WOMEN SHAPING HISTORY 2017
Ellen Ochoa, NASA Astronaut
By Adam Sugerman
Ellen Ochoa, NASA Astronaut
Before becoming a NASA astronaut and leader of the Johnson Space Center in Houston, Dr. Ellen Ochoa researched the behavior and characteristics of light while pursuing her graduate degrees at Stanford University and then continued her professional career as an engineer and physicist. She became an expert in the field of optics where she and her colleagues invented as well as filed patents for an optical system that detects defects in repeating patterns, an optical object recognition method that identifies images and targets accurately, and a method for removing noise from images.
With the System for Enhancement of Optical Features, Ochoa and Stanford physicists Joseph Goodman and Lambertus Hesselink created a system that allows cameras to adjust images in real time using advanced laser light. The system allows users to set up optical devices to ignore or enhance elements of an image based on specific detected electromagnetic wavelengths. Prior to this advancement, researchers had to use the time consuming tasks of digital techniques to inspect two-dimensional fields that commonly utilized dual scanning microscope systems along with algorithms to compare and detect patterns.
While working at the Sandia National Laboratories, Ochoa, George Schils, and Donald Sweeney, developed the Position, Rotation, and Intensity Invariant Recognizing Method which allows devices to identify images and targets accurately by using data they receive from objects’ movement and light output. This method expanded the use of existing holographic pattern recognition systems that identified targets rapidly by matching it to information already stored in holographic templates. The limitation in the existing system was that the target images had to match the template exactly, including in scale, rotation, and angle of view. With this new method, the target could be identified regardless of position, brightness, and rotation, even in cases where the target is partially blocked from view. A filter was used to dissect the target image and the resulting hologram was recombined and recomposed using an algorithm called spectral integration.
Ochoa collaborated with Sandia’s Jan Allebach and Donald Sweeney to patent the Optical Ranked-Order Filtering Using Threshold Decomposition, which is a method for noise removal in images. This invention allows devices to filter two-dimensional images to the specification of the user by ranking the intensity of image pixels. The user can calibrate the device to remove the noise, which in this case are the parts of the image outside the desired range of intensity, to produce a clearer image. #
