- #1
Kuzon
- 42
- 5
Why isn't 1/f=1/do+1/di just the mathematical equivalent to f=do+di? Can't you raise all terms in the equation to the power of negative 1 to get the latter equation? The maths of reciprocals is confusing me lol.
Sahil Kukreja said:That is not the lens eqn.
The lens equation is :- 1/f = 1/v - 1/u
pixel said:Kuzon has written a perfectly acceptable version of the lens equation, one that is commonly used.
Kuzon: raising to a power does not follow a distributive law as does multiplication. So we have a(b + c) = ab + ac but (b + c)2 ≠ b2 + c2.
Sahil Kukreja said:Sorry, I did not know that version of lens equation; as in our country the lens equation version used is different.
The thin lens equation is a mathematical formula that relates the distance of an object from a lens, the distance of the image from the lens, and the focal length of the lens. It is given by 1/o + 1/i = 1/f, where o is the object distance, i is the image distance, and f is the focal length of the lens.
The thin lens equation is derived from the basic principles of geometric optics, specifically the law of refraction and the principle of similar triangles. By applying these principles to a thin lens, the equation can be derived to describe the relationship between object and image distances.
The thin lens equation assumes that the lens is thin, meaning its thickness is negligible compared to its focal length. Additionally, it assumes that the lens is made of a homogeneous material and that light passes through the lens without being absorbed or scattered. It also only applies to thin lenses, not thick lenses or other optical systems.
The thin lens equation is used in a variety of optical systems, such as cameras, eyeglasses, and microscopes. It can be used to calculate the location and size of an image formed by a lens, as well as to determine the necessary focal length for a desired image distance. It is also used in the design and analysis of optical instruments.
One common misconception is that the thin lens equation only applies to convex lenses. In reality, it applies to both convex and concave lenses. Another misconception is that the equation can only be used for objects placed at a distance from the lens. It can actually be used for objects at any distance, as long as the other two variables are known.