[1] [1] M. Faucheux, D. Fayoux, and J. J. Roland, J. Opt. 19, 101 (1988).

[2] [2] S.-W. Song, J.-C. Lee, S.-K. Hong, and D. Chwa, J. Opt. 12, 115501 (2010).

[3] [3] Z. Fan, H. Luo, S. Hu, and G. Xiao, Opt. Eng. 50, 034403 (2011).

[4] [4] F. Aronowitz and R. J. Collins, Appl. Phys. Lett. 9, 55 (1966).

[5] [5] R. Spreeuw, R. C. Neelen, N. Van Druten, E. Eliel, and J. Woerdman, Phys. Rev. A 42, 4315 (1990).

[6] [6] F. Aronowitz, J. Appl. Phys. 41, 2453 (1970).

[7] [7] J. Wu and X. Long, Laser & Infrared (in Chinese) 29, 347 (1999).

[8] [8] L. Cao, Q. Lin, and H. Wang, Aviat. Prec. Manu. Technol. (in Chinese) 29, 8 (1993).

[9] [9] D. R. Jungwirth, "Ring laser cavity backscatter measurement" US Patent 5090812 (1992).

[10] [10] G. Xiao, X. Long, B. Zhang, and G. Li, Chin. Opt. Lett. 9, 101201 (2011).

[11] [11] J. E. Killpatrick, "Laser angular rate sensor" US Patent 3373650 (1968).

[12] [12] W. E. Lamb, Phys. Rev. 134, 1429 (1964).

[13] [13] F. Aronowitz, Phys. Rev. 139, 635 (1965).

[14] [14] F. Aronowitz and J. E. Killpatrick, IEEE J. Quantum Electron. 10, 201 (1974).

[15] [15] B. L. Gao, J. NUDT (in Chinese) S, 1 (1979).

[16] [16] Z. F. Fan, H. Luo, G. F. Lu, and X. Cheng, Proc. SPIE 8192, 81922E (2011).