NASA’s Goddard Space Flight Center has developed a non-scanning, 3D imaging laser system that uses a simple lens system to simultaneously generate a one-dimensional or two-dimensional array of optical (light) spots to illuminate an object, surface, or image to generate a topographic profile.
The system includes a microlens array configured in combination with a spherical lens to generate a uniform array for a two-dimensional detector, an optical receiver, and a pulsed laser as the transmitter light source. The pulsed laser travels to and from the light source and the object. A fraction of the light is imaged using the optical detector, and a threshold detector is used to determine the time of day when the pulse arrived at the detector (using picosecond to nanosecond precision). Distance information can be determined for each pixel in the array, which can then be displayed to form a three-dimensional image.
Real-time three-dimensional images are produced with the system at television frame rates (30 frames per second) or higher. Alternate embodiments of this innovation include the use of a light emitting diode in place of a pulsed laser, and/or a macrolens array in place of a microlens.
This system boasts a simple design; it does not require scanning or moving parts to produce high-resolution images. In addition, using a microlens to generate an array of equal intensity and the physical separation of spots in the object plane improve efficiency and reduce crosstalk between pixels. Potential applications include remote sensing (i.e., LiDAR mapping), machine vision, and robotic vision.