A simple and novel heterodyne interferometer scheme with spatially separated input beams was proposed to minimize the periodic non-linearity. A polarizing beam displacer (PBD) was designed to split the input beams to parallel outputs with orthogonal polarization or combine them which provided symmetric structure for the interferometer. The novel optical setup suppressed the non-linearity caused by the frequency-mixing. Potential use in the measurement of micro displacement or vibration of the new interferometer will be demonstrated.
A roll-angle measurement interferometer with good stability and high sensitivity is presented. In the system, two sets of spatial parallel beams with different frequencies are formed with the help of a Koster prism, a corner cube, a quarter-wave plate, a wedge prism, and a wedge mirror. The wedge prism is used for the roll-angle sensing component, the roll of which will cause the changes of the optical path of the two beams with different frequencies. This interferometer complies with the principle of common path which minimizes the dead path; the cross talk of straightness, pitch, and yaw errors are avoided in this specific structure which enhances the stability and precision of the measurement. The experimental result fits well with the theoretical analysis and a measurement resolution of 2 μrad is achieved with an electronic interpolation of 2π/512.
A roll angle interferometer with high sensitivity is designed in this paper. Two sets of centrosymmetric beams are used to travel through the measurement and reference arms of the roll angle interferometer which contains two specific optical devices: wedge prism assembly and wedge mirror assembly. The optical path change in both arms caused by roll is converted into phase shift which can be measured by interferometer. Because of the adoption of the centrosymmetric measurement structure, the straightness errors, yaw error and pitch error can be avoided and the dead path is minimized, so that the stability and the accuracy of the measurement can be greatly enhanced. The resolution for the roll measurement is about 0.006″ with the measurement range of ±1°.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.