Abstract

We analyze the three most common profiles of scanning functions for galvanometer-based scanners (GSs): the sawtooth, triangular and sinusoidal functions. They are determined experimentally with regard to the scan parameters of the input signal (i.e., frequency and amplitude). We study the differences of the output function of the GS measured as the positional error of the oscillatory mirror from the ideal function given by the input signal of the device. The limits in achieving the different types of scanning functions in terms of duty cycle and linearity are determined experimentally for the possible range of scan parameters. Of particular importance are the preservation of an imposed duty cycle and profile for the sawtooth function, the quantification of the linearity for the sinusoidal function, and the effective duty cycle for the triangular, as well as for the other functions. The range of scan amplitudes for which the stability of the oscillatory regime of the galvo mirror is stable for different frequencies is also highlighted. While the use of the device in certain scanning regimes is studied, certain rules of thumb are deduced to make the best out of the galvoscanner. Finally, the three types of scanning functions are tested with a Fourier domain optical coherence tomography (FD OCT) setup and the conclusions of the study are demonstrated in an imaging application by correlating the determined limits of the scanning regimes with the requirements of OCT.

© 2011 Optical Society of America

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References

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    [CrossRef]
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  6. B. E. Rohr, “Testing high-performance galvanometer-based optical scanners,” Proc. SPIE 2383, 460–469 (1995).
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2010 (7)

2009 (2)

2008 (3)

2007 (3)

2006 (1)

2005 (4)

2004 (1)

1999 (3)

R. P. Aylward, “Advances and technologies of galvanometer-based optical scanners,” Proc. SPIE 3787, 158–164 (1999).
[CrossRef]

K. H. Kim, C. Buehler, and P. T. C. So, “High-speed, two-photon scanning microscope,” Appl. Opt. 38, 6004–6009(1999).
[CrossRef]

J. S. Gadhok, “Achieving high-duty cycle sawtooth scanning with galvanometric scanners,” Proc. SPIE 3787, 173–180(1999).
[CrossRef]

1997 (1)

M. N. Sweeney, “Polygon scanners revisited,” Proc. SPIE 3131, 65–76 (1997).
[CrossRef]

1995 (2)

L. Beiser, “Fundamental architecture of optical scanning systems,” Appl. Opt. 34, 7307–7317 (1995).
[CrossRef] [PubMed]

B. E. Rohr, “Testing high-performance galvanometer-based optical scanners,” Proc. SPIE 2383, 460–469 (1995).
[CrossRef]

Akcay, A. C.

Aylward, R. P.

R. P. Aylward, “Advances and technologies of galvanometer-based optical scanners,” Proc. SPIE 3787, 158–164 (1999).
[CrossRef]

Basavanhally, A. N.

M. W. Jenkins, O. Q. Chughtai, A. N. Basavanhally, M. Watanabe, and A. M. Rollins, “In vivo gated 4D imaging of the embryonic heart using optical coherence tomography,” J. Biomed. Opt. 12, 030505 (2007).
[CrossRef] [PubMed]

Baumann, B.

Beiser, L.

L. Beiser, “Fundamental architecture of optical scanning systems,” Appl. Opt. 34, 7307–7317 (1995).
[CrossRef] [PubMed]

L. Beiser and B. Johnson, “Scanners,” in Handbook of Optics, M.Bass, ed. (McGraw-Hill, 1995).

Biedermann, B. R.

Bouma, B. E.

Buehler, C.

Cho, H.

Choi, D.

Chughtai, O. Q.

M. W. Jenkins, O. Q. Chughtai, A. N. Basavanhally, M. Watanabe, and A. M. Rollins, “In vivo gated 4D imaging of the embryonic heart using optical coherence tomography,” J. Biomed. Opt. 12, 030505 (2007).
[CrossRef] [PubMed]

Clarkson, E.

Coleman, S. M.

S. M. Coleman, “High capacity aerodynamic air bearing (HCAB) for laser scanning applications,” Proc. SPIE 5873, 56–64 (2005).
[CrossRef]

Cucu, R. G.

Dallas, W.

Delemos, T.

Delfyett, P. J.

K. Hsu, P. Meemon, K. S. Kee, P. J. Delfyett, and J. P. Rolland, “Broadband Fourier-domain mode-locked lasers,” Photonics Sensors Online First™, 4 November 2010 (2010). http://www.springerlink.com/content/31285878q356621v/fulltext.pdf.

DiMarzio, Ch. A.

Dobre, G. M.

Duan, Z.

Duma, V. F.

V. F. Duma, “Optimal scanning function of a galvanometer scanner for an increased duty cycle,” Opt. Eng. 49, 103001 (2010).
[CrossRef]

V. F. Duma, J. P. Rolland, and A. Gh. Podoleanu, “Perspectives of optical scanning in OCT,” Proc. SPIE 7556, 7556–10(2010).

V. F. Duma and M. Nicolov, “Neutral density filters with Risley prisms: analysis and design,” Appl. Opt. 48, 2678–2685 (2009).
[CrossRef] [PubMed]

V. F. Duma, “Mathematical functions of a 2-D scanner with oscillating elements,” in Dynamic Systems Theory and Applications, J.Awrejcewicz, ed. (Springer, 2009), pp. 243–253.

Eigenwillig, C. M.

Furukawa, H.

Gadhok, J. S.

J. S. Gadhok, “Achieving high-duty cycle sawtooth scanning with galvanometric scanners,” Proc. SPIE 3787, 173–180(1999).
[CrossRef]

Gorczynska, I.

Götzinger, E.

Grulkowski, I.

Hiro-Oka, H.

Hitzenberger, Ch. K.

Hsu, K.

K. S. Lee, P. Meemon, W. Dallas, K. Hsu, and J. P. Rolland, “Dual detection full range frequency domain optical coherence tomography,” Opt. Lett. 35, 1058–1060 (2010).
[CrossRef] [PubMed]

K. Hsu, P. Meemon, K. S. Kee, P. J. Delfyett, and J. P. Rolland, “Broadband Fourier-domain mode-locked lasers,” Photonics Sensors Online First™, 4 November 2010 (2010). http://www.springerlink.com/content/31285878q356621v/fulltext.pdf.

Huang, S.

Huber, R.

Janabi-Sharifi, F.

Jenkins, M. W.

M. W. Jenkins, O. Q. Chughtai, A. N. Basavanhally, M. Watanabe, and A. M. Rollins, “In vivo gated 4D imaging of the embryonic heart using optical coherence tomography,” J. Biomed. Opt. 12, 030505 (2007).
[CrossRef] [PubMed]

Johnson, B.

L. Beiser and B. Johnson, “Scanners,” in Handbook of Optics, M.Bass, ed. (McGraw-Hill, 1995).

Kee, K. S.

K. Hsu, P. Meemon, K. S. Kee, P. J. Delfyett, and J. P. Rolland, “Broadband Fourier-domain mode-locked lasers,” Photonics Sensors Online First™, 4 November 2010 (2010). http://www.springerlink.com/content/31285878q356621v/fulltext.pdf.

Kim, K. H.

Klein, T.

Kowalczyk, A.

Lee, K. S.

Leitgeb, R. A.

Marcos, S.

Marshall, G. F.

G. F. Marshall, Handbook of Optical and Laser Scanning (Marcel Dekker, 2004).
[CrossRef]

Matsushita, Kenji

Meemon, P.

Miyazaki, D.

Montagu, J.

J. Montagu, “Scanners—galvanometric and resonant,” in Encyclopedia of Optical Engineering, R.G.Driggers, C.Hoffman, and R.Driggers, eds. (Taylor & Francis, 2003) pp. 2465–2487.
[CrossRef]

Nakanishi, M.

Nicolov, M.

Oh, W. Y.

Ohbayashi, K.

Ortiz, S.

Pascual, D.

Pircher, M.

Podoleanu, A. Gh.

V. F. Duma, J. P. Rolland, and A. Gh. Podoleanu, “Perspectives of optical scanning in OCT,” Proc. SPIE 7556, 7556–10(2010).

A. Gh. Podoleanu and R. B. Rosen, “Combinations of techniques in imaging the retina with high resolution,” Progr. Retinal Eye Res. 27, 464–499 (2008).
[CrossRef]

C. C. Rosa, J. Rogers, and A. Gh. Podoleanu, “Fast scanning transmissive delay line for optical coherence tomography,” Opt. Lett. 30, 3263–3265 (2005).
[CrossRef]

A. Gh. Podoleanu, G. M. Dobre, and R. G. Cucu, “Sequential optical coherence tomography and confocal imaging,” Opt. Lett. 29, 364–366 (2004).
[CrossRef] [PubMed]

Remon, L.

Rogers, J.

Rohr, B. E.

B. E. Rohr, “Testing high-performance galvanometer-based optical scanners,” Proc. SPIE 2383, 460–469 (1995).
[CrossRef]

Rolland, J. P.

Rollins, A. M.

M. W. Jenkins, O. Q. Chughtai, A. N. Basavanhally, M. Watanabe, and A. M. Rollins, “In vivo gated 4D imaging of the embryonic heart using optical coherence tomography,” J. Biomed. Opt. 12, 030505 (2007).
[CrossRef] [PubMed]

Rosa, C. C.

Rosen, R. B.

A. Gh. Podoleanu and R. B. Rosen, “Combinations of techniques in imaging the retina with high resolution,” Progr. Retinal Eye Res. 27, 464–499 (2008).
[CrossRef]

Shi, Y.

Shiba, K.

Shimizu, K.

Siedlecki, D.

So, P. T. C.

Sotsuka, K.

Sweeney, M. N.

M. N. Sweeney, “Polygon scanners revisited,” Proc. SPIE 3131, 65–76 (1997).
[CrossRef]

Szkulmowska, A.

Szkulmowski, M.

Szlag, D.

Tao, X.

Tearney, G. J.

Warger, W. C.

Watanabe, M.

M. W. Jenkins, O. Q. Chughtai, A. N. Basavanhally, M. Watanabe, and A. M. Rollins, “In vivo gated 4D imaging of the embryonic heart using optical coherence tomography,” J. Biomed. Opt. 12, 030505 (2007).
[CrossRef] [PubMed]

Wen, S.

Wieser, W.

Wojtkowski, M.

Xie, J.

Yoshimura, R.

Yun, S. H.

Appl. Opt. (6)

Biomed. Opt. Express (1)

J. Biomed. Opt. (1)

M. W. Jenkins, O. Q. Chughtai, A. N. Basavanhally, M. Watanabe, and A. M. Rollins, “In vivo gated 4D imaging of the embryonic heart using optical coherence tomography,” J. Biomed. Opt. 12, 030505 (2007).
[CrossRef] [PubMed]

Opt. Eng. (1)

V. F. Duma, “Optimal scanning function of a galvanometer scanner for an increased duty cycle,” Opt. Eng. 49, 103001 (2010).
[CrossRef]

Opt. Express (5)

Opt. Lett. (6)

Proc. SPIE (6)

J. S. Gadhok, “Achieving high-duty cycle sawtooth scanning with galvanometric scanners,” Proc. SPIE 3787, 173–180(1999).
[CrossRef]

S. M. Coleman, “High capacity aerodynamic air bearing (HCAB) for laser scanning applications,” Proc. SPIE 5873, 56–64 (2005).
[CrossRef]

R. P. Aylward, “Advances and technologies of galvanometer-based optical scanners,” Proc. SPIE 3787, 158–164 (1999).
[CrossRef]

B. E. Rohr, “Testing high-performance galvanometer-based optical scanners,” Proc. SPIE 2383, 460–469 (1995).
[CrossRef]

V. F. Duma, J. P. Rolland, and A. Gh. Podoleanu, “Perspectives of optical scanning in OCT,” Proc. SPIE 7556, 7556–10(2010).

M. N. Sweeney, “Polygon scanners revisited,” Proc. SPIE 3131, 65–76 (1997).
[CrossRef]

Progr. Retinal Eye Res. (1)

A. Gh. Podoleanu and R. B. Rosen, “Combinations of techniques in imaging the retina with high resolution,” Progr. Retinal Eye Res. 27, 464–499 (2008).
[CrossRef]

Other (5)

J. Montagu, “Scanners—galvanometric and resonant,” in Encyclopedia of Optical Engineering, R.G.Driggers, C.Hoffman, and R.Driggers, eds. (Taylor & Francis, 2003) pp. 2465–2487.
[CrossRef]

G. F. Marshall, Handbook of Optical and Laser Scanning (Marcel Dekker, 2004).
[CrossRef]

L. Beiser and B. Johnson, “Scanners,” in Handbook of Optics, M.Bass, ed. (McGraw-Hill, 1995).

V. F. Duma, “Mathematical functions of a 2-D scanner with oscillating elements,” in Dynamic Systems Theory and Applications, J.Awrejcewicz, ed. (Springer, 2009), pp. 243–253.

K. Hsu, P. Meemon, K. S. Kee, P. J. Delfyett, and J. P. Rolland, “Broadband Fourier-domain mode-locked lasers,” Photonics Sensors Online First™, 4 November 2010 (2010). http://www.springerlink.com/content/31285878q356621v/fulltext.pdf.

Supplementary Material (7)

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» Media 6: MOV (3307 KB)     
» Media 7: MOV (2447 KB)     

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Figures (19)

Fig. 1
Fig. 1

Experimental stall for the study of the scanning functions of the galvoscanner: FD OCT system with a GS measurement setup.

Fig. 2
Fig. 2

Sawtooth profiles of the scanning functions for the same time period T = 1 / f s of the oscillation process: (a) Triangular (ideal profile, with “sharp” stop-and-turn portions), with duty cycle η equal 50% for unidirectional scan and η equal 100% for bidirectional scan; (b) Sawtooth (asymmetric), with 50 % < η < 100 % ; (c) Ideal sawtooth, with η equal 100% (i.e., full time efficiency); (d) Real profile of the sawtooth scanning function at high frequencies f s (not at scale).

Fig. 3
Fig. 3

Sawtooth scanning functions of the GS for the two values considered for the duty cycles η—columns (1) and (2)—at different scan frequencies ( f s ) and at each frequency for increasing scan amplitudes.

Fig. 4
Fig. 4

Effective duty cycle of the sawtooth scanning function (output signal/mirror position) with regard to the scan amplitude θ m for each scan frequency ( f s )—and for the two duty cycles set for the input signal of the GS: (1)  η 1 equal 75%; (2)  η 2 equal 87.5%.

Fig. 5
Fig. 5

Variation of the θ ( t ) profile when increasing (then decreasing) the scan amplitudes for η 1 : (a)  f s equal 200 Hz (Media 1) 1.95 MB , and (b)  300 Hz (Media 2) 1.16 MB ; for η 2 : (c)  f s equal 200 Hz (Media 3) 2.30 MB , and (d)  300 Hz (Media 4) 2.24 MB .

Fig. 6
Fig. 6

Variation of the θ ( t ) profile when increasing (then decreasing) the scan frequency from 500 Hz to 1 kHz for a scan amplitude proportional to 0.16 V (output signal of the position sensor) for (a)  η 1 (Media 5) 2.15 MB and (b)  η 2 (Media 6) 3.22 MB .

Fig. 7
Fig. 7

Limit amplitudes of the scanning functions with regard to scan frequency f s (i.e., the maximum amplitude at which the oscillatory process of the galvo mirror is still stable): (a) for the sawtooth input with η 2 ; (b) for the triangular and sinusoidal input functions.

Fig. 8
Fig. 8

Real profile of the triangular scanning function at high frequencies f s .

Fig. 9
Fig. 9

Triangular scanning functions of the GS at different scan frequencies ( f s ) and for increasing scan amplitudes.

Fig. 10
Fig. 10

Effective duty cycle of the triangular scanning function with regard to scan frequency ( f s ) for each scan amplitude.

Fig. 11
Fig. 11

Triangular scanning functions—for different scan frequencies f s = 100 ( 1 + k ) , k = 0 9 [ Hz ] : profiles of the functions for the limit amplitudes.

Fig. 12
Fig. 12

Sinusoidal scanning function and nonlinearity error.

Fig. 13
Fig. 13

Experimental sinusoidal scanning functions for f s equal 10 and 300 Hz .

Fig. 14
Fig. 14

Sinusoidal scanning functions—for different scan frequencies f s = 50 ; 100 k , k = 1 9 [ Hz ] : (a) profiles for the limit amplitudes; (b) values of the limit amplitudes.

Fig. 15
Fig. 15

Shape shift from sinusoidal to triangular for the scanning function for an amplitude change at 200 Hz (Media 7) 2.38 MB .

Fig. 16
Fig. 16

FD OCT image of onion, scan with 200 mV amplitude: (a) reference (point-by-point scan, i.e., f s equal 4 Hz ), and raster scanning with f s equal 55.8 Hz , with a scanning profile: (b) triangular; (c) sinusoidal; (d) sawtooth. Scale bar: 200 μm .

Fig. 17
Fig. 17

FD OCT image of onion, scan with the amplitudes of (1)  400 mV ; (2)  800 mV , for: (a) reference (point-by-point scan, i.e., f s equal 4 Hz ), and raster scanning with f s equal 55.8 Hz , with a scanning profile: (b) triangular; (c) sinusoidal. Scale bar: 200 μm .

Fig. 18
Fig. 18

FD OCT image of onion, raster scanning with f s equal 223.2 Hz and with the following amplitudes (1)  200 mV ; (2)  400 mV ; (3)  800 mV , each for (a) triangular; (b) sinusoidal scanning function. Scale bar: 200 μm .

Fig. 19
Fig. 19

Comparison of two FD OCT images of onion cells obtained at the input amplitude θ m = 1.4 V , for the scan frequencies (1)  f s = 100 Hz , and (2)  f s = 500 Hz , with (a) triangular, and (b) sinusoidal input signal. The output signal (the scanning function) profile, which is the other way round, is represented in the graphs that mark each of the images.

Tables (2)

Tables Icon

Table 1 Comparison of the Performances of the Three Scanning Regimes of the Galvoscanner

Tables Icon

Table 2 Duty Cycles η [ % ] Evaluated Approximately from the FD OCT Imaging of Onion Cells for Two Scan Frequencies and Three Scan Amplitudes—from Figs. 16, 17, 18 (in Brackets the Values of η Interpolated for These f s from Fig. 10 are Indicated).

Equations (1)

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η = t a / T .

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