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Image Distance Calculator Convex Lens Angle

Convex Lens Equation:

\[ d_i = \frac{f \times d_o}{d_o - f} \]

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1. What is the Convex Lens Equation?

The convex lens equation relates the focal length (f) of a lens to the object distance (do) and image distance (di). It's fundamental in geometric optics for determining where an image will form.

2. How Does the Calculator Work?

The calculator uses the convex lens equation:

\[ d_i = \frac{f \times d_o}{d_o - f} \]

Where:

Explanation: The equation shows that when the object distance approaches the focal length, the image distance becomes very large (approaching infinity).

3. Importance of Image Distance Calculation

Details: Calculating image distance is crucial for lens design, photography, microscopy, and any optical system where precise image formation is needed.

4. Using the Calculator

Tips: Enter focal length and object distance in meters. Both values must be positive, and object distance cannot equal focal length (which would make the denominator zero).

5. Frequently Asked Questions (FAQ)

Q1: What happens when do = f?
A: The denominator becomes zero, meaning no real image forms (the image is at infinity).

Q2: What does a negative di mean?
A: A negative image distance indicates a virtual image formed on the same side as the object.

Q3: How does this relate to magnification?
A: Magnification (m) can be calculated as m = -di/do once you have the image distance.

Q4: Is this only for thin lenses?
A: Yes, this equation applies specifically to thin lenses in the paraxial approximation.

Q5: What about concave lenses?
A: For concave lenses, the focal length is negative, and the equation works similarly but produces different results.

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