Engineers at ifm efector inc., Exton, Pa., (ifm.com) have developed a solid-state sensor that engineers can add to robots, pick-and-place equipment, machine vision, and a host of other applications to generate 3D images embedded with dimensional data in real time.
The 3D Image Sensor works by bouncing modulated IR light off an object being measured or monitored. Modulated light ensures no other IR source in the vicinity interferes. IR also lets the sensor be used in a wide range of lighting conditions, including full sunlight. The sensor receives light reflected off the object on a 64 × 48-pixel array. Each of the 3,072 pixels preprocesses the incoming signal by computing the phase difference between the reflected and original light sources. Next, the phase data is used to compute the time of flight of each light signal and the distance from the object to each pixel. All this data combines to form a 3D image, which can be displayed as a gray-scale or color-coded distance image.
The device’s sensor and electronics are built onto a 0.25-mm2 silicon chip. This gives the sensor a compact footprint and low power requirements.