Why does the LS122 Infrared Power Meter Show Negative Rejection Rate?

The Linshang LS122 infrared power meter is a wide-line infrared power measuring instrument with a spectral response range of 1000nm-1700nm. The instrument is mainly used for infrared irradiance test and thermal insulation effect demonstration or infrared rejection rate test of insulating glass, thermal insulation film, etc. It can also be used to measure the radiant energy power density test of infrared rays in various light sources.

Some time ago, some customers reported that the rejection rate of Linshang LS122 infrared power metershow a negative number. So what is going on? In fact, it is not a problem with our instruments, it is a problem caused by the sequence of operations. There are two main solutions:
    1.Turn on the light after the position of the instrument and the light source is fixed. Do not put the test material, press the 0% button. At this time, the value on the instrument indicates the light intensity received by the instrument when there is no test material. And the rejection rate is 0%.
    2.Keep the light source and the instrument in place and put in the test material. The value displayed on the instrument indicates the light intensity received by the instrument after the material is placed. And the lower left corner is the rejection rate of the tested material.
    Here we introduce the correct operation of the LS122 infrared power meter:
    1.After fixing the lamp and light source (without the test material in the middle), turn on the infrared light and the instrument.
    2.After turning on the light, the instrument measures the intensity of the infrared light and displays the infrared light intensity data on the instrument.
    3.Press the “0%” button on the instrument before placing the tested material and set the current value to a rejection rate of 0%.
    4.Keep the position of the instrument and lamp unchanged. Place the test sample in the middle of the lamp and the instrument. Infrared data will be displayed on the instrument after the sample is placed. The infrared rejection rate of the material will be displayed in the lower left corner of the screen.
   The above is the correct operation method of Linshang LS122 infrared power meter. This instrument has a wide range of applications. It is suitable for infrared barrier performance testing of solar film, architectural film, automotive insulation film, insulating glass. It can also be used to test the radiation intensity and infrared power density of infrared light source (sun, infrared light, etc.). We hope that the introduction can help you with the selection of the product.