Toshiba today announced the development of an imaging technique that can simultaneously acquire a color image and a depth map from a single image taken by a monocular camera. This technique achieves high-precision distance/range detection, comparable to that of a stereo camera, through the combination of a lens device and image processing. Various methods for measuring the distance to the object have been proposed, such as stereo cameras, infrared distance sensors, ultrasonic distance sensors, millimeter wave radar, LiDAR, SfM technologyand others. Conventional distance sensors have a variety of advantages and disadvantages. Obtaining a high degree of accuracy in a compact low-cost package is difficult.Toshiba’s proprietary imaging technique uses a combination of color filters and imaging processing to obtain both a color image and high-precision a depth map from a single monocular camera image.
By attaching a proprietary color aperture filter consisting of blue and yellow filters to the lens aperture, a combination of blur and color shift occurs, and this combination depends on the distance to the object. Distance to the object is detected for each pixel through image analysis from the blur and color deviation obtained within a single photographic image. Deterioration in the quality of the captured image is also suppressed, because this color filter allows transmission of green light, which has a higher contribution ratio to overall image brightness. With this new technology, it is now possible to construct an inexpensive image sensor using this method as it consists solely of a lens device and image processing.