Under-screen fingerprint sensing device and fingerprint sensing method

An under-screen fingerprint sensing device, adaptable for an electronic equipment with a display device, comprising:

• a fingerprint sensor, disposed under the display device, and the fingerprint sensor having a pixel array, wherein the pixel array has a first color pixel, a second color pixel and a third color pixel, when the fingerprint sensor senses a target object, the first color pixel, the second color pixel and the third color pixel respectively output a first color original value, a second color original value and a third color original value;
• and
• a processor, coupled to the pixel array, wherein the processor performs a flat-filed correction (FFC) on the first color original value, the second color original value and the third color original value respectively to generate a first color correction value, a second color correction value and a third color correction value,
• wherein the processor determines whether the first color correction value, the second color correction value and the third color correction value satisfy a preset condition, so as to determine whether the target object is a real finger,
• wherein the preset condition is that the processor determines whether a first value obtained through dividing the first color correction value by the second color correction value, a second value obtained through dividing the second color correction value by the third color correction value, and a third value obtained through dividing the first color correction value by the third color correction value are greater than a first threshold and less than a second threshold, respectively, to determine whether the target object is the real finger.