, P_total is total power, measured in D; P₁ is power of lens 1, measured in D; P₂ is power of lens 2, measured in D.