Abstract

We present a simple and versatile approach for fabricating terahertz lenses based on compression molding of micropowder polymer materials in a tabletop hydraulic press. To demonstrate the feasibility of this approach, a biconvex lens shape is calculated using a ray-tracing algorithm and lenses based on two different micropowders are fabricated. As the powder materials have different refractive indices, the resulting lenses share the same geometric shape but differ in their respective focal length. The focusing properties of the lenses are evaluated by transversal and sagittal beam profile measurements in a fiber-coupled terahertz time-domain spectroscopy system, confirming the excellent imaging qualities of the compression molded lenses.

© 2011 Optical Society of America

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    [Crossref] [PubMed]
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    [Crossref]
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  11. C. Jördens and M. Koch, “Detection of foreign bodies in chocolate with pulsed terahertz spectroscopy,” Opt. Eng. 47, 037003 (2008).
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    [Crossref]
  35. M. Scheller, S. Wietzke, C. Jansen, and M. Koch, “Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory,” J. Phys. D 42, 065415(2009).
    [Crossref]
  36. C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
    [Crossref]

2011 (1)

2010 (6)

J. Neu, B. Krolla, O. Paul, B. Reinhard, R. Beigang, and M. Rahm, “Metamaterial-based gradient index lens with strong focusing in the THz frequency range,” Opt. Express 18, 27748–27757 (2010).
[Crossref]

J. Lee, K. Lee, H. Park, G. Kang, D.-H. Yu, and K. Kim, “Tunable subwavelength focusing with dispersion-engineered metamaterials in the terahertz regime,” Opt. Lett. 35, 2254–2256 (2010).
[Crossref] [PubMed]

C. Brueckner, G. Notni, and A. Tuennermann, “Optimal arrangement of 90° off-axis parabolic mirrors in THz setups,” Optik (Jena) 121, 113–119 (2010).
[Crossref]

C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg,M. Salhi, M. N. Krumbholz, C. Jördens, T. Hochrein, and M. Koch, “Terahertz imaging: applications and perspectives,” Appl. Opt. 49, E48–E57 (2010).
[Crossref] [PubMed]

P. U. Jepsen, D. G. Cooke, and M. Koch, “Terahertz spectroscopy and imaging—modern techniques and applications,” Laser Photon. Rev. 5, 124–166 (2010).
[Crossref]

C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
[Crossref]

2009 (4)

M. Scheller, C. Jansen, and M. Koch, “Analyzing sub-100 μm samples with transmission terahertz time domain spectroscopy,” Opt. Commun. 282, 1304–1306 (2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

M. Scheller, S. Wietzke, C. Jansen, and M. Koch, “Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory,” J. Phys. D 42, 065415(2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

2008 (4)

2007 (4)

M. Naftaly and R. E. Miles, “Terahertz time-domain spectroscopy for material characterization,” Proc. IEEE 95, 1658–1665 (2007).
[Crossref]

S. Wietzke, C. Jansen, F. Rutza, D. M. Mittleman, and M. Koch, “Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy,” Polym. Test. 26, 614–618 (2007).
[Crossref]

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

J. Chen, Y. Chen, H. Zhao, G. J. Bastiaans, and X.-C. Zhang, “Absorption coefficients of selected explosives and related compounds in the range of 0.1–2.8 THz,” Opt. Express 15, 12060–12067 (2007).
[Crossref] [PubMed]

2006 (3)

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

A. Sengupta, A. Bandyopadhyay, B. F. Bowden, J. A. Harrington, and J. F. Federici, “Characterisation of olefin copolymers using terahertz spectroscopy,” Electron. Lett. 42, 1477–1479 (2006).
[Crossref]

Y. S. Jin, G. J. Kim, and S. G. Jeon, “Terahertz dielectric properties of polymers,” J. Korean Phys. Soc. 49, 513–517 (2006).
[Crossref]

2005 (3)

S. O. Nelson, “Density-permittivity relationships for powdered and granular materials,” IEEE Trans. Instrum. Meas. 54, 2033–2040 (2005).
[Crossref]

A. Y. Yi and A. Jain, “Compression molding of aspherical glass lenses—a combined experimental and numerical analysis,” J. Am. Ceram. Soc. 88, 579–586 (2005).
[Crossref]

T. Yasui, T. Yasuda, K. Sawanaka, and T. Araki, “Terahertz paintmeter for noncontact monitoring of thickness and drying progress in paint film,” Appl. Opt. 44, 6849–6856(2005).
[Crossref] [PubMed]

2004 (1)

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

2003 (1)

2002 (1)

1996 (1)

1990 (2)

Appelquist, I.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Araki, T.

Astley, V.

C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
[Crossref]

Bandyopadhyay, A.

A. Sengupta, A. Bandyopadhyay, B. F. Bowden, J. A. Harrington, and J. F. Federici, “Characterisation of olefin copolymers using terahertz spectroscopy,” Electron. Lett. 42, 1477–1479 (2006).
[Crossref]

Banerjee, D.

Bastiaans, G. J.

Bastian, M.

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

Beigang, R.

Birch, J. R.

J. R. Birch, “The far infrared optical constants of polyethylene,” Infrared Phys. 30, 195–197 (1990).
[Crossref]

Boreman, G.

W. R. Folks, S. K. Pandey, and G. Boreman, “Refractive index at THz frequencies of various plastics,” in Optical Terahertz Science and Technology, OSA Technical Digest Series (CD) (Optical Society of America, 2007), paper MD10.

Bowden, B. F.

A. Sengupta, A. Bandyopadhyay, B. F. Bowden, J. A. Harrington, and J. F. Federici, “Characterisation of olefin copolymers using terahertz spectroscopy,” Electron. Lett. 42, 1477–1479 (2006).
[Crossref]

Brueckner, C.

C. Brueckner, G. Notni, and A. Tuennermann, “Optimal arrangement of 90° off-axis parabolic mirrors in THz setups,” Optik (Jena) 121, 113–119 (2010).
[Crossref]

Chamberlain, M.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Chen, J.

Chen, Y.

Chernovsky, A.

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

Cooke, D. G.

P. U. Jepsen, D. G. Cooke, and M. Koch, “Terahertz spectroscopy and imaging—modern techniques and applications,” Laser Photon. Rev. 5, 124–166 (2010).
[Crossref]

Fattinger, C.

Federici, J. F.

A. Sengupta, A. Bandyopadhyay, B. F. Bowden, J. A. Harrington, and J. F. Federici, “Characterisation of olefin copolymers using terahertz spectroscopy,” Electron. Lett. 42, 1477–1479 (2006).
[Crossref]

Fichter, G.

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

Fischer, B.

B. Fischer, M. Hoffmann, U. P. Jepsen, and M. Walther, “Use of the plastic materials topas and zeonex for biotechnological applications in the terahertz range,” European Patent Application EP1505382 (9 February 2005).

Folks, W. R.

W. R. Folks, S. K. Pandey, and G. Boreman, “Refractive index at THz frequencies of various plastics,” in Optical Terahertz Science and Technology, OSA Technical Digest Series (CD) (Optical Society of America, 2007), paper MD10.

Gallot, G.

Grischkowsky, D.

Harrington, J. A.

A. Sengupta, A. Bandyopadhyay, B. F. Bowden, J. A. Harrington, and J. F. Federici, “Characterisation of olefin copolymers using terahertz spectroscopy,” Electron. Lett. 42, 1477–1479 (2006).
[Crossref]

Hasek, T.

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

Hochrein, T.

C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg,M. Salhi, M. N. Krumbholz, C. Jördens, T. Hochrein, and M. Koch, “Terahertz imaging: applications and perspectives,” Appl. Opt. 49, E48–E57 (2010).
[Crossref] [PubMed]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

Hoffmann, M.

B. Fischer, M. Hoffmann, U. P. Jepsen, and M. Walther, “Use of the plastic materials topas and zeonex for biotechnological applications in the terahertz range,” European Patent Application EP1505382 (9 February 2005).

Hoshina, H.

C. S. Otani, Y. Sasaki, H. Hoshina, M. Yamashita, G. Okazaki, and K. Kawase, “Development of a prototype apparatus for inspecting illicit drugs inside envelopes,” in Proceedings of the Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Terahertz Electronics, 2006 (IEEE, 2006), p. 173.
[Crossref]

Jacobsen, R. H.

Jain, A.

A. Y. Yi and A. Jain, “Compression molding of aspherical glass lenses—a combined experimental and numerical analysis,” J. Am. Ceram. Soc. 88, 579–586 (2005).
[Crossref]

Jansen, C.

C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
[Crossref]

C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg,M. Salhi, M. N. Krumbholz, C. Jördens, T. Hochrein, and M. Koch, “Terahertz imaging: applications and perspectives,” Appl. Opt. 49, E48–E57 (2010).
[Crossref] [PubMed]

M. Scheller, S. Wietzke, C. Jansen, and M. Koch, “Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory,” J. Phys. D 42, 065415(2009).
[Crossref]

M. Scheller, C. Jansen, and M. Koch, “Analyzing sub-100 μm samples with transmission terahertz time domain spectroscopy,” Opt. Commun. 282, 1304–1306 (2009).
[Crossref]

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

S. Wietzke, C. Jansen, F. Rutza, D. M. Mittleman, and M. Koch, “Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy,” Polym. Test. 26, 614–618 (2007).
[Crossref]

C. Jo¨rdens, C. Jansen, and M. Koch, “Terahertz-Volumen-Bauelement,” German Patent Application 10 2008 030 127.A1.

Jeon, S. G.

Y. S. Jin, G. J. Kim, and S. G. Jeon, “Terahertz dielectric properties of polymers,” J. Korean Phys. Soc. 49, 513–517 (2006).
[Crossref]

Jepsen, P. U.

P. U. Jepsen, D. G. Cooke, and M. Koch, “Terahertz spectroscopy and imaging—modern techniques and applications,” Laser Photon. Rev. 5, 124–166 (2010).
[Crossref]

P. U. Jepsen, R. H. Jacobsen, and S. R. Keiding, “Generation and detection of terahertz pulses from biased semiconductor antennas,” J. Opt. Soc. Am. B 13, 2424–2436 (1996).
[Crossref]

Jepsen, U. P.

B. Fischer, M. Hoffmann, U. P. Jepsen, and M. Walther, “Use of the plastic materials topas and zeonex for biotechnological applications in the terahertz range,” European Patent Application EP1505382 (9 February 2005).

Jin, Y. S.

Y. S. Jin, G. J. Kim, and S. G. Jeon, “Terahertz dielectric properties of polymers,” J. Korean Phys. Soc. 49, 513–517 (2006).
[Crossref]

Jo¨rdens, C.

C. Jo¨rdens, C. Jansen, and M. Koch, “Terahertz-Volumen-Bauelement,” German Patent Application 10 2008 030 127.A1.

Joerdens, C.

Jördens, C.

Kang, G.

Kawase, K.

K. Kawase, Y. Ogawa, and Y. Watanabe, “Non-destructive imaging of illicit drugs using spectral fingerprints,” Opt. Express 11, 2549–2554 (2003).
[Crossref] [PubMed]

C. S. Otani, Y. Sasaki, H. Hoshina, M. Yamashita, G. Okazaki, and K. Kawase, “Development of a prototype apparatus for inspecting illicit drugs inside envelopes,” in Proceedings of the Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Terahertz Electronics, 2006 (IEEE, 2006), p. 173.
[Crossref]

Keiding, S.

Keiding, S. R.

Kim, G. J.

Y. S. Jin, G. J. Kim, and S. G. Jeon, “Terahertz dielectric properties of polymers,” J. Korean Phys. Soc. 49, 513–517 (2006).
[Crossref]

Kim, K.

Koch, M.

B. Scherger, C. Joerdens, and M. Koch, “Variable-focus THz lens,” Opt. Express 19, 4528–4535 (2011).
[Crossref] [PubMed]

P. U. Jepsen, D. G. Cooke, and M. Koch, “Terahertz spectroscopy and imaging—modern techniques and applications,” Laser Photon. Rev. 5, 124–166 (2010).
[Crossref]

C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
[Crossref]

C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg,M. Salhi, M. N. Krumbholz, C. Jördens, T. Hochrein, and M. Koch, “Terahertz imaging: applications and perspectives,” Appl. Opt. 49, E48–E57 (2010).
[Crossref] [PubMed]

M. Scheller, S. Wietzke, C. Jansen, and M. Koch, “Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory,” J. Phys. D 42, 065415(2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

M. Scheller, C. Jansen, and M. Koch, “Analyzing sub-100 μm samples with transmission terahertz time domain spectroscopy,” Opt. Commun. 282, 1304–1306 (2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

C. Jördens and M. Koch, “Detection of foreign bodies in chocolate with pulsed terahertz spectroscopy,” Opt. Eng. 47, 037003 (2008).
[Crossref]

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

S. Wietzke, C. Jansen, F. Rutza, D. M. Mittleman, and M. Koch, “Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy,” Polym. Test. 26, 614–618 (2007).
[Crossref]

C. Jo¨rdens, C. Jansen, and M. Koch, “Terahertz-Volumen-Bauelement,” German Patent Application 10 2008 030 127.A1.

Kretschmer, K.

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

Krolla, B.

Krumbholz, M. N.

Krumbholz, N.

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

Kürner, T.

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

Lee, J.

Lee, K.

Leonhardt, R.

Lo, Y. H.

Mikulics, M.

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

Miles, R. E.

M. Naftaly and R. E. Miles, “Terahertz time-domain spectroscopy for material characterization,” Proc. IEEE 95, 1658–1665 (2007).
[Crossref]

Mittleman, D.

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

Mittleman, D. M.

C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
[Crossref]

S. Wietzke, C. Jansen, F. Rutza, D. M. Mittleman, and M. Koch, “Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy,” Polym. Test. 26, 614–618 (2007).
[Crossref]

Naftaly, M.

M. Naftaly and R. E. Miles, “Terahertz time-domain spectroscopy for material characterization,” Proc. IEEE 95, 1658–1665 (2007).
[Crossref]

Nelson, S. O.

S. O. Nelson, “Density-permittivity relationships for powdered and granular materials,” IEEE Trans. Instrum. Meas. 54, 2033–2040 (2005).
[Crossref]

Neu, J.

Newnham, D.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Notni, G.

C. Brueckner, G. Notni, and A. Tuennermann, “Optimal arrangement of 90° off-axis parabolic mirrors in THz setups,” Optik (Jena) 121, 113–119 (2010).
[Crossref]

Ogawa, Y.

Okazaki, G.

C. S. Otani, Y. Sasaki, H. Hoshina, M. Yamashita, G. Okazaki, and K. Kawase, “Development of a prototype apparatus for inspecting illicit drugs inside envelopes,” in Proceedings of the Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Terahertz Electronics, 2006 (IEEE, 2006), p. 173.
[Crossref]

Otani, C. S.

C. S. Otani, Y. Sasaki, H. Hoshina, M. Yamashita, G. Okazaki, and K. Kawase, “Development of a prototype apparatus for inspecting illicit drugs inside envelopes,” in Proceedings of the Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Terahertz Electronics, 2006 (IEEE, 2006), p. 173.
[Crossref]

Pandey, S. K.

W. R. Folks, S. K. Pandey, and G. Boreman, “Refractive index at THz frequencies of various plastics,” in Optical Terahertz Science and Technology, OSA Technical Digest Series (CD) (Optical Society of America, 2007), paper MD10.

Park, H.

Paul, O.

Peters, O.

Phillips, C.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Piesiewicz, R.

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

Planken, P. C. M.

Podzorov, A.

Rahm, M.

Reinhard, B.

Roskos, H.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Roskos, H. G.

Rutza, F.

S. Wietzke, C. Jansen, F. Rutza, D. M. Mittleman, and M. Koch, “Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy,” Polym. Test. 26, 614–618 (2007).
[Crossref]

Salhi, M.

Sasaki, Y.

C. S. Otani, Y. Sasaki, H. Hoshina, M. Yamashita, G. Okazaki, and K. Kawase, “Development of a prototype apparatus for inspecting illicit drugs inside envelopes,” in Proceedings of the Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Terahertz Electronics, 2006 (IEEE, 2006), p. 173.
[Crossref]

Sawanaka, K.

Schabel, S.

Scheller, M.

C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg,M. Salhi, M. N. Krumbholz, C. Jördens, T. Hochrein, and M. Koch, “Terahertz imaging: applications and perspectives,” Appl. Opt. 49, E48–E57 (2010).
[Crossref] [PubMed]

M. Scheller, S. Wietzke, C. Jansen, and M. Koch, “Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory,” J. Phys. D 42, 065415(2009).
[Crossref]

M. Scheller, C. Jansen, and M. Koch, “Analyzing sub-100 μm samples with transmission terahertz time domain spectroscopy,” Opt. Commun. 282, 1304–1306 (2009).
[Crossref]

Scherger, B.

Sengupta, A.

A. Sengupta, A. Bandyopadhyay, B. F. Bowden, J. A. Harrington, and J. F. Federici, “Characterisation of olefin copolymers using terahertz spectroscopy,” Electron. Lett. 42, 1477–1479 (2006).
[Crossref]

Stuk, G.

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

Taday, P. F.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

ter Mors, M.

Thomson, M. D.

Towrie, M.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Tuennermann, A.

C. Brueckner, G. Notni, and A. Tuennermann, “Optimal arrangement of 90° off-axis parabolic mirrors in THz setups,” Optik (Jena) 121, 113–119 (2010).
[Crossref]

Van Der Weide, D.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

van Exeter, M.

Vieweg, N.

C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg,M. Salhi, M. N. Krumbholz, C. Jördens, T. Hochrein, and M. Koch, “Terahertz imaging: applications and perspectives,” Appl. Opt. 49, E48–E57 (2010).
[Crossref] [PubMed]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

von Spiegel, W.

Walther, M.

B. Fischer, M. Hoffmann, U. P. Jepsen, and M. Walther, “Use of the plastic materials topas and zeonex for biotechnological applications in the terahertz range,” European Patent Application EP1505382 (9 February 2005).

Watanabe, Y.

Wenckenbach, T.

White, J.

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

Wietzke, S.

C. Jansen, S. Wietzke, O. Peters, M. Scheller, N. Vieweg,M. Salhi, M. N. Krumbholz, C. Jördens, T. Hochrein, and M. Koch, “Terahertz imaging: applications and perspectives,” Appl. Opt. 49, E48–E57 (2010).
[Crossref] [PubMed]

C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
[Crossref]

M. Scheller, S. Wietzke, C. Jansen, and M. Koch, “Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory,” J. Phys. D 42, 065415(2009).
[Crossref]

S. Wietzke, C. Jansen, F. Rutza, D. M. Mittleman, and M. Koch, “Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy,” Polym. Test. 26, 614–618 (2007).
[Crossref]

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

Williamson, S.

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

Wood, K.

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Yamashita, M.

C. S. Otani, Y. Sasaki, H. Hoshina, M. Yamashita, G. Okazaki, and K. Kawase, “Development of a prototype apparatus for inspecting illicit drugs inside envelopes,” in Proceedings of the Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Terahertz Electronics, 2006 (IEEE, 2006), p. 173.
[Crossref]

Yasuda, T.

Yasui, T.

Yi, A. Y.

A. Y. Yi and A. Jain, “Compression molding of aspherical glass lenses—a combined experimental and numerical analysis,” J. Am. Ceram. Soc. 88, 579–586 (2005).
[Crossref]

Yu, D.-H.

Zhang, X.-C.

Zhao, G.

Zhao, H.

Zimdars, D.

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

Appl. Opt. (3)

Appl. Phys. Lett. (1)

C. Jansen, S. Wietzke, V. Astley, D. M. Mittleman, and M. Koch, “Mechanically flexible polymeric compound one-dimensional photonic crystals for terahertz frequencies,” Appl. Phys. Lett. 96, 111108 (2010).
[Crossref]

Electron. Lett. (1)

A. Sengupta, A. Bandyopadhyay, B. F. Bowden, J. A. Harrington, and J. F. Federici, “Characterisation of olefin copolymers using terahertz spectroscopy,” Electron. Lett. 42, 1477–1479 (2006).
[Crossref]

IEEE Trans. Instrum. Meas. (1)

S. O. Nelson, “Density-permittivity relationships for powdered and granular materials,” IEEE Trans. Instrum. Meas. 54, 2033–2040 (2005).
[Crossref]

Infrared Phys. (1)

J. R. Birch, “The far infrared optical constants of polyethylene,” Infrared Phys. 30, 195–197 (1990).
[Crossref]

Insight (1)

D. Zimdars, J. White, G. Stuk, A. Chernovsky, G. Fichter, and S. Williamson, “Large area terahertz imaging and non-destructive evaluation applications,” Insight 48, 537–539(2006).
[Crossref]

Int. J. Infrared Milli. Waves (1)

R. Piesiewicz, C. Jansen, S. Wietzke, D. Mittleman, M. Koch, and T. Kürner, “Properties of building and plastic materials in the THz range,” Int. J. Infrared Milli. Waves 28,363–371 (2007).
[Crossref]

J. Am. Ceram. Soc. (1)

A. Y. Yi and A. Jain, “Compression molding of aspherical glass lenses—a combined experimental and numerical analysis,” J. Am. Ceram. Soc. 88, 579–586 (2005).
[Crossref]

J. Korean Phys. Soc. (1)

Y. S. Jin, G. J. Kim, and S. G. Jeon, “Terahertz dielectric properties of polymers,” J. Korean Phys. Soc. 49, 513–517 (2006).
[Crossref]

J. Opt. Soc. Am. B (3)

J. Phys. D (1)

M. Scheller, S. Wietzke, C. Jansen, and M. Koch, “Modelling heterogeneous dielectric mixtures in the terahertz regime: a quasi-static effective medium theory,” J. Phys. D 42, 065415(2009).
[Crossref]

Laser Photon. Rev. (1)

P. U. Jepsen, D. G. Cooke, and M. Koch, “Terahertz spectroscopy and imaging—modern techniques and applications,” Laser Photon. Rev. 5, 124–166 (2010).
[Crossref]

Opt. Commun. (1)

M. Scheller, C. Jansen, and M. Koch, “Analyzing sub-100 μm samples with transmission terahertz time domain spectroscopy,” Opt. Commun. 282, 1304–1306 (2009).
[Crossref]

Opt. Eng. (1)

C. Jördens and M. Koch, “Detection of foreign bodies in chocolate with pulsed terahertz spectroscopy,” Opt. Eng. 47, 037003 (2008).
[Crossref]

Opt. Express (6)

Opt. Lett. (1)

Optik (Jena) (1)

C. Brueckner, G. Notni, and A. Tuennermann, “Optimal arrangement of 90° off-axis parabolic mirrors in THz setups,” Optik (Jena) 121, 113–119 (2010).
[Crossref]

Phil. Trans. R. Soc. A (1)

P. F. Taday, D. Van Der Weide, K. Wood, M. Chamberlain, H. Roskos, C. Phillips, D. Newnham, M. Towrie, and I. Appelquist, “Applications of terahertz spectroscopy to pharmaceutical sciences,” Phil. Trans. R. Soc. A 362, 351–364(2004).
[Crossref] [PubMed]

Polym. Test. (2)

S. Wietzke, C. Jansen, F. Rutza, D. M. Mittleman, and M. Koch, “Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy,” Polym. Test. 26, 614–618 (2007).
[Crossref]

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polym. Test. 28, 30–35 (2009).
[Crossref]

Polymer Testing (1)

N. Krumbholz, T. Hochrein, N. Vieweg, T. Hasek, K. Kretschmer, M. Bastian, M. Mikulics, and M. Koch, “Monitoring polymeric compounding processes inline with THz time-domain spectroscopy,” Polymer Testing 28, 30–35(2009).
[Crossref]

Proc. IEEE (1)

M. Naftaly and R. E. Miles, “Terahertz time-domain spectroscopy for material characterization,” Proc. IEEE 95, 1658–1665 (2007).
[Crossref]

Other (5)

W. R. Folks, S. K. Pandey, and G. Boreman, “Refractive index at THz frequencies of various plastics,” in Optical Terahertz Science and Technology, OSA Technical Digest Series (CD) (Optical Society of America, 2007), paper MD10.

C. Jo¨rdens, C. Jansen, and M. Koch, “Terahertz-Volumen-Bauelement,” German Patent Application 10 2008 030 127.A1.

www.lytera.com

B. Fischer, M. Hoffmann, U. P. Jepsen, and M. Walther, “Use of the plastic materials topas and zeonex for biotechnological applications in the terahertz range,” European Patent Application EP1505382 (9 February 2005).

C. S. Otani, Y. Sasaki, H. Hoshina, M. Yamashita, G. Okazaki, and K. Kawase, “Development of a prototype apparatus for inspecting illicit drugs inside envelopes,” in Proceedings of the Joint 31st International Conference on Infrared Millimeter Waves and 14th International Conference on Terahertz Electronics, 2006 (IEEE, 2006), p. 173.
[Crossref]

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Figures (5)

Fig. 1
Fig. 1

(a) Refractive index n and (b) absorption coefficient α for pellets pressed from micropowders Polyblend 100XF (HDPE/PTFE) and Propyltex 325s (PP) measured by THz TDS. In (a), the error bars give the 95% confidence interval at 1 THz on a zoomed-in scale. In (b), the confidence interval is indicated by the dashed curves.

Fig. 2
Fig. 2

Lens shape and path of rays obtained from ray-tracing software for a focal length of 60 mm and a refractive index of 1.45. f specifies the focal length, measured from the lens surface.

Fig. 3
Fig. 3

Photos showing (a) the hydraulic press and (b) the two lens molds. For compression molding the molds are inserted into a cylindric steel holder indicated by the arrow in (a). In (c), one of the fabricated CMLs in a ring holder is shown.

Fig. 4
Fig. 4

(a) Sagittal and (b) transversal THz beam profile for the HDPE/PTFE CML. In (c), a Gaussian fit of horizontal (x) and vertical (y) cuts across the normalized beam profile in (b) is shown.

Fig. 5
Fig. 5

(a) Sagittal and (b) transversal THz beam profile for the PP CML. In (c), a Gaussian fit of horizontal (x) and vertical (y) cuts across the normalized beam profile in (b) is shown.

Tables (2)

Tables Icon

Table 1 Physical Properties of the Micropowder Materials According to the Data Sheets

Tables Icon

Table 2 Measured Density ρ meas and Refractive Index n at 1 THz of the Used Micropowder Materials

Equations (1)

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I = | a | 2 d t ,

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