Sony FCB camera block
First, the introduction of optical lens aperture
What is an aperture? It may be that many people touch the camera every day but still do not know much about it. Simply put, an Aperture is a device used to control the amount of light passing through the lens and entering the light-sensitive surface of the fuselage. The English name is Aperture. The aperture plays a pivotal role in the lens. As the core parameter controlling the exposure of a photo, its size determines how much light enters the photoreceptor through the lens. We usually use the F-number to express aperture size.
Aperture F = focal length of the lens/diameter of the lens aperture. Standard aperture values from large to small are :F1, F1.4, F2, F2.8, F4, F5.6, F8, F11, F16, F22, F32, F44 and F64. The smaller the aperture value under the same focal length, the larger the effective light aperture of the lens, the more light in unit time, for example, when the aperture is adjusted from F4.0 to F2.8, the amount of light in is doubled. For industrial camera zoom lenses, the aperture F value is usually between F1-F8. SONY FCB-EV9500M aperture F value is F1.6 to F4.8, the following Xuan Zhan technology will take you to see a variety of different aperture types.
SONY FCB-EV9500M
Two, different types of aperture
Although there are a variety of image products on the market, from digital SLR cameras, digital side sleeves, cameras, cameras, monitors, to our industrial cameras, but according to the different internal structure and different market positioning, the common lens aperture is only divided into three categories: fixed aperture, cat eye aperture and iris aperture.
1. Fixed aperture
As the name implies, the lens with a fixed aperture cannot adjust the size of its aperture. This aperture is usually used on low-end devices, such as mobile phone lenses, cameras and monitors, which require less optical performance.
2, cat eye aperture
Cat’s eye aperture is also a common aperture structure, because of its shape like a cat’s eye named. This aperture consists of a sheet of metal with an oval or diamond-shaped hole in the center divided in half and two sheets of metal with a semi-oval or diamond-shaped hole lined up. The cat-eye aperture is widely used in entry-level consumer cameras because it is cheap to build and can be resizable at will.
3, iris type aperture
Iris type aperture is composed of a number of overlapping arc-shaped aperture blades, the number of aperture blades can be up to 18, and the more the number of blades iris type aperture closer to the circle. Most consumer camera lenses and almost all DSLR camera lenses now use this aperture structure because the clutch of the blades can change the size of the central circular aperture and the multi-blade design can provide a closer to circular light transmission aperture. Now there are more and more industrial cameras using this structure of aperture, SONY FCB-EV9500M is the use of seven petals iris aperture.
FCB-EV9500M 7-blade aperture
3. What are the advantages of SONY FCB-EV9500M’s iris aperture with 7 petals
The iris aperture used by SONY FCB-EV9500M lens is composed of a total of 7 petals, which makes the glare/halo will be relatively better round. When the aperture is fully open, the light pass aperture of the lens is bright and wide, which makes the amount of light pass per unit time more, thus greatly improving the image quality.
FCB-EV9500M 7-blade structure aperture effect comparison