Abstract

The emission and transmission properties of three commercially produced coherent fiber optic imaging bundles were evaluated. Full fluorescence excitation versus emission data were collected from 250 to 650nm excitation for high-resolution Sumitomo, Fujikura, and Schott fiber bundles. The results generated show regions of autofluorescence and inelastic Raman scattering in the imaging bundles that represent a wavelength-dependent background signal when these fibers are used for imaging applications. The high-resolution fiber bundles also exhibit significant variation in transmission with the angle of illumination, which affects the overall coupling and transmission efficiency. Knowledge of these properties allows users of high-resolution imaging bundles to optimally design systems that utilize such bundles.

© 2008 Optical Society of America

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References

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  1. G. S. Kino, T. D. Wang, C. H. Contag, M. Mandella, and N. Y. Chan, “Performance of dual axes confocal microscope for in vivo molecular and cellular imaging,” Proc. SPIE 5324, 35-46 (2004).
  2. K. Carlson, M. Chidley, S. Kung Bin, M. Descour, A. Gillenwater, M. Follen, and R. Richards-Kortum, “In vivo fiber-optic confocal reflectance microscope with an injection-molded plastic miniature objective lens,” Appl. Opt. 44, 1792-1797 (2005).
    [CrossRef]
  3. W. Gobel, J. N. D. Kerr, A. Nimmerjahn, and F. Helmchen, “Miniaturized two-photon microscope based on a flexible coherent fiber bundle and a gradient-index lens objective,” Opt. Lett. 29, 2521-2523 (2004).
    [CrossRef]
  4. A. R. Rouse, A. Kano, J. A. Udovich, S. M. Kroto, and A. F. Gmitro, “Design and demonstration of a miniature catheter for a confocal microendoscope,” Appl. Opt. 43, 5763-5771 (2004).
    [CrossRef]
  5. L. Yang, A. M. Raighne, E. M. McCabe, L. A. Dunbar, and T. Scharf, “Confocal microscopy using variable-focal-length microlenses and an optical fiber bundle,” Appl. Opt. 44, 5928-5936 (2005).
    [CrossRef]
  6. T. P. Moffitt and S. A. Prahl, “In vivo sized-fiber spectroscopy,” Proc. SPIE 3917, 225-231 (2000).
  7. R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).
  8. K. L. Reichenbach and C. Xu, “Numerical analysis of light propagation in image fibers or coherent fiber bundles,” Opt. Express 15, 2151-2165 (2007).
    [CrossRef]
  9. M. A. Player, “Spread functions and modulation transfer functions of fibre-optic bundles,” J. Mod. Opt. 35, 1363-1372 (1988).
    [CrossRef]
  10. C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).
  11. A. Komiyama and M. Hashimoto, “A new class of crosstalk in image fibers,” Opt. Commun. 107, 49-53 (1994).
    [CrossRef]
  12. R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).
  13. M. Ohashi, K. Shiraki, and K. Tajima, “Optical loss property of silica-based single mode fibers,” J. Lightwave Technol. 10, 539-543 (1992).
    [CrossRef]
  14. M. Mogi and K. Yoshimura, “Development of super high density packed image guide,” Proc. SPIE 1067, 172-181 (1989).
  15. R. H. Stolen and E. P. Ippen, “Raman gain in glass optical waveguides,” Appl. Phys. Lett. 22, 276-278 (1973).
    [CrossRef]
  16. N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
    [CrossRef]
  17. N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
    [CrossRef]
  18. H. M. Presby, “Ultraviolet-excited fluorescence in optical fibers and preforms,” Appl. Opt. 20, 701-706 (1981).
  19. M. J. Yuen, “Ultraviolet absorption studies of germanium silicate glasses,” Appl. Opt. 21, 136-140 (1982).
  20. J. F. Scott, “Raman Spectra of GeO2,” Phys. Rev. B 1, 3488-3493 (1970).

2007 (1)

2006 (1)

N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
[CrossRef]

2005 (3)

2004 (3)

2000 (3)

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

T. P. Moffitt and S. A. Prahl, “In vivo sized-fiber spectroscopy,” Proc. SPIE 3917, 225-231 (2000).

R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).

1995 (1)

C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).

1994 (1)

A. Komiyama and M. Hashimoto, “A new class of crosstalk in image fibers,” Opt. Commun. 107, 49-53 (1994).
[CrossRef]

1992 (1)

M. Ohashi, K. Shiraki, and K. Tajima, “Optical loss property of silica-based single mode fibers,” J. Lightwave Technol. 10, 539-543 (1992).
[CrossRef]

1989 (1)

M. Mogi and K. Yoshimura, “Development of super high density packed image guide,” Proc. SPIE 1067, 172-181 (1989).

1988 (1)

M. A. Player, “Spread functions and modulation transfer functions of fibre-optic bundles,” J. Mod. Opt. 35, 1363-1372 (1988).
[CrossRef]

1982 (1)

1981 (1)

1973 (1)

R. H. Stolen and E. P. Ippen, “Raman gain in glass optical waveguides,” Appl. Phys. Lett. 22, 276-278 (1973).
[CrossRef]

1970 (1)

J. F. Scott, “Raman Spectra of GeO2,” Phys. Rev. B 1, 3488-3493 (1970).

Bin, S. Kung

Botting, S. K.

N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
[CrossRef]

Brands, W. R.

N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
[CrossRef]

Brewer, M. A.

N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
[CrossRef]

Brookner, C.

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

Carlson, K.

Chan, N. Y.

G. S. Kino, T. D. Wang, C. H. Contag, M. Mandella, and N. Y. Chan, “Performance of dual axes confocal microscope for in vivo molecular and cellular imaging,” Proc. SPIE 5324, 35-46 (2004).

Chidley, M.

Christian, D. D.

C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).

Collier, T.

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

Contag, C. H.

G. S. Kino, T. D. Wang, C. H. Contag, M. Mandella, and N. Y. Chan, “Performance of dual axes confocal microscope for in vivo molecular and cellular imaging,” Proc. SPIE 5324, 35-46 (2004).

Descour, M.

Drezek, R.

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

Drezek, R. A.

N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
[CrossRef]

Dunbar, L. A.

Fatemeh, T.

C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).

Follen, M.

Gillenwater, A.

Gmitro, A. F.

Gobel, W.

Hashimoto, K.

R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).

Hashimoto, M.

A. Komiyama and M. Hashimoto, “A new class of crosstalk in image fibers,” Opt. Commun. 107, 49-53 (1994).
[CrossRef]

Helmchen, F.

Hoying, J. B.

N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
[CrossRef]

Ippen, E. P.

R. H. Stolen and E. P. Ippen, “Raman gain in glass optical waveguides,” Appl. Phys. Lett. 22, 276-278 (1973).
[CrossRef]

Kano, A.

Kerr, J. N. D.

Kino, G. S.

G. S. Kino, T. D. Wang, C. H. Contag, M. Mandella, and N. Y. Chan, “Performance of dual axes confocal microscope for in vivo molecular and cellular imaging,” Proc. SPIE 5324, 35-46 (2004).

Kirkpatrick, N. D.

N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
[CrossRef]

N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
[CrossRef]

Komiyama, A.

A. Komiyama and M. Hashimoto, “A new class of crosstalk in image fibers,” Opt. Commun. 107, 49-53 (1994).
[CrossRef]

Kroto, S. M.

Lotan, R.

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

Malpica, A.

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

Mandella, M.

G. S. Kino, T. D. Wang, C. H. Contag, M. Mandella, and N. Y. Chan, “Performance of dual axes confocal microscope for in vivo molecular and cellular imaging,” Proc. SPIE 5324, 35-46 (2004).

McCabe, E. M.

Moffitt, T. P.

T. P. Moffitt and S. A. Prahl, “In vivo sized-fiber spectroscopy,” Proc. SPIE 3917, 225-231 (2000).

Mogi, M.

M. Mogi and K. Yoshimura, “Development of super high density packed image guide,” Proc. SPIE 1067, 172-181 (1989).

Nakajima, A.

R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).

Nimmerjahn, A.

Ohashi, M.

M. Ohashi, K. Shiraki, and K. Tajima, “Optical loss property of silica-based single mode fibers,” J. Lightwave Technol. 10, 539-543 (1992).
[CrossRef]

Olivier, C.

C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).

Player, M. A.

M. A. Player, “Spread functions and modulation transfer functions of fibre-optic bundles,” J. Mod. Opt. 35, 1363-1372 (1988).
[CrossRef]

Prahl, S. A.

T. P. Moffitt and S. A. Prahl, “In vivo sized-fiber spectroscopy,” Proc. SPIE 3917, 225-231 (2000).

Presby, H. M.

Raighne, A. M.

Ramiro, C.

C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).

Reichenbach, K. L.

Rene-Paul, S.

C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).

Richards-Kortum, R.

K. Carlson, M. Chidley, S. Kung Bin, M. Descour, A. Gillenwater, M. Follen, and R. Richards-Kortum, “In vivo fiber-optic confocal reflectance microscope with an injection-molded plastic miniature objective lens,” Appl. Opt. 44, 1792-1797 (2005).
[CrossRef]

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

Rouse, A. R.

Scharf, T.

Scott, J. F.

J. F. Scott, “Raman Spectra of GeO2,” Phys. Rev. B 1, 3488-3493 (1970).

Shiraki, K.

M. Ohashi, K. Shiraki, and K. Tajima, “Optical loss property of silica-based single mode fibers,” J. Lightwave Technol. 10, 539-543 (1992).
[CrossRef]

Stolen, R. H.

R. H. Stolen and E. P. Ippen, “Raman gain in glass optical waveguides,” Appl. Phys. Lett. 22, 276-278 (1973).
[CrossRef]

Sun, R.-D.

R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).

Tajima, K.

M. Ohashi, K. Shiraki, and K. Tajima, “Optical loss property of silica-based single mode fibers,” J. Lightwave Technol. 10, 539-543 (1992).
[CrossRef]

Udovich, J. A.

Utzinger, U.

N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
[CrossRef]

N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
[CrossRef]

Wang, T. D.

G. S. Kino, T. D. Wang, C. H. Contag, M. Mandella, and N. Y. Chan, “Performance of dual axes confocal microscope for in vivo molecular and cellular imaging,” Proc. SPIE 5324, 35-46 (2004).

Watanabe, I.

R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).

Watanabe, T.

R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).

Weiss, J. A.

N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
[CrossRef]

Xu, C.

Yang, L.

Yoshimura, K.

M. Mogi and K. Yoshimura, “Development of super high density packed image guide,” Proc. SPIE 1067, 172-181 (1989).

Yuen, M. J.

Zou, C.

N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
[CrossRef]

Am. J. Obstet. Gynecol. (1)

R. Drezek, T. Collier, C. Brookner, A. Malpica, R. Lotan, and R. Richards-Kortum, “Laser scanning confocal microscopy of cervical tissue before and after application of acetic acid,” Am. J. Obstet. Gynecol. 182, 1135-1139 (2000).

Appl. Opt. (5)

Appl. Phys. Lett. (1)

R. H. Stolen and E. P. Ippen, “Raman gain in glass optical waveguides,” Appl. Phys. Lett. 22, 276-278 (1973).
[CrossRef]

J Biomed. Opt. (1)

N. D. Kirkpatrick, J. B. Hoying, S. K. Botting, J. A. Weiss, and U. Utzinger, “In vitro model for endogenous optical signatures of collagen,” J Biomed. Opt. 11, 054021 (2006).
[CrossRef]

J. Lightwave Technol. (1)

M. Ohashi, K. Shiraki, and K. Tajima, “Optical loss property of silica-based single mode fibers,” J. Lightwave Technol. 10, 539-543 (1992).
[CrossRef]

J. Mod. Opt. (1)

M. A. Player, “Spread functions and modulation transfer functions of fibre-optic bundles,” J. Mod. Opt. 35, 1363-1372 (1988).
[CrossRef]

J. Photochem. Photobiol., A (1)

R.-D. Sun, A. Nakajima, I. Watanabe, T. Watanabe, and K. Hashimoto, “TiO2-coated optical fiber bundles used as a photocatalytic filter for decomposition of gaseous organic compounds,” J. Photochem. Photobiol., A 136, 111-116 (2000).

Opt. Commun. (1)

A. Komiyama and M. Hashimoto, “A new class of crosstalk in image fibers,” Opt. Commun. 107, 49-53 (1994).
[CrossRef]

Opt. Eng. (1)

C. Ramiro, C. Olivier, D. D. Christian, T. Fatemeh, and S. Rene-Paul, “Measurements of the point spread function for multicore fibers used as image guides in microendoscopy,” Opt. Eng. 34, 2092-2102 (1995).

Opt. Express (1)

Opt. Lett. (1)

Photochem. Photobiol. (1)

N. D. Kirkpatrick, C. Zou, M. A. Brewer, W. R. Brands, R. A. Drezek, and U. Utzinger, “Endogenous fluorescence spectroscopy of cell suspensions for chemopreventive drug monitoring,” Photochem. Photobiol. 81, 125-134 (2005).
[CrossRef]

Phys. Rev. B (1)

J. F. Scott, “Raman Spectra of GeO2,” Phys. Rev. B 1, 3488-3493 (1970).

Proc. SPIE (3)

G. S. Kino, T. D. Wang, C. H. Contag, M. Mandella, and N. Y. Chan, “Performance of dual axes confocal microscope for in vivo molecular and cellular imaging,” Proc. SPIE 5324, 35-46 (2004).

M. Mogi and K. Yoshimura, “Development of super high density packed image guide,” Proc. SPIE 1067, 172-181 (1989).

T. P. Moffitt and S. A. Prahl, “In vivo sized-fiber spectroscopy,” Proc. SPIE 3917, 225-231 (2000).

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Figures (10)

Fig. 1
Fig. 1

Experimental configuration for measurement of fiber bundle EEMs. Excitation bandwidths are selected by a monochromator from a Xe lamp. (a) Three excitation and four detection fibers are coupled to a low-autofluorescence quartz probe. (b) The quartz probe and test fiber bundle (c) are oriented to be as close as possible without physically touching inside of a lighttight box. Fluorescence backscattered from the test fiber is recoupled into the quartz probe and detected by a PMT in the spectrometer.

Fig. 2
Fig. 2

Experimental setup for high-resolution emission measurement with 488 nm excitation light.

Fig. 3
Fig. 3

Backscattered fluorescence and Raman scatter in imaging bundles. (a) Sumitomo IGN-08/30 bundle illuminated with 488 light and imaged with a 515 / 30 nm bandpass emission filter. (b) Fujikura FIGH-30-850N and (c) Schott fiber imaged with the same configuration. Individual cores are much larger and more regularly shaped in the Schott bundle. (d) Same Sumitomo fiber with excitation from 450 to 490 nm with a 520 nm long-pass filter. (e) Fujikura and (f) Schott fiber in the same configuration as (d). Gains were kept constant in images (a)–(c) and (d)–(f) to show the relative level of autofluorescence among the fiber bundles in these wavelength ranges. Each image is 60 μm on a side

Fig. 4
Fig. 4

(a) EEM of the Sumitomo fiber imaging bundle. The majority of autofluorescence is found in the UV excitation range. (b) EEM of the Fujikura fiber with spectral characteristics similar to the Sumitomo fiber but more fluorescence from 600 to 700 nm at λ ex = 380 nm . (c) Schott EEM showing broad fluorescence in the UV region. For the Schott fiber, the display scale has been increased by a factor of 10. For each EEM the scale bar represents the fluorescence intensity, with lighter colors signifying a higher signal on a log scale. Changes from solid to dashed curves in the contour plot represent factor of 10 changes in detected signal.

Fig. 5
Fig. 5

(a) Emission spectra for Sumitomo and Fujikura fiber bundles at λ ex = 265 nm . Peaks occur at similar locations for both fibers consistent with fused silica fibers. (b) Emission spectra at λ ex = 350 nm . Little spectral shift was observed between fibers. (c) Emission spectra at λ ex = 380 nm . The Sumitomo fiber exhibited a slight redshift in the peak at 415 420 nm (main figure). The Fujikura fiber had over 10 times more signal than the Sumitomo fiber at 680 nm (inset) despite having only five times more signal in the 415–420 region (main figure). (d) Emission spectra at λ ex = 488 nm with low signal beyond the visible excitation tail at 500 nm . Significant signal was observed in the Fujikura spectra past 600 nm emission.

Fig. 6
Fig. 6

(a) High-resolution EEM of the Sumitomo imaging fiber with 1 nm excitation–emission slits. A peak can be observed at all excitation wavelengths at a similar distance from the incident wavelength (arrows). (b) The EEM for the Fujikura imaging fiber results in a ridge of signal (arrows) similar to that seen in Fig. 4a. (c) Background measurement on a quartz slide shows little signal in common with the fiber imaging bundles. For the quartz slide, the display scale has been reduced by a factor of 10.

Fig. 7
Fig. 7

(a) High-resolution spectra from the Sumitomo and Fujikura fibers at λ inc = 488 plotted as a function of the wavenumber. (b) Measured spectra at five incident wavelengths ( λ inc = 390 , 410 , 467 , 488 , 540   nm ). The peak decreases in intensity (intensity values plotted without normalization) and slightly shifts with increasing incident wavelength.

Fig. 8
Fig. 8

Emission spectra for a single line of excitation at λ = 488 nm : (a) Sumitomo, (b) Fujikura, (c), (d) Schott fiber. Laser power was kept constant for (a)–(c) and increased in (d) to account for higher fiber losses.

Fig. 9
Fig. 9

Ratio of Raman signal to laser power for multiple lengths of fiber at λ = 488 nm and λ = 633 nm . Error bars represent two standard deviations over multiple measurements

Fig. 10
Fig. 10

Transmission of fiber optic imaging bundles versus angle for (a) Sumitomo, (b) Fujikura, and (c) Schott imaging bundles. The maximum of 1.0 corresponds to the highest on-axis transmission for each of the bundles. For Sumitomo and Fujikura fibers, on-axis transmission was approximately 70% compared with no fiber bundle. For the Schott bundle, this value was 30%.

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