Patent ID: 7153259

Claim:
A capsule type endoscope comprising: illumination means for illuminating an object; imaging means for imaging the object; and a transparent cover for covering the illumination means and the imaging means, wherein the imaging means includes an objective optical system and an image sensor, and when the objective optical system satisfies Condition (1) described below and a white cylinder with a reflectance of 90%, satisfying Condition (3) described below, is observed, illuminance of an imaging surface of the image sensor satisfies Condition (2) described below, in a state where a longitudinal center axis of the capsule type endoscope coincides with a center axis of the white cylinder with a reflectance of 90%: ω≧50° (1) T 1 ×0.5 ≦T 2 (2) D= 1.2×Φ (3) where ω is a half of a field angle of the objective optical system, T 1 is a maximum illuminance in an area on the imaging surface of the image sensor corresponding to a field region of the objective optical system, T 2 is illuminance at a position on the imaging surface of the image sensor corresponding to a half of a maximum image height of the objective optical system, D is the inside diameter (mm) of the white cylinder, and Φ is the outside diameter (mm) of the capsule type endoscope.