Distance detective small camera module

Our new type of camera module is small and thin, and is able to detect the distances of objects as well as their images. The module comprises a four-lens array, one imaging sensor and optical filters. The imaging sensor is divided into four areas, two of which are covered with green filters and the other two with infiared filters. A prototype was fabricated with a focal length of 2.63 mm and a baseline length of 2.59 mm. The two images with the same optical filters have parallax, so the distances of objects can be calculated by comparing the two images. We use infrared images illuminated with infrared LEDs at night, and green images during the daytime. After calibrating the images, we achieved a distance-detection accuracy of within ±2.5% at 1 m in spite of the camera's small baseline length. Consequently, our new distance detection camera module is small and thin, and generates a depth-image of an object as well as its image. Our camera module is thus applicable to vehicles, security systems and three-dimensional imaging.