After removing the low-pass filter, the picture turned red

Yes. Remove the low-pass filter in front of the camera's CMOS and replace it with transparent glass. You can replace the infrared filter with any different band to achieve different infrared effects. The picture will turn red. At present, most mirrorless cameras and SLR cameras basically do not have low-pass filters, which makes it more suitable to install an infrared filter in front of the lens for infrared photography.