Opject Versus Image Distance in Optics

Image from Unsplash 

The lens equation is given by:

1/f = 1/do + 1/di

where f is the focal length of the lens, do is the object distance (distance between the object and the lens), and di is the image distance (distance between the image and the lens).

The Object Distance:

The object distance is the distance between the actual object that is being observed and the lens. It is typically measured along the principal axis of the lens.

The Image Distance:

The image Distance is the distance between the image formed by the lens and the lens itself. It is also measured along the principal axis of the lens.

Relation between these distances and lens equation: 

• The lens equation shows that the object distance and image distance are inversely proportional to each other. 
  
• This means that if the object distance increases, the image distance decreases, and vice versa. 
  
• This relationship holds true as long as the lens is not moved or changed.
  

In practical terms, the object distance determines the size of the image formed by the lens. A larger object distance will result in a smaller image, while a smaller object distance will result in a larger image.

Understanding the relationship between object distance and image distance is crucial in many applications, such as in photography, microscopy, and telescope design, where the size and distance of the object and image need to be carefully controlled and adjusted.