Intelligent mobile phone In the era, the photo taking effect of mobile phones has become more and more similar to that of ordinary card machines. We often see photos taken by mobile phones in some mobile phone evaluation articles Sharpness contrast. Sharpness, sometimes called "sharpness", is an indicator reflecting the sharpness of the image plane and the sharpness of the image edge. The sharpness of photos taken by mobile phone cameras varies with their sensitivity.
Obviously, the photo sharpness of Canon 500D is better.
Photos taken by iPhone 5 are sharper
Canon has better sharpness
So what determines these subtle differences? The word sensitivity may be unfamiliar to everyone, and the difference in photo sharpness is the difference in the sensitivity of each mobile phone camera. Sensitivity refers to the ability to capture target details under a given scene illumination. It matches the sensitivity with the scene brightness according to the shutter speed, which is the most basic aspect of image imaging in any photographic system.
Semiconductor image sensors collect information by relying on their photoelectric effect, and convert light into electronic energy with virtual ability. The sensitivity of the image sensor depends on the size of the light sensing area (the larger the pixel, the more photons can be captured) and the photoelectric conversion efficiency (i.e. QE). QE is affected by both pixel design process and wavelength. The optical insensitive structure on the pixel can absorb light (absorption loss), and the semiconductor itself affects a certain wavelength (reflection loss). At the same time, long or short wavelengths may be completely lost when passing through the sensitive layer of the pixel, without producing electrons (transmission loss). Sensitivity needs to generate more charge through photoelectric effect. In order to obtain sensitivity, image sensor must be able to manage and calculate the generated signal without loss or noise.
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