Enhancement of the transverse excess-noise factor is theoretically predicte
d in optical laser cavities with tilted end mirrors and nonuniform transver
se loss. In particular, it is shown that in a loss-guided laser close to th
e plane-plane geometric instability boundary the excess-noise factor that i
s induced by mirror tilting may largely exceed that predicted for the align
ed cavity. This excess noise is related to beam walk-off induced by mirror
tilting, which makes possible transient amplification of noise in the trans
verse plane. (C) 2000 Optical Society of America OCIS codes: 140.3410, 140.
4780, 270.2500.