The laser altimeter include active transmitter and passive receiver with single pixel detector, the accurate co-alignment of the transmitter to receiver is a challenging task. A facility for axis measurement of transmitter and receiver had to be developed base on pentaprism and two dimensional scanning mechanism．Divide the optical beam before collimator focal plane into two conjugate paths with a pentaprism, one path is for measuring the optical axis of transmitter with beam analyzer. Another path is built with an infrared illuminated aperture stop, scan the two dimensional mechanism under the aperture stop, get the boresight of the receiver by analyzing relationship both detector energy and translation. Error Analysis show that the measurement accuracy of co-alignment of the transmitter to receiver is better than 5″, Prove that the current facility is enough for the alignment of the laser altimeter.
Programmable imager spectrometer can provide flexible data by changing the spectrum section number, central wavelength, spectral width and spatial resolution in orbit. Spectral calibration of imaging spectrometer plays an important role for acquiring accurate spectrum, two spectral calibration types are in essence: wavelength calibration and Full-width-half-maximum (FWHM). Base on the character of programmable imager spectrometer, designed a set of spectral calibration system. Wavelength calibration realized by utilizing the Monochromatic light of high precision monochromator, during the test, changed output parameters of monochromator according to the spectral bandwidth of imager spectrometer. The FWHM is constructed by a set of variable narrow spectrum lines that is output by tunable laser. Gaussian fitting algorithm is used to determine center wavelength and the FWHM of the characteristic spectrum line, Spectral pixels are calibrated by quadratic polynomial, standard spectroscopic lamp is used to verify wavelength calibration result accuracy. The calibration result indicates that FWHM is better than 2nm, the wavelength uncertainty is less than 0.6nm, meet the calibration requirements of programmable imaging spectrometer.