Re: IRS question
(possibly off thread)
ICT
Correct up to a point. No rotation, no moving fringes would, IIRC, be the correct statement. A Sagnac Interferometer (general case of Ring Laser Gyro) won't output if there is no movement of the interference pattern. There will, AFAIAA, be no change in the intereference pattern without an apparent path length difference, and there will be no path length difference without rotation. Unless there are some quantam physics properties that override simple mechanical maths, then there would appear to be no way that this rotational sensor could also sense a linear translation. I stand, as always, to be corrected.
edited to insert "moving" into the phrase 'no fringes'
Last edited by cribble; 16th January 2006 at 06:27.