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These are photos of Kearfott navigational Inertial Reference Units (IRUs) or parts of them that use HeNe laser-based Ring Laser Gyroscopes (RLGs). Only one at present.
See Kearfott Inertial Measurement Unit Assembly 88818-K600A374-01 (Web Album, 24 photos).
The RLUs in this IRU are interesting because all three axes are fabricated in a single block of special low expansion glass or similar material. The accelerometers are totally separate. At present not much else is known other than that the RLGs do power up, but there are no live photos yet.
The last pic shows an ideal application for this IRU. ;-)
Stay tuned.