| 摘要 |
In an optical resonator arrangement, particularly a ring laser gyroscope, a concave mirror 22 and at least one planar mirror 24, 26, 28 are used to guide a laser beam 14, the plane of one of the mirrors being inclined at an angle of between 1 and 3 arc minutes with respect to the plane of the or each other mirror. The laser is tuned by translating the concave mirror substantially in its own plane (which may be inclined itself in one embodiment) so as to alter the length of the laser path. One of mirrors 26 preferably has an aperture for suppressing off-axis modes of oscillation, and this mirror must be translated in its own plane during tuning to realign the aperture to suppress the off-axis modes. Such a ring laser gyroscope may be made very small: the length of each side of the laser path may be less than an inch in length. <IMAGE> |
