An off-axis alignment system in a lithographic projection apparatus uses broadband radiation to illuminate a phase grating on the wafer. The optical fiber resonator includes an optical fiber, one or more optical filters that suppresses the noise light in the resonator, one or more variable optical attenuators that can adjust the loss of the resonator with fast response, and one or more optical gain elements that provide amplification of light to offset part of the losses of the resonator. 1octyl amide derivatives of formula :wherein L, R1 and R2 are as defined herein, or a pharmaceutically acceptable salt thereof; and pharmaceutical compositions and methods using the same.