Image sensor and driving method thereof

A driving method of an image sensor, the method comprising:

• receiving, by an image sensor including an active pixel and a dummy pixel, incident light for a first frame;
• generating, by the active pixel, an active signal based on the incident light;
• generating an image output signal based on the active signal;
• determining whether to set an ambient light subtraction mode, with respect to a next frame subsequent to the first frame, based on a dummy signal generated by a dummy pixel,
• wherein the ambient light subtraction mode removes noise caused by ambient light of the incident light;
• and
• driving the image sensor according to whether the ambient light subtraction mode has been set.

A sensor system, comprising:

• a light source;
• and
• an image sensor configured to receive incident light including light output from the light source and ambient light,
• wherein the image sensor includes:
• an active pixel configured to generate an active signal based on the incident light;
• and
• a dummy pixel configured to generate a dummy signal based on the incident light,
• wherein the image sensor is further configured to generate an image output signal based on the active signal, and determine whether to set an ambient light subtraction mode in which noise generated by the ambient light is removed from the image output signal, and
• generate a light source control signal that controls the light source, based on whether the ambient light subtraction mode has been set.