Endoscope with flexible Tip and Chip-on-the-Tip Camera

Abstract

Construction of laparoscopes has remained unchanged for some decades. A series of rod lenses transports the image through a long rigid tube. A camera mounted outside the patient’s body captures the image, which is displayed on a video screen. A new quality in endoscopic imaging arose with the introduction of flexible fiber-optic endoscopes, which permit vast deflection angles of the distal end. However, the resulting image very often seems pixelated and exhibits an insufficient resolution. Until now, high-definition camera images are only available when using straight scopes which may have angled tips to effectively look around corners. Still, the physician only obtains a limited view of the surgical site. This situation is improved by rotating the straight endoscope shaft around a pivot point, given by e. g. an incision in the abdominal wall of the patient. Because the endoscope is controlled mainly by an assistant, a good coordination between physician and assistant is mandatory for an effective image control. We in contrast developed a new type of endoscope with a flexible endoscope tip which allows a change of angle of view without rotating the horizon of the image. The movement of the tip, and thus the change of angle of view in any desired direction, is generated by motorized spindles. Fixing the shaft of the endoscope with a holder facilitates automatically and repeatedly finding defined areas with high accuracy. The flexible tip contains an optical system as well as a digital image sensor with miniaturized linear motors moving the optical lenses both for focusing and zooming. Image focusing may be regulated by use of a simple knob. Image contrast may also be evaluated by a fast microprocessor which feeds the motor’s power supply to adjust the focal lens to the position corresponding to the sharpest image.