Optical imaging method and optical imaging apparatus using optical coherence tomography

An optical imaging method for forming a tomographic image of an object by processing an interference spectrum based on an interference light that is obtained by combining a signal light passing through said object and a reference light, characterized in that the method comprises:

• a scanning step to scan each of a plurality of A-lines of the object with the signal light while alternately changing the phase difference between the signal light and the reference light to two preset phase differences;
• a detection step to detect an interference light of said signal light passing through the A-line and said reference light;
• and
• an imaging step to generate a complex interference spectrum based on the detection results of said interference lights corresponding to said plurality of A-lines sequentially obtained in said detection step according to said scanning, and form, based on the complex interference spectrum, the tomographic image along the arrangement of the plurality of A-lines in which a complex conjugate artifact is substantially removed,
• wherein the process of generating said complex interference spectrum comprises:
• a process of obtaining a first interference spectrum by applying a low pass filter to the interference spectrum based on the detection results of said interference light, and obtaining a real part by dividing said first interference spectrum by the cosine of said phase difference;
• a process of obtaining a second interference spectrum by multiplying the interference spectrum based on said detection results by −(−1)n and applying a low pass filter on this product, and obtaining an imaginary part by dividing said second interference spectrum by the sine of said phase difference;
• and
• a process of generating said complex interference spectrum by adding said real part and a product obtained by multiplying said imaginary part by an imaginary unit.