Based on the evaluation system of astronomical infrared detectors, the performance of two InGaAs NIR detectors, liquid nitrogen-cooled and thermoelectric-cooled, was tested using a modified "photon transfer curve" test method. The measured value is 83 e-, which is much higher than the nominal value of 15 e-; the high and low conversion factors of NIRvana are 1.25 ADU/e- and 0.097 ADU/e-, respectively, and the readout noise is 105 e- and 380 e-; the measured value of dark current of NIRvana at the high conversion factor step is 415 e-/s, which is about twice of the nominal value. The theoretical estimate of the signal electron number of the Yunnan Observatory two-meter ring telescope at 1.565μm solar magnetic field measurement is about 8800 e-, and the NIRvana-LN detector signal-to-noise ratio is 70 under the measured dark current of 4.06 e-/s, image exposure time of 20 ms, and readout noise of 83.59 e-.