What is a positive lens

These lenses are commonly used to achieve tighter beam focusing when paired with another positive lens.If a symmetrical lens were thought of as being a slice of a sphere, then there would be a line passing through the centre of the sphere and attaching to the mirror in the exact centre of the lens.To me, it is the orientation that looks for opportunity and possibility in situations and people, where most others only see adversity, crisis and failure.In other words, if the image is on the far side of the lens as the object, the image distance is positive and the image is real.It has convex surfaces and it has a measureable focal length where it produces an inverted image of a distant object.A positive lens is also called a magnifying lens.

Single diverging lenses only create virtual images, so the fact that a real (inverted) image exists here means this lens must be converging.We recall from lenses and ray tracing that the focal length of a lens is positive for converging lenses and negative for diverging lenses.Its center thickness is bigger than the edge thickness.These ideas are summarized in the figure above and table below.