The present disclosure relates to an endoscope and an endoscope apparatus.
Observing (photographing) an affected part or performing various treatments for an affected part by using an endoscope has become widespread, from the viewpoint of minimally invasive medical treatment which reduces the physical burden on a patient (a person under measurement) as much as possible. In order to implement such minimally invasive medical treatment, a thickness (diameter) of a lens barrel of the endoscope inserted within the body cavity of a person under measurement is generally sought after which is equal to or less than approximately several mm.
On the other hand, three-dimensional endoscopes (3D endoscopes) which can display photographed positions as three-dimensional images (3D images) have become widespread in recent years. In 3D endoscopes, 3D images are generated based on pixel signals (image signals) acquired by each of a pair of image sensors included in the distal end of the lens barrel of the endoscope. Since various treatments can be performed by using a 3D endoscope while referring to 3D images close to what is actually seen by the human eyes, it becomes possible for a medical practitioner (a user) to operate the endoscope more intuitively.
Here, in a 3D endoscope, in order to secure a sufficient photographing range for treating an affected part, it is preferable that a prescribed distance is secured as an interval between the pair of image sensors. However, when the pair of image sensors is arranged while securing this prescribed distance in the distal end of the lens barrel of the endoscope, there is the possibility that the diameter of this lens barrel part will increase. Accordingly, technology has been developed in which the image sensors are stored within the lens barrel, while moving up to an affected part, inside the body cavity of the person under measurement, and photography is performed by allowing the image sensors to be projected from within the lens barrel at the time when the affected part is reached.
For example, JP S63-294508A discloses a stereoscopic endoscope apparatus which has a pair of imaging sections projecting in a radial direction of a lens barrel from mutually different positions of the outer surface of the lens barrel. Further, JP H4-500768A discloses an endoscope which has a pair of imaging sections included at mutually different positions on the outer wall of a lens barrel, which project in a radial direction of the lens barrel by eccentrically rotating with respect to the center of the end surface at the distal end of the lens barrel, around a rotation axis parallel to an extension direction of the lens barrel.