Research On Flare Angle Calibration System For Infrared Earth Sensor With Collimating Lens On High Orbit

The demarcating technique for the earth simulator is a special one for demarcating collimating infrared earth simulator when used in the satellite. The earth angle is the most important index for scale the precision of the earth simulator. When using collimating the earth simulator, the earth angular precision value must be given, and this is very difficult realized in engineering. Now in and out country, this is no way can really measure the earth angular, and this only can be realized in optical calculation, so this is a "wait for" solve problem for demarcating the angular of the earth simulator.Overall structure, composition and measurement principle of the calibration system for flare angle are described in this paper, and the design method for small field of view infrared probe the key component to calibrate the flare angle is discussed and analyzed detailed. Considering the requirement of the flare angle calibration for the earth simulator, field angle of the infrared probe is expected to be better with it smaller. But the diminishment of the field angle can make the signal-to-noise ratio of the device for flare angle calibration reduce, therefore, adopting the method of hyper-hemispherical lens availably settled the difficult problem that the signal-to-noise ratio is excessive low as the field of view for probe is excessive small, the calibration accuracy of flare angle is improved。The earth angular of simulator was tested by the earth angular demarcating system, and the results show that the three earth angular errors less than±0.05°, and the demarcating method is quite right. The field of view for the developed infrared probe which is small field of view is calibrated by experiment. Results indicate that the shape about its field of view is ellipse (approach circle), its size is 0.45°x0.48°, which can meet the requirement of the calibration for flare angle of the earth simulator.