Super-resolution Measurement Of Fiber Position In Digital Image Processing

This work is a sub-project of LAMOST (Large Area Multi-Object Fiber Spectroscope Telescope) project, which is ongoing in National Astronomical Observatories, Chinese Academy of Science. There are 4,000 fiber positioning units on LAMOST's focal plane, and these units are of high precision (<=40 micron). The method of CCD digital image manipulation has been used to measure the position of these fiber units.By considering character of CCD camera and using the method of digital image manipulation, we can imitate and get the images of fiber. Two-dimensional modified moment and Gaussian surface fit are good centering methods to calculate the data of the imitated images. At different levels of CCD camera noise and image size diffusivity, we have compared the centering error between two algorithms. We analyzed the main reasons that produced the centering error, and researched the method how to get the best gateway value in calculating the center position of a fiber image data. By those researches, we designed fiber positioning experiment and the results of the experiment are satisfactory (<10 micron).The research in this paper has established stability foundation not only for designing the measurement system of LAMOST fiber positioning system in the future, but also for those similar works of high precision positioning.