METHOD OF MEASURING A DISTANCE AND THREE-DIMENSIONAL IMAGE SENSOR PERFORMING THE SAME

摘要

PURPOSE: A distance measuring method and a 3D image sensor performing the same are provided to improve the reliability of correlated double sampling by preparing a temporary storage area on a distance pixel and efficiently removing a noise. CONSTITUTION: A light sensing device emits modulated transmitting light to a subject(S100). The light sensing device stores a photocharge in a temporary storage area of a distance pixel(S200). The light sensing device supplies a reset voltage to a floating diffusion area of the distance pixel(S300). The light sensing device electrically connects the temporary storage area with the floating diffusion area after detecting a noise voltage(S400). The light sensing device detects a demodulation voltage(S500). The light sensing device determines an effective voltage from a difference between the noise voltage and the demodulation voltage(S600). [Reference numerals] (AA) Start; (BB) End; (S100) Emitting modulated transmitting light to a subject; (S200) Storing a photocharge in a temporary storage area by responding a demodulated signal; (S300) Detecting a noise voltage after applying a reset voltage to a floating diffusion area; (S400) Electrically connecting the temporary storage area and the floating diffusion area after detecting the noise voltage; (S500) Detecting the demodulated signal after electrically connecting the temporary storage area and the floating diffusion area; (S600) Determining an effective voltage from a difference between the noise voltage and the demodulation voltage