The invention relates to light-scattering device and method for measuring the
diameter and length of a short carbon nano-tube, wherein the method for measuring the
diameter and length of a short carbon nano-tube comprises the following steps: the light emitted by a
helium-
neon laser becomes a linearly-polarized
laser in a vertical direction via Glan-Taylor
prism; an incident linearly-polarized
laser irradiates on particle samples in a sample
cell after being reflected by a
plane mirror and focused by a lens, the
scattered light in a 90-degree direction generated by the sample particles irradiated by the laser beam orderly enters in two faced pores; the
scattered light is decomposed into a polarized
scattered light in the vertical direction and a polarized scattered light in a horizontal direction via
Wollaston prism; and the polarized scattered lights in the two directions are detected by two photomultipliers respectively, and the measured
light signal is converted to a TTL (
transistor-
transistor logic)
pulse voltage signal and conveyed in a mathematic correlator to obtain the measured
diameter and length. Relative to the most general
microscope measuring method at present, the method for measuring the diameter and length of a short carbon nano-tube is a non-contact measuring method, as well as is fast in measuring speed, low in cost and low in
operational requirements. Relative to Raman spectrometry, the method for measuring the diameter and length of a short carbon nano-tube can measure diameter and length simultaneously, and is suitable for measurement for multi-wall carbon nano-tube.