Measurement of Progressive Addition Lens´ Power Using Moire Deflection Technology

Relationship between moire fringes´ tilting angle and power of the progressive addition lens (PAL) is discussed. Optical path of the experiment is shown, and images of moire fringes and measuring results of single lenses and PAL are given. Three dimensional distribution graph of the PAL´s power is provided. Meanwhile, two power distribution lines through the PAL´s corridor obtained respectively using MDT and by focimeter are presented, and the two lines are nearly uniform. It can be verified that one-time measurement of lenses´ power using MDT, especially to those lenses with complicated power distribution, can be implemented and has high measuring precision.