The 1/5" sensor size indicates the physical dimension of the image chip in a camera. The fractional notation, for example 1/5 inch, is a historical designation and does not directly correspond to the sensor's diagonal. It originates from the outer diameter of old image pickup tubes, while the actual area for image recording was smaller. A 1/5-inch sensor is among the very small ones. A smaller sensor area means that less light falls on it. This can manifest as a higher level of digital noise, which is an image defect resembling grain, especially when shooting in poor lighting conditions. At the same time, this dimension leads to a large depth of field, where most of the scene from foreground to background is in focus. This makes it more difficult to achieve the blurred background effect, known as "bokeh". This type of sensor is typically found in older mobile phones, webcams, or basic digital devices.