Classic Microscopy - Baker Interference Binocular Microscope

English, c.1960, engraved Baker, London, complete with 2 substage condenseres, mechanical stage, binocular head - The AO-Baker Interference Microscope uses a birefringent plate and a quarter-wave plate to reunite beams and create plane-polarized light. A rotating analyzer is then used to locate the plane of polarization

you can read about it here: https://www.science-info.net/docs/Smith-Baker/Smith-Baker-Interference.pdf