Why are all cameras vertical and wide? Why is it designed like this?

Question 1. Why are the lenses round?

This is related to the way the lens glass is polished. In order to ensure the uniformity and uniformity of the spherical and aspherical surfaces of the lens, Symmetry, generally when polishing, the lens and abrasive are constantly rotating, so it is natural to make a round shape. It is also natural for a round lens to be round.

In addition, the lenses of some lenses rotate during focusing and zooming operations, which is also a reason for the round shape.

Question 2. Why do photos and videos always have rectangular screens?< /p>

Early films were square, because if they were square, there would be no wasted area between two adjacent films, and if they were round, imagine two circles.

Today's digital CCD and CMOS image sensors can be made into circular shapes, and there is no technical problem. However, the computers, monitors, televisions, digital photo frames, etc. that we all use to view photos all have square screens, so in order not to Wasteful, the sensor is naturally made into a square shape.

Let me ask a question

What is the shape of the image of a round lens?

The answer is also the same Circular, the imaging area of ??the lens is larger than the CMOS area, completely covering the CMOS, so the digital camera is just a part of the lens imaging. In fact, many high-end lenses, such as 70-200mmF2.8, have a shape at the end of the lens It becomes a square shape, which can block unnecessary light (the part projected outside the CMOS) and reduce the impact of excess light.