Waveplate

Waveplate, also known as phase retarder, is an optical element that changes the polarization state of light by generating an optical path difference (or phase difference) between two mutually orthogonal polarization components. When the incident light passes through different types of parameter wave plates, the outgoing light is different, which can be linearly polarized light, elliptically polarized light, circularly polarized light, etc.
The main materials of wave plates are birefringent crystals such as quartz, mica, and calcite.
Bohr optics can provide cemented zero-order 1/2 retardation waveplate, cemented zero-order 1/4 retardation waveplate, multi-order 1/2 retardation waveplate, multi-order 1/4 retardation waveplate, etc.
Compound Zero-Order Waveplate, also known as compound waveplate, is to glue two multi-stage waveplates together to eliminate the full-wave optical path difference by aligning the fast axis of one waveplate and the slow axis of the other waveplate. Leave the required optical path difference. Gluing the zero-order waveplate can improve the effect of temperature on the waveplate, but it also increases the sensitivity of the retardation of the waveplate to the incident angle and wavelength.
The thickness of the Multiple-Order Waveplate is equal to the multiple full wave thickness plus a desired retardation thickness. Multistage waveplates are easy to manufacture, but are sensitive to wavelength, temperature, and incident angle.