Why not square or rectangular?
Camera lenses are circular in shape. This fact has a lot of reasons behind it. Had the camera lenses been of any other shape such as square, triangular or rectangular, there would be an altogether different perspective to photography. There are a number of scientific reasons behind the circular shape of camera lenses. It has been widely observed that in optics, circular or spherical shapes work well, in comparison to others.
The reasons for such a shape of the lenses vary from manufacturing to lens rotation to a wider perspective. WittyFeed has tried to search for an answer to this question. Read on to find out the explanations. So, no need to bother your shutterbugs as your curiosity has been answered here.
Generally, it is easier to make circular camera lenses. They are cheaper to make and easier to calibrate when different lenses are combined to achieve a particular power and measure. Also to produce macro and telephoto lenses, circular is the preferred shape.
The opening of a diaphragm and the aperture give rise to a circular space, this is the reason a circular lens will produce the best results. The opening of a diaphragm is in a spiral shape, which looks like a circle.
A circular lens has the ability to rotate without occupying any extra space. Spherical lenses provide better and wider perspective for the wide angle lenses. They are easier to adjust.
Rotating either triangular, square or rectangular lens is very difficult. It is more convenient to rotate circular lenses, for the purpose of zoom and focus. The adjustment of zoom and focus is done using rotation only. This is one of the reasons for the acceptance of circular shape.
They help in focusing light at a single point. Adjusting and rotating lens converge the light coming into the camera at a point on the screen or mirror. This is how an image is captured. But, this image is inverted, which is later reinverted for us to view it correctly.
One of the most important features of a lens is its ability to gather light even in the case of dim lighting. The circular shape of a lens makes this easier. In optics, it is essential to use circular shapes for best results.
High quality images are produced if the lens surface is very accurate to provide high precision. Although it is not impossible to produce high quality images through lens of other shapes, the grinding and polishing processes while making a lens are performed to ensure the desired accuracy. This is best achieved in a circular shape.
The shape of a circle is such that it minimises the maximum dimension for a particular area. The larger the optical dimension, the lower is the optical quality. Thus, the light gathering capacity of a lens is largely affected by the governed area.
These are the reasons for using circular camera lenses. Do keep them in mind. So, take out your cameras and head out photographing. Your commitment to photography is truly proven if you have lenses of Canon to give a vision to your passion.