Endoscope and adaptor for endoscope

An endoscope comprising:

• a first concave lens, a first light flux from a first region of a subject being incident on the first-concave lens;
• a second concave lens, a second light flux from a second region of the subject being incident on the second concave lens, the second light flux being in a direction orthogonal to the first light flux, the second region being different from the first region;
• a prism comprising a mirror region, the first light flux and the second light flux each being incident on the prism, the first light flux and the second light flux passing through the prism at an intersecting portion of the prism, the second light flux being reflected by the mirror region after passing through the intersecting portion, the first light flux and the second light flux being emitted from the prism to a predetermined region;
• a light-shield disposed at the predetermined region, the light-shield comprising two holes through which the first light flux and the second light flux pass through, respectively, the light-shield being configured to selectively shield one of the two holes;
• an image sensor comprising an imaging area;
• and
• an imaging lens disposed closer to the image sensor than the light-shield is, the imaging lens being configured to form images of the first light flux passing through the first concave lens and of the second light flux passing through the second concave lens at a common region of the imaging area;
• wherein
• the first concave lens is disposed such that the first light flux from the first concave lens being incident in a direction substantially parallel to the optical axis of the imaging lens and directed toward a center of the image sensor, the first light flux being disposed only on a first side of an optical axis of the imaging lens;
• and
• the second concave lens is disposed so that the second light flux from the second concave lens being incident in a direction substantially orthogonal to the optical axis of the imaging lens and directed toward the center of the image sensor, the second light flux being disposed only on a second side of the optical axis of the imaging lens, the first side and the second side are offset in a direction perpendicular to the optical axis of the imaging lens with the second side being opposite to the first side relative to the optical axis;
• the endoscope further comprising:
• a first decentered lens disposed on the first side of the optical axis of the imaging lens, the first decentered lens being configured to deflect the first light flux such that a part of the first light flux emitted from the prism and passing through a center of one of the two holes reaches a center of an image formed on the image sensor, the part of the first light flux being inclined with respect to the optical axis of the imaging lens;
• and
• a second decentered lens disposed on the second side of the optical axis of the imaging lens, the second decentered lens being configured to deflect the second light flux such that a part of the second light flux emitted from the prism and passing through a center of an other of the two holes reaches the center of the image formed on the image sensor, the part of the second light flux being inclined with respect to the optical axis of the imaging lens;
• wherein the first light flux passes through the first decentered lens, the one of the two holes of the light shield and then is incident on the imaging lens, the second light flux passes through the second decentered lens, the other of the two holes of the light shield and then is incident on the imaging lens.