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Thin Lens Equation:
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The thin lens equation relates the focal length of a lens (f) to the distances of the object (do) and the image (di) from the lens. It's a fundamental equation in geometric optics that applies to both converging and diverging lenses.
The calculator uses the thin lens equation:
Where:
Explanation: The calculator automatically determines which value is missing (f, do, or di) and calculates it based on the other two provided values.
Details: Understanding lens equations is crucial for designing optical systems, eyeglasses, cameras, telescopes, and other imaging devices. It helps predict image formation characteristics.
Tips: Enter any two known values (f, do, or di) in meters, leaving the field you want to calculate empty. The calculator will compute the missing value.
Q1: What's the sign convention for the thin lens equation?
A: For lenses, f is positive for converging lenses and negative for diverging lenses. di is positive for real images (same side as outgoing light) and negative for virtual images.
Q2: What happens when the object is at the focal point?
A: When do = f, the image distance becomes infinite (parallel rays), meaning no image is formed.
Q3: How does this relate to magnification?
A: Magnification (m) can be calculated as m = -di/do. Negative magnification indicates an inverted image.
Q4: What are the limitations of the thin lens equation?
A: It assumes perfect, thin lenses with negligible thickness. Real lenses have thickness and imperfections that may affect results.
Q5: Can this be used for concave mirrors?
A: Yes, the same equation applies to spherical mirrors with appropriate sign conventions.