The invention belongs to the technical field of 
optical imaging and detecting and relates to a bilateral 
dislocation differential 
confocal element parameter measuring method. The method includes the steps that 
dislocation differential subtracting 
processing is conducted on the two sides of a 
confocal axial characteristic 
data set measured by the starting points and the ending points of all various size parameters including the curvature 
radius, the 
lens thickness, the refractive rate, the focal distance and the interval, and therefore the positioning precision of the starting points and the ending points of the size parameters is improved, and the measuring precision of optical elements of the curvature 
radius, the 
lens thickness, the refractive rate, the focal distance, the interval and the like is improved. According to the bilateral 
dislocation differential 
confocal element parameter measuring method, due to the fact that two sections of data, close to the position of the 
full width at half maximum and very sensitive to 
axial displacement, of a confocal characteristic curve are used for conducting the dislocation differential subtracting 
processing, the position, calculated by the data sections, of the extreme point of the confocal characteristic curve is more sensitive and more accurate than the position, calculated through an existing confocal characteristic curve top fitting method, of the extreme point of the confocal characteristic curve, according to the result of the bilateral dislocation differential confocal element parameter measuring method, under the condition that the confocal element parameter 
system structure is not changed, the axial focusing capability, the 
signal-to-
noise ratio and the like of the 
system can be obviously improved.