What's the different between aperture and diaphragm?
They both have the same meaning "(相机)光圈"，isn't it?
So, What's the different between aperture and diaphragm?

As usual, which word will you be used to express this meaning"光圈"?

Question

What's the different between aperture and diaphragm?
They both have the same meaning "(相机)光圈"，isn't it?
So, What's the different between aperture and diaphragm?

As usual, which word will you be used to express this meaning"光圈"?

Answer

I assume this is a photography question, about cameras.
Briefly, the aperture is a part of the diaphragm.
The diaphragm is an opaque mechanism in a camera lens, whose function is to regulate the amount of light coming in.  The diaphragm contains an adjustable aperture (a hole whose size can be changed) which allows more or less light to come into the camera.