The present invention discloses an alignment method for the
optical axis of a compound wave plate and a device for the same. Two wafers of a compound wave plate to be aligned are arranged on a bracket, and then are mounted on a fixed wave plate chuck and a rotary wave plate chuck respectively; light emitted from a
light source forms
linearly polarized light after passing through a
polarizer; after passing through the compound wave plate to be aligned, the
linearly polarized light become changed in the polarization state; according to the intensity
signal of transmitted beam detected by a
detector, the variation amplitude of the phase
delay fluctuation quantity of the compound wave plate to be aligned can be obtained further; the
relative magnitude of the variation amplitude of the phase
delay fluctuation quantity is compared; and the rotary wave plate chuck is controlled to rotate through an
electric control rotary table until the
optical axis of the compound wave plate is aligned to be in the required precision range. The device comprises the
light source, the
polarizer, the fixed wave plate chuck, the rotary wave plate chuck, a rotary polarization analyzer, the
detector, the
electric control rotary table, a computer, a stepping motor and an
electric control rotary table controller. The method can align the
optical axis of a compound wave plate with high precision, the deviceis simply equipped, and the operation is simple.