Endoscope apparatus and measurement method

An endoscope apparatus which is capable of performing measurement of a subject using a phase-shift method, the endoscope apparatus comprising:

• a main body;
• an insertion portion which is connected to the main body;
• and
• a plurality of pattern projection units, each of the plurality of pattern projection units comprising:
• a pattern window which is provided in a distal end of the insertion portion;
• and
• a pattern portion which has a line pattern in which a plurality of lines are periodically disposed with a predetermined period, the lines being parallel to each other, wherein:
• the pattern portions of the plurality of pattern projection units are disposed such that the line patterns of the pattern portions are shifted from each other by 1/n of the predetermined period of the line pattern, where the number of the plurality of pattern projection units assumed to be n (n≧3);
• and
• a virtual line on the distal end parallel to the line of the pattern portion intersects each of the pattern windows.

A measuring method of a subject using a phase-shifting method based on images obtained by sequentially projecting first, second, and third patterns on the subject, the first, second, and third patterns having a line pattern in which a plurality of lines parallel to each other are periodically disposed with a predetermined period and being disposed such that phases of the patterns are shifted from each other by a predetermined amount, the method comprising:

• a first step of emitting light from a first light source to the subject via the first pattern and imaging a first subject image on which the first pattern is projected;
• a second step of emitting light from a second light source different from the first light source to the subject via the second pattern and imaging a second subject image on which the second pattern is projected;
• and
• a third step of emitting light from a third light source different from the first and second light sources to the subject via the third pattern and imaging a third subject image on which the third pattern is projected.