Xiaomi 12S Ultra was officially released on July 4th this year. One-inch outsole Sony IMX989 sensor plus Leica benefit became the main promotional selling point of this new device. Some people are also curious about this one. Is the inch sensor a real one-inch, so recently JerryRigEverything disassembled and measured this one-inch outsole processor.
JerryRigEverything used two one-inch pieces of paper to compare this one-inch sensor and found that the size of the sensor was a little worse, and then used a digital vernier caliper to find that it was about 0.54 inches (13.7mm) long and about 0.66 inches diagonally ( 16.7mm), which is a far cry from the advertised one inch.
But in fact, this one inch is somewhat different from what we understand. One inch should be 25.4mm when converted to metric units, but the one-inch sensor is not 25.4mm in terms of length, width, height, or diagonal. The size of the one-inch bottom is 13.2×8.8mm, and the diagonal length is 15.9mm, which is 0.63 inches.
It can’t be said that all camera manufacturers and mobile phone manufacturers are false propaganda. The reason for this is that in the 1950s and 1960s when electronic imaging technology was just emerging, the photosensitive electronic components used vacuum tubes.
The CCD and CMOS sensors on digital cameras must not exist at that time, and the vacuum tube has a glass cover on the surface. When calculating the outer diameter, the glass cover should be included, but the glass cover itself cannot be used. Therefore, the actual imaging size of the photosensitive electronic components made is smaller than the outer diameter of the vacuum tube by one inch, and the diagonal of the actual imaging area is only about 16mm, so this has become a convention or a standard.
The inch sensor is also according to this statement, one inch = 16mm, this is a problem that has existed for a long time, and any company that makes sensors have not changed it, so we have to get used to it: sometimes an inch is not equal to real of an inch.
Xiaomi is not the first mobile phone manufacturer to apply a one-inch sensor. In front of him are the Sharp Aquos R6 and Sony Xperia PRO-I, both of which are released in 2021. The focal length of Sharp’s main camera is 35mm, the equivalent conversion is only 19mm.
This focal length is closer to the ultra-wide-angle lens (0.6-0.8 times zoom) that we are familiar with every day, which does not conform to our daily shooting habits. If you want to convert it into a common 24mm focal length, you can only This is achieved it by cropping the area used by the sensor. The Sony one inch is also cropped, and only 1/1.33 inch is really used.