1" camera in Xiaomi 12S Ultra: what does it mean?

Xiaomi recently unveiled its flagship camera phone, the 12S Ultra, which became the fifth smartphone with a 1" camera (after Panasonic

DMC-CM1, Sharp Aquos R6, Sony Xperia PRO-I and Sharp Aquos R7).And many, seeing the phrase "inch camera", for some reason decided that Xiaomi fit a 25.4 mm matrix inside the smartphone.But, of course, this is not the case – and today we will arrange a small educational program about what optical size isAfter all, before, seeing in the characteristics a strange abracadabra like "1/1.73", people preferred to scroll further, but now this is one of the important characteristics of the camera, and you need to understand what it means.

Let's start with the fact that the optical size is really the diagonal of the sensor (more precisely, its active area, because the sensor still has "frames" - but they are not counted).More precisely, not quite in inches – Vidicon inches are used for this.One Vidicon inch is equal to 17.3 mm, which is not very much like an inch, you will agree.However, the Vidicon inch, like the regular one, is denoted by a quotation mark-paw ".And this is not a recent invention of marketers to make cameras seem bigger, but a vestigeHistory.



Vidicon

Vidicon is a very ancient variety.camcorder, which was actively used on television in the last century, until digital camcorders appeared. And even now, vidicons are still sometimes used, for example, for high-speed video shooting - but very rarely. The vidicon was a tube inside which an image was formed. Due to the design features, the walls of the tube were quite thick, so a 1-inch (25.4 mm) vidicon made it possible to use a photoconductive target (in other words, a sensor) with a diagonal of only 17.3 mm. Such vidicons were called inch (which is logical), and the diagonal of their sensor was called the vidicon inch.

Photographers had their own system for measuring sizessensors based on the width of the film, but in the world of digital photography it has been almost completely supplanted by the measurement of optical size in Vidicon inches. As a result, almost all manufacturers indicate the optical size of the camera in this strange unit. So Xiaomi is completely honest when it calls the 17.3mm sensor of the Xiaomi 12S Ultra “1″”.

By the way, what does gobbledygook mean?"1/1.73″" – this is the optical size of the Samsung GW1 or Sony IMX686. This literally means "one divided by 1.73 Vidicon inch." That is (17.3/1.73) mm, or 10 mm. For comparison, 1/2.76″ = 17.3/2.76 mm = 6.27 mm (Samsung JN1), and 1/1.31″ = 17.3/1.31 mm = 13.2 mm (Samsung GN1). Well, now you know what to do with it. And you can look at the Xiaomi 12S Ultra camera live and with a ruler in the JerryRigEverything video:

    © Oleg Lazarev.