Tetracell: The tech behind Samsung's 108 MP smartphone camera sensor
This new sensor comes after the partnership between Samsung and Xiaomi. The sensor has been termed ISOCELL Bright HMX.
We already have smartphones with 64 MP camera but the next one from Xiaomi will have a 108 MP camera. This new sensor comes after the partnership between Samsung and Xiaomi. The sensor has been termed ISOCELL Bright HMX.
Its resolution is equivalent to a high-end DSLR camera. The mass production of the Samsung ISOCELL Bright HMX image sensor will begin later this month.
The HMX sensor is one of the first mobile sensors with a large size (1/1.33-inch). This bigger size helps in the absorption of more light (as compared to small sensors) and taking better pictures in low-light conditions. This is because the quality of an image is dependent on the image sensor of a camera. An image sensor is a device that detects and processes the light coming through the camera lens.
How does an image sensor work?
When light falls on a camera lens, the image sensor converts it into digital signals. These digital signals are sent to the processor in a camera that converts it into a digital image. Bingo, you have the image you just captured with all these processes happening within seconds.
What is a colour?
White light is a combination of seven colours but only three major colours: red, blue, and green, which can combine to form the rest of the colours.
A colour is something reflected by an object. So, if an object is pink in colour that means its reflecting that particular colour and absorbing others.
An image sensor has to detect these colours.
Quality of an Image:
The structure of an image sensor determines the final quality of a photo.
A high-resolution image has a large number of pixels in it. Pixels are the small blocks that make up an image. So, the more small blocks, the better the image quality. The quest is to increase the number of pixels in an image. How do we do that?
Another aspect of a quality picture is the availability of light.
The size of each individual pixel impacts the light-sensitivity of an image sensor. So, if a pixel is large, the better it is at absorbing light. The more the light, the better the image.
How are we going to get larger and bigger pixels? What is the solution? How do we get good images (both high resolution and well illuminated) in low-lighting conditions?
One way is to install a large image sensor, such as the ones seen in high-end cameras. But since smartphones are a portable device, a large image sensor will make it bulky.
That's where the new Tetracell technology comes in.
What is Tetracell technology?
What if the size of a pixel can be changed with lighting conditions?
The engineers behind Tetracell technology tried to transform the structure of a pixel using an algorithm. The algorithm places pixels with the same colour next to each other in a group of four.
When there is low-light, these pixels become bigger by joining together, providing an illuminated picture. The algorithm combines information and data from each group transforming the smaller pixels into a larger pixel.
When in bright light conditions, the algorithm remaps the pixels into a normal image pattern with a pattern called re-mosaic algorithm to produce a high-resolution image.
Benefits of Tetracell technology and how the image sensor is different as compared to previous ones:
- It improves image quality in both bright and dark lighting conditions.
- It also improves HDR (High Dynamic Range) performance in a high-contrast environment.
- The new image sensor has a large 1/1.33-inch size that helps in absorbing more light in low-lighting conditions.
- The Tetracell technology helps in producing brighter 27Mp images.
- It can record a video at 6K (6016 x 3384) 30-frames-per-second (fps). So, 6K recording on a smartphone.
- The technology helps in reducing the noise in a picture, therefore making it clearer.