A small, simple device is designed which makes transmission holograms of arbitrarily large objects coated with a retro-reflective paint. It allows direct readout of (delta) Z values from observed interferometric fringes under double-exposure, time-averaged, or real-time conditions. Three such orthogonal devices can be used for simultaneous detection of (delta) x, (delta) y, and (delta) z displacements.
Tung H. Jeong, Tung H. Jeong,
"Modular device for direct holographic measurements", Proc. SPIE 2333, Fifth International Symposium on Display Holography, (17 February 1995); doi: 10.1117/12.201921; https://doi.org/10.1117/12.201921