Patent ID: 7465271

Claim:
A capsule endoscope, comprising: a capsule having a substantially cylindrical shape with closed ends, the capsule having a transparent part provided at least at one axial position of the capsule, and the transparent part extending around a circumference of the capsule; an omnidirectional objective optical system positioned substantially coaxial with a central axis of the capsule and configured to receive light reflected by objects positioned around the circumference of the capsule through the transparent part, and the omnidirectional objective optical system being configured to focus an image of the objects on a single image plane which is substantially orthogonal to the central axis of the capsule; an image pickup device which picks up the image focused by the omnidirectional objective optical system and converts the image into an image signal; a plurality of light emitting elements positioned at even angular intervals within the transparent part of the capsule, the plurality of light emitting elements being configured to illuminate substantially all of an image pickup range shot by the omnidirectional objective optical system and the image pickup device, wherein each of the plurality of light emitting elements is positioned so that a central axis of the illuminating light emitted from the plurality of light emitting elements is orthogonal to an optical axis of the omnidirectional objective optical system, and wherein each of the plurality of light emitting elements is positioned so that a central axis of the illuminating light emitted from the plurality of light emitting elements is in a tangential direction of a virtual circle which is coaxial with the omnidirectional objective optical system; a transmitter which wirelessly transmits the image signal outputted by the image pickup device; and an electric power supply which supplies driving currents to the image pickup device, the plurality of light emitting elements and the transmitter.