Downhole Optical Imaging Tools and Methods

摘要

A disclosed downhole optical imaging tool includes a light source and a camera enclosed within a tool body having at least two sidewall windows. A first window transmits light from the light source to a target region in the borehole, while a second window passes reflected light from the target region to the internal camera. The target region is spaced along the borehole away from the second window in a direction opposite the first window. In some embodiments, this configuration is provided by angling the first and second windows with respect to the sidewall, or by shaping the windows to cast and receive light from a “forward” direction. Some tool embodiments include motion and/or orientation sensors that are employed by a processor to combine separately captured images into a panoramic borehole image. It can be employed during drilling operations employing air or a substantially transparent liquid as a drilling fluid.