In short, apply cotton thread to the outer can for 20 seconds, and use a microscope to measure the volume of tears, which is expressed in millimeters of the line that is reddened by tears
In short, apply the cotton wire to the outside can for 20 seconds and use a microscope to measure the volume of the tears, expressed in the millimeters of the line that is reddened by the tears
In short, a cotton thread is applied to the outer can for 20 seconds, and the volume of tears is measured with a microscope, which is expressed in millimeters of the line reddened by tears<br>