PROBLEM TO BE SOLVED: To provide a cylinder inner surface observation device that can photograph an inner surface of a cylinder in a higher speed even if the cylinder is small in diameter.;SOLUTION: A cylinder inner surface observation device comprises: a light ray information acquisition device 100 that creates light ray information on an inner surface of a cylinder irradiated with illumination light; and a computation processing device that performs prescribed image processing to the created light ray information. The light ray information acquisition device 100 has: an illumination light source 101 that irradiates the illumination light; a light field camera 103 that acquires the light ray information on an inner surface of a cylinder S; and a light ray acquisition optical system 105 that has at least a conical prism or conical mirror 121, and guides an image of the illumination light in the inner surface of the cylinder to the light field camera. The computation processing device is configured to: convert light ray information in an orthogonal coordinate system into a polar coordinate system with a radial direction of the cylinder as a motion radial direction; change a focus position in an axial direction of the cylinder and in a peripheral direction thereof, using the light ray information in the polar coordinate system; and execute image reconstruction processing.;SELECTED DRAWING: Figure 2A;COPYRIGHT: (C)2018,JPO&INPIT
展开▼
