Abstract

We propose a new signal-processing method for eliminating measurement errors that occur in the wavelength-multiplexed phase-locked laser diode interferometer. The basic idea proposed here is a very simple but effective way to improve measurement accuracy. With our scheme, the phase in the interference signal is strictly shifted by 2π, which enables us to eliminate measurement errors. The equivalent wavelength Λ is 80 mm, and the measurement accuracy reaches ∼Λ/600. A step-height measurement was also carried out in the experiment.

© 1997 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. J. C. Wyant, “Testing aspherics using two-wavelength holography,” Appl. Opt. 10, 2113–2118 (1971).
    [CrossRef] [PubMed]
  2. Y.-Y. Cheng, J. C. Wyant, “Two-wavelength phase shifting interferometry,” Appl. Opt. 23, 4539–4543 (1984).
    [CrossRef] [PubMed]
  3. A. F. Fercher, H. Z. Hu, U. Vry, “Rough surface interferometry with a two-wavelength heterodyne speckle interferometer,” Appl. Opt. 24, 2181–2188 (1985).
    [CrossRef] [PubMed]
  4. K. Creath, “Step height measurement using two-wavelength phase-shifting interferometry,” Appl. Opt. 26, 2810–2816 (1987).
    [CrossRef] [PubMed]
  5. A. J. den Boef, “Two-wavelength scanning spot interferometer using single-frequency diode lasers,” Appl. Opt. 27, 306–311 (1988).
    [CrossRef]
  6. O. Sasaki, H. Sasazaki, T. Suzuki, “Two-wavelength sinusoidal phase/modulating laser diode interferometer sensitive to external disturbances,” Appl. Opt. 30, 4040–4045 (1991).
    [CrossRef] [PubMed]
  7. Y. Ishii, R. Onodera, “Two-wavelength laser-diode interferometry that uses phase-shifting techniques,” Opt. Lett. 16, 1523–1525 (1991).
    [CrossRef] [PubMed]
  8. P. de Groot, S. Kishner, “Synthetic wavelength stabilization for two-color laser-diode interferometry,” Appl. Opt. 30, 4026–4033 (1991).
    [CrossRef] [PubMed]
  9. C. C. Williams, K. Wickramasinghe, “Optical ranging by wavelength multiplexed interferometry,” J. Appl. Phys. 60, 1900–1903 (1986).
    [CrossRef]
  10. T. Suzuki, O. Sasaki, T. Maruyama, “Absolute distance measurement using wavelength-multiplexed phase-locked laser diode interferometry,” Opt. Eng. 35, 492–497 (1996).
    [CrossRef]
  11. G. W. Johonson, D. C. Leiner, D. T. Moore, “Phase-locked interferometry,” Opt. Eng. 18, 46–52 (1979).
  12. H. J. Matthews, D. K. Hamilton, C. J. R. Sheppard, “Surface profiling by phase-locked interferometry,” Appl. Opt. 25, 2372–2374 (1986).
    [CrossRef] [PubMed]
  13. T. Suzuki, O. Sasaki, T. Maruyama, “Phase locked laser diode interferometry for surface profile measurement,” Appl. Opt. 28, 4407–4410 (1989).
    [CrossRef] [PubMed]
  14. O. Sasaki, K. Takahashi, T. Suzuki, “Sinusoidal phase modulating laser diode interferometer with a feedback control system to eliminate external disturbance,” Opt. Eng. 29, 1511–1515 (1990).
    [CrossRef]
  15. T. Suzuki, O. Sasaki, K. Higuchi, T. Maruyama, “Differential type of phase-locked laser diode interferometer free from external disturbance,” Appl. Opt. 31, 7242–7248 (1992).
    [CrossRef] [PubMed]

1996

T. Suzuki, O. Sasaki, T. Maruyama, “Absolute distance measurement using wavelength-multiplexed phase-locked laser diode interferometry,” Opt. Eng. 35, 492–497 (1996).
[CrossRef]

1992

1991

1990

O. Sasaki, K. Takahashi, T. Suzuki, “Sinusoidal phase modulating laser diode interferometer with a feedback control system to eliminate external disturbance,” Opt. Eng. 29, 1511–1515 (1990).
[CrossRef]

1989

1988

1987

1986

C. C. Williams, K. Wickramasinghe, “Optical ranging by wavelength multiplexed interferometry,” J. Appl. Phys. 60, 1900–1903 (1986).
[CrossRef]

H. J. Matthews, D. K. Hamilton, C. J. R. Sheppard, “Surface profiling by phase-locked interferometry,” Appl. Opt. 25, 2372–2374 (1986).
[CrossRef] [PubMed]

1985

1984

1979

G. W. Johonson, D. C. Leiner, D. T. Moore, “Phase-locked interferometry,” Opt. Eng. 18, 46–52 (1979).

1971

Cheng, Y.-Y.

Creath, K.

de Groot, P.

den Boef, A. J.

Fercher, A. F.

Hamilton, D. K.

Higuchi, K.

Hu, H. Z.

Ishii, Y.

Johonson, G. W.

G. W. Johonson, D. C. Leiner, D. T. Moore, “Phase-locked interferometry,” Opt. Eng. 18, 46–52 (1979).

Kishner, S.

Leiner, D. C.

G. W. Johonson, D. C. Leiner, D. T. Moore, “Phase-locked interferometry,” Opt. Eng. 18, 46–52 (1979).

Maruyama, T.

Matthews, H. J.

Moore, D. T.

G. W. Johonson, D. C. Leiner, D. T. Moore, “Phase-locked interferometry,” Opt. Eng. 18, 46–52 (1979).

Onodera, R.

Sasaki, O.

Sasazaki, H.

Sheppard, C. J. R.

Suzuki, T.

Takahashi, K.

O. Sasaki, K. Takahashi, T. Suzuki, “Sinusoidal phase modulating laser diode interferometer with a feedback control system to eliminate external disturbance,” Opt. Eng. 29, 1511–1515 (1990).
[CrossRef]

Vry, U.

Wickramasinghe, K.

C. C. Williams, K. Wickramasinghe, “Optical ranging by wavelength multiplexed interferometry,” J. Appl. Phys. 60, 1900–1903 (1986).
[CrossRef]

Williams, C. C.

C. C. Williams, K. Wickramasinghe, “Optical ranging by wavelength multiplexed interferometry,” J. Appl. Phys. 60, 1900–1903 (1986).
[CrossRef]

Wyant, J. C.

Appl. Opt.

Y.-Y. Cheng, J. C. Wyant, “Two-wavelength phase shifting interferometry,” Appl. Opt. 23, 4539–4543 (1984).
[CrossRef] [PubMed]

A. F. Fercher, H. Z. Hu, U. Vry, “Rough surface interferometry with a two-wavelength heterodyne speckle interferometer,” Appl. Opt. 24, 2181–2188 (1985).
[CrossRef] [PubMed]

H. J. Matthews, D. K. Hamilton, C. J. R. Sheppard, “Surface profiling by phase-locked interferometry,” Appl. Opt. 25, 2372–2374 (1986).
[CrossRef] [PubMed]

K. Creath, “Step height measurement using two-wavelength phase-shifting interferometry,” Appl. Opt. 26, 2810–2816 (1987).
[CrossRef] [PubMed]

A. J. den Boef, “Two-wavelength scanning spot interferometer using single-frequency diode lasers,” Appl. Opt. 27, 306–311 (1988).
[CrossRef]

T. Suzuki, O. Sasaki, T. Maruyama, “Phase locked laser diode interferometry for surface profile measurement,” Appl. Opt. 28, 4407–4410 (1989).
[CrossRef] [PubMed]

P. de Groot, S. Kishner, “Synthetic wavelength stabilization for two-color laser-diode interferometry,” Appl. Opt. 30, 4026–4033 (1991).
[CrossRef] [PubMed]

O. Sasaki, H. Sasazaki, T. Suzuki, “Two-wavelength sinusoidal phase/modulating laser diode interferometer sensitive to external disturbances,” Appl. Opt. 30, 4040–4045 (1991).
[CrossRef] [PubMed]

T. Suzuki, O. Sasaki, K. Higuchi, T. Maruyama, “Differential type of phase-locked laser diode interferometer free from external disturbance,” Appl. Opt. 31, 7242–7248 (1992).
[CrossRef] [PubMed]

J. C. Wyant, “Testing aspherics using two-wavelength holography,” Appl. Opt. 10, 2113–2118 (1971).
[CrossRef] [PubMed]

J. Appl. Phys.

C. C. Williams, K. Wickramasinghe, “Optical ranging by wavelength multiplexed interferometry,” J. Appl. Phys. 60, 1900–1903 (1986).
[CrossRef]

Opt. Eng.

T. Suzuki, O. Sasaki, T. Maruyama, “Absolute distance measurement using wavelength-multiplexed phase-locked laser diode interferometry,” Opt. Eng. 35, 492–497 (1996).
[CrossRef]

G. W. Johonson, D. C. Leiner, D. T. Moore, “Phase-locked interferometry,” Opt. Eng. 18, 46–52 (1979).

O. Sasaki, K. Takahashi, T. Suzuki, “Sinusoidal phase modulating laser diode interferometer with a feedback control system to eliminate external disturbance,” Opt. Eng. 29, 1511–1515 (1990).
[CrossRef]

Opt. Lett.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (7)

Fig. 1
Fig. 1

Experimental setup of the wavelength-multiplexed phase-locked LD interferometer by using a phase-shifting technique. Feedback current I1 or I2 generated by the feedback controller (FBC) is injected into the LD through the LD modulator (LM). The FBC consists of a feedback signal generator (FBSG), a feedback signal transition controller (TRN), two PI controllers, a timing controller (TC), a switch (SW), and a voltage-to-current converter (VI). OSC, oscillator.

Fig. 2
Fig. 2

Feedback signals in (a) the ideal case and (b) the actual case that contains offset voltage VO. Although the phase difference between P1 and P3 in (b) becomes larger than that in (a), the phase difference between P1 and P2 is the same in both cases.

Fig. 3
Fig. 3

Phase-shifting process according to the transition of feedback signal F2(α). Only the transition of feedback signal F2(α) is shown.

Fig. 4
Fig. 4

Block diagram of the feedback signal transition controller TRN. It consists of two analog switches, SW1 and SW2; a sign converter; transition–timing control logic; and two sample–hold circuits, S/H1 and S/H2.

Fig. 5
Fig. 5

Observed control voltages corresponding to the feedback signal shown in Fig. 3. The difference ΔV becomes large as the feedback signal is changed.

Fig. 6
Fig. 6

Measured absolute distance. The object mirror M2 was moved in discrete 0.5-mm increments.

Fig. 7
Fig. 7

Measured step height of the block gauge whose thickness was ∼2 mm. The measured values are represented by circles.

Equations (13)

Equations on this page are rendered with MathJax. Learn more.

Imt=a cosωct+θ,
St, x=S1+S0 cosz cosωct+θ+αx,
z=4πaβD0/λ02
αx=4πD0x/λ0
α1x=4πD0x/λ1,
α2x=4πD0x/λ2,
Δαx=4πD0x/Λ,
Λ=λ1λ2/λ1-λ2
D0x=Λ4πΔαx.
D0x=CΔαxΔV,
pix=T/4i-1T/4iSt, xdt i=14,
Fsαx=p1+p2-p3-p4=As sin αx,
Fcαx=p1-p2+p3-p4=Ac sin αx,

Metrics