II. Principle of Measurement

Figure 2 shows the RT-Sizer particle size analyzer device diagram, the principle is to produce red laser
light from the light emitting diodes, through beam expander, to expand the laser beam into 9mm
diameter parallel light. The flow field through spray droplets produce light diffraction phenomenon,
and then by the receiver (receiver) of the Fourier lens (Fourier Lens) concentrating the light detector,
Photo Detector is composed of 31 ring light intensity sensor, Can detect different distribution patterns
of spray arising diffracted light, the optical signal conversion via solid crystals into electrical signals,
and then the signal is amplified through the analog to digital signal converter (A / D Converter) is
converted into a digital signal, transmitted to PC, the software arithmetic processing, spray particle
size distribution data can be obtained.
The laboratory used Fourier Lens has two kinds, namely the focal length 100mm (effective measuring
particle size in the range of 0.5μm ~ 200μm) and a focal length of 450mm (effective measuring
particle size in the range of 2.25μm ~ 850μm ) of the Fourier lens.
There is some distance limited between the atomizing air and the Fourier lens, This is to avoid
measurement Cut-off Effect. and the distance between the Fourier lens And atomization gas position
is too large, there will be some small amount of particles undetectable, resulting in measurement
error. Measurement method is to measure the photometry background value first, and then set the
spray measuring time, and automatic measurement times, taking several measurements were
averaged to obtain the measurement data, Analysis of measured raw data (Raw Data) to
Model-Independent method.
III. RT-SizerParticle size analyzer calibration record
i. correction method
In the original standard specimen, type RS-3, comparing the measured diameter error of Dv10、Dv50、Dv90 it.
ii. Revision Date
102/09/20
iii. original correction compared with the measured value of the laboratory

Items	Dv10(μm)	Dv50(μm)	Dv90(μm)
Original correction	21.0±2.5	24.3±2.4	25.0±2.5
measured values	21.17	24.60	24.92
Check results	OK	OK	OK