Abstract

We report an angle-selective optical filter (ASOF) for highly sensitive reflection photoplethysmography (PPG) sensors. The ASOF features slanted aluminum (Al) micromirror arrays embedded in transparent polymer resin, which effectively block scattered light under human tissue. The device microfabrication was done by using geometry-guided resist reflow of polymer micropatterns, polydimethylsiloxane replica molding, and oblique angle deposition of thin Al film. The angular transmittance through the ASOF is precisely controlled by the angle of micromirrors. For the mirror angle of 30 degrees, the ASOF accepts an incident light between - 90 to + 50 degrees and the maximum transmittance at - 55 degrees. The ASOF exhibits the substantial reduction of both the in-band noise of PPG signals over a factor of two and the low-frequency noise by three times. Consequently, this filter allows distinguishing the diastolic peak that allows miscellaneous parameters with diverse vascular information. This optical filter provides a new opportunity for highly sensitive PPG monitoring or miscellaneous optical tomography.

© 2017 Optical Society of America

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References

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    [Crossref] [PubMed]
  3. M. Elgendi, “On the Analysis of Fingertip Photoplethysmogram Signals,” Curr. Cardiol. Rev. 8(1), 14–25 (2012).
    [Crossref] [PubMed]
  4. K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
    [Crossref] [PubMed]
  5. H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
    [Crossref] [PubMed]
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    [Crossref] [PubMed]
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    [Crossref] [PubMed]
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    [Crossref] [PubMed]
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    [Crossref] [PubMed]
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2016 (2)

C. Zhou, J. Feng, J. Hu, and X. Ye, “Study of Artifact-Resistive Technology Based on a Novel Dual Photoplethysmography Method for Wearable Pulse Rate Monitors,” J. Med. Syst. 40(3), 56 (2016).
[Crossref] [PubMed]

K. M. Warren, J. R. Harvey, K. H. Chon, and Y. Mendelson, “Improving Pulse Rate Measurements during Random Motion Using a Wearable Multichannel Reflectance Photoplethysmograph,” Sensors (Basel) 16(3), 342 (2016).
[Crossref] [PubMed]

2014 (3)

T. Tamura, Y. Maeda, M. Sekine, and M. Yoshida, “Wearable Photoplethysmographic Sensors-Past and Present,” Electronics (Basel) 3(2), 282–302 (2014).
[Crossref]

A. Bjorgan, M. Milanic, and L. L. Randeberg, “Estimation of Skin Optical Parameters for Real-time Hyperspectral Imaging Applications,” J. Biomed. Opt. 19(6), 066003 (2014).
[Crossref] [PubMed]

J.-J. Kim, S.-P. Yang, D. Keum, and K.-H. Jeong, “Asymmetric Optical Microstructures Driven by Geometry-guided Resist Reflow,” Opt. Express 22(18), 22089–22094 (2014).
[Crossref] [PubMed]

2012 (2)

M. R. Ram, K. V. Madhav, E. H. Krishna, N. R. Komalla, and K. A. Reddy, “A Novel Approach for Motion Artifact Reduction in PPG Signals Based on AS-LMS Adaptive Filter,” IEEE Trans. Instrum. Meas. 61(5), 1445–1457 (2012).
[Crossref]

M. Elgendi, “On the Analysis of Fingertip Photoplethysmogram Signals,” Curr. Cardiol. Rev. 8(1), 14–25 (2012).
[Crossref] [PubMed]

2011 (1)

F.-H. Huang, P.-J. Yuan, K.-P. Lin, H.-H. Chang, and C.-L. Tsai, “Analysis of Reflectance Photoplethysmograph Sensors,” World Acad. Sci. Eng. Technol. 5(11), 1266–1269 (2011).

2010 (2)

E. C.-P. Chua, S. J. Redmond, G. McDarby, and C. Heneghan, “Towards Using Photo-plethysmogram Amplitude to Measure Blood Pressure During Sleep,” Ann. Biomed. Eng. 38(3), 945–954 (2010).
[Crossref] [PubMed]

T. Durduran, R. Choe, W. B. Baker, and A. G. Yodh, “Diffuse Optics for Tissue Monitoring and Tomography,” Rep. Prog. Phys. 73(7), 076701 (2010).
[Crossref] [PubMed]

2008 (1)

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

2007 (2)

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

J. Allen, “Photoplethysmography and its application in clinical physiological measurement,” Physiol. Meas. 28(3), R1–R39 (2007).
[Crossref] [PubMed]

2003 (1)

H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
[Crossref] [PubMed]

2002 (1)

S. C. Millasseau, R. P. Kelly, J. M. Ritter, and P. J. Chowienczyk, “Determination of Age-related Increases in Large Artery Stiffness by Digital Pulse Contour Analysis,” Clin. Sci. 103(4), 371–377 (2002).
[Crossref] [PubMed]

2001 (1)

M. J. Hayes and P. R. Smith, “A New Method for Pulse Oximetry Possessing Inherent Insensitivity to Artifact,” IEEE Trans. Biomed. Eng. 48(4), 452–461 (2001).
[Crossref] [PubMed]

1999 (1)

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

1998 (1)

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

1996 (1)

W. B. Murray and P. A. Foster, “The Peripheral Pulse Wave: Information Overlooked,” J. Clin. Monit. 12(5), 365–377 (1996).
[Crossref] [PubMed]

1995 (1)

1985 (1)

J. C. Dorlas and J. A. Nijboer, “Photo-electric Plethysmography as a Monitoring Device in Anaesthesia. Application and interpretation,” Br. J. Anaesth. 57(5), 524–530 (1985).
[Crossref] [PubMed]

Aikawa, M.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

Allen, J.

J. Allen, “Photoplethysmography and its application in clinical physiological measurement,” Physiol. Meas. 28(3), R1–R39 (2007).
[Crossref] [PubMed]

Andersson, T. L. G.

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Andersson-Engels, S.

Anggård, E. E.

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Asada, H. H.

H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
[Crossref] [PubMed]

Awad, A. A.

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

Badr, T. M.

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

Baker, W. B.

T. Durduran, R. Choe, W. B. Baker, and A. G. Yodh, “Diffuse Optics for Tissue Monitoring and Tomography,” Rep. Prog. Phys. 73(7), 076701 (2010).
[Crossref] [PubMed]

Bjorgan, A.

A. Bjorgan, M. Milanic, and L. L. Randeberg, “Estimation of Skin Optical Parameters for Real-time Hyperspectral Imaging Applications,” J. Biomed. Opt. 19(6), 066003 (2014).
[Crossref] [PubMed]

Chang, H.-H.

F.-H. Huang, P.-J. Yuan, K.-P. Lin, H.-H. Chang, and C.-L. Tsai, “Analysis of Reflectance Photoplethysmograph Sensors,” World Acad. Sci. Eng. Technol. 5(11), 1266–1269 (2011).

Choe, R.

T. Durduran, R. Choe, W. B. Baker, and A. G. Yodh, “Diffuse Optics for Tissue Monitoring and Tomography,” Rep. Prog. Phys. 73(7), 076701 (2010).
[Crossref] [PubMed]

Chon, K. H.

K. M. Warren, J. R. Harvey, K. H. Chon, and Y. Mendelson, “Improving Pulse Rate Measurements during Random Motion Using a Wearable Multichannel Reflectance Photoplethysmograph,” Sensors (Basel) 16(3), 342 (2016).
[Crossref] [PubMed]

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

Chowienczyk, P. J.

S. C. Millasseau, R. P. Kelly, J. M. Ritter, and P. J. Chowienczyk, “Determination of Age-related Increases in Large Artery Stiffness by Digital Pulse Contour Analysis,” Clin. Sci. 103(4), 371–377 (2002).
[Crossref] [PubMed]

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Chua, E. C.-P.

E. C.-P. Chua, S. J. Redmond, G. McDarby, and C. Heneghan, “Towards Using Photo-plethysmogram Amplitude to Measure Blood Pressure During Sleep,” Ann. Biomed. Eng. 38(3), 945–954 (2010).
[Crossref] [PubMed]

Dorlas, J. C.

J. C. Dorlas and J. A. Nijboer, “Photo-electric Plethysmography as a Monitoring Device in Anaesthesia. Application and interpretation,” Br. J. Anaesth. 57(5), 524–530 (1985).
[Crossref] [PubMed]

Durduran, T.

T. Durduran, R. Choe, W. B. Baker, and A. G. Yodh, “Diffuse Optics for Tissue Monitoring and Tomography,” Rep. Prog. Phys. 73(7), 076701 (2010).
[Crossref] [PubMed]

Elgendi, M.

M. Elgendi, “On the Analysis of Fingertip Photoplethysmogram Signals,” Curr. Cardiol. Rev. 8(1), 14–25 (2012).
[Crossref] [PubMed]

Feng, J.

C. Zhou, J. Feng, J. Hu, and X. Ye, “Study of Artifact-Resistive Technology Based on a Novel Dual Photoplethysmography Method for Wearable Pulse Rate Monitors,” J. Med. Syst. 40(3), 56 (2016).
[Crossref] [PubMed]

Foster, P. A.

W. B. Murray and P. A. Foster, “The Peripheral Pulse Wave: Information Overlooked,” J. Clin. Monit. 12(5), 365–377 (1996).
[Crossref] [PubMed]

Fujita, M.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

Gosling, R. G.

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Haddadin, A. S.

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

Harvey, J. R.

K. M. Warren, J. R. Harvey, K. H. Chon, and Y. Mendelson, “Improving Pulse Rate Measurements during Random Motion Using a Wearable Multichannel Reflectance Photoplethysmograph,” Sensors (Basel) 16(3), 342 (2016).
[Crossref] [PubMed]

Hayes, M. J.

M. J. Hayes and P. R. Smith, “A New Method for Pulse Oximetry Possessing Inherent Insensitivity to Artifact,” IEEE Trans. Biomed. Eng. 48(4), 452–461 (2001).
[Crossref] [PubMed]

Heneghan, C.

E. C.-P. Chua, S. J. Redmond, G. McDarby, and C. Heneghan, “Towards Using Photo-plethysmogram Amplitude to Measure Blood Pressure During Sleep,” Ann. Biomed. Eng. 38(3), 945–954 (2010).
[Crossref] [PubMed]

Hu, J.

C. Zhou, J. Feng, J. Hu, and X. Ye, “Study of Artifact-Resistive Technology Based on a Novel Dual Photoplethysmography Method for Wearable Pulse Rate Monitors,” J. Med. Syst. 40(3), 56 (2016).
[Crossref] [PubMed]

Huang, F.-H.

F.-H. Huang, P.-J. Yuan, K.-P. Lin, H.-H. Chang, and C.-L. Tsai, “Analysis of Reflectance Photoplethysmograph Sensors,” World Acad. Sci. Eng. Technol. 5(11), 1266–1269 (2011).

Hutchinson, R. C.

H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
[Crossref] [PubMed]

Ibukiyama, C.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

Jeong, K.-H.

Ju, K.

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

Kelly, R. P.

S. C. Millasseau, R. P. Kelly, J. M. Ritter, and P. J. Chowienczyk, “Determination of Age-related Increases in Large Artery Stiffness by Digital Pulse Contour Analysis,” Clin. Sci. 103(4), 371–377 (2002).
[Crossref] [PubMed]

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Keum, D.

Kim, J.-J.

Komalla, N. R.

M. R. Ram, K. V. Madhav, E. H. Krishna, N. R. Komalla, and K. A. Reddy, “A Novel Approach for Motion Artifact Reduction in PPG Signals Based on AS-LMS Adaptive Filter,” IEEE Trans. Instrum. Meas. 61(5), 1445–1457 (2012).
[Crossref]

Krishna, E. H.

M. R. Ram, K. V. Madhav, E. H. Krishna, N. R. Komalla, and K. A. Reddy, “A Novel Approach for Motion Artifact Reduction in PPG Signals Based on AS-LMS Adaptive Filter,” IEEE Trans. Instrum. Meas. 61(5), 1445–1457 (2012).
[Crossref]

Lee, M.

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

Lin, K.-P.

F.-H. Huang, P.-J. Yuan, K.-P. Lin, H.-H. Chang, and C.-L. Tsai, “Analysis of Reflectance Photoplethysmograph Sensors,” World Acad. Sci. Eng. Technol. 5(11), 1266–1269 (2011).

Lu, S.

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

MacCallum, H.

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Madhav, K. V.

M. R. Ram, K. V. Madhav, E. H. Krishna, N. R. Komalla, and K. A. Reddy, “A Novel Approach for Motion Artifact Reduction in PPG Signals Based on AS-LMS Adaptive Filter,” IEEE Trans. Instrum. Meas. 61(5), 1445–1457 (2012).
[Crossref]

Maeda, Y.

T. Tamura, Y. Maeda, M. Sekine, and M. Yoshida, “Wearable Photoplethysmographic Sensors-Past and Present,” Electronics (Basel) 3(2), 282–302 (2014).
[Crossref]

Matsuoka, O.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

McDarby, G.

E. C.-P. Chua, S. J. Redmond, G. McDarby, and C. Heneghan, “Towards Using Photo-plethysmogram Amplitude to Measure Blood Pressure During Sleep,” Ann. Biomed. Eng. 38(3), 945–954 (2010).
[Crossref] [PubMed]

Mendelson, Y.

K. M. Warren, J. R. Harvey, K. H. Chon, and Y. Mendelson, “Improving Pulse Rate Measurements during Random Motion Using a Wearable Multichannel Reflectance Photoplethysmograph,” Sensors (Basel) 16(3), 342 (2016).
[Crossref] [PubMed]

Milanic, M.

A. Bjorgan, M. Milanic, and L. L. Randeberg, “Estimation of Skin Optical Parameters for Real-time Hyperspectral Imaging Applications,” J. Biomed. Opt. 19(6), 066003 (2014).
[Crossref] [PubMed]

Millasseau, S. C.

S. C. Millasseau, R. P. Kelly, J. M. Ritter, and P. J. Chowienczyk, “Determination of Age-related Increases in Large Artery Stiffness by Digital Pulse Contour Analysis,” Clin. Sci. 103(4), 371–377 (2002).
[Crossref] [PubMed]

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Murray, W. B.

W. B. Murray and P. A. Foster, “The Peripheral Pulse Wave: Information Overlooked,” J. Clin. Monit. 12(5), 365–377 (1996).
[Crossref] [PubMed]

Nijboer, J. A.

J. C. Dorlas and J. A. Nijboer, “Photo-electric Plethysmography as a Monitoring Device in Anaesthesia. Application and interpretation,” Br. J. Anaesth. 57(5), 524–530 (1985).
[Crossref] [PubMed]

Osei, E. K.

Patterson, M. S.

Ram, M. R.

M. R. Ram, K. V. Madhav, E. H. Krishna, N. R. Komalla, and K. A. Reddy, “A Novel Approach for Motion Artifact Reduction in PPG Signals Based on AS-LMS Adaptive Filter,” IEEE Trans. Instrum. Meas. 61(5), 1445–1457 (2012).
[Crossref]

Randeberg, L. L.

A. Bjorgan, M. Milanic, and L. L. Randeberg, “Estimation of Skin Optical Parameters for Real-time Hyperspectral Imaging Applications,” J. Biomed. Opt. 19(6), 066003 (2014).
[Crossref] [PubMed]

Reddy, K. A.

M. R. Ram, K. V. Madhav, E. H. Krishna, N. R. Komalla, and K. A. Reddy, “A Novel Approach for Motion Artifact Reduction in PPG Signals Based on AS-LMS Adaptive Filter,” IEEE Trans. Instrum. Meas. 61(5), 1445–1457 (2012).
[Crossref]

Redmond, S. J.

E. C.-P. Chua, S. J. Redmond, G. McDarby, and C. Heneghan, “Towards Using Photo-plethysmogram Amplitude to Measure Blood Pressure During Sleep,” Ann. Biomed. Eng. 38(3), 945–954 (2010).
[Crossref] [PubMed]

Reisner, A.

H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
[Crossref] [PubMed]

Rhee, S.

H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
[Crossref] [PubMed]

Ritter, J. M.

S. C. Millasseau, R. P. Kelly, J. M. Ritter, and P. J. Chowienczyk, “Determination of Age-related Increases in Large Artery Stiffness by Digital Pulse Contour Analysis,” Clin. Sci. 103(4), 371–377 (2002).
[Crossref] [PubMed]

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

Saiki, T.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

Sekine, M.

T. Tamura, Y. Maeda, M. Sekine, and M. Yoshida, “Wearable Photoplethysmographic Sensors-Past and Present,” Electronics (Basel) 3(2), 282–302 (2014).
[Crossref]

Shaltis, P.

H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
[Crossref] [PubMed]

Shelley, K.

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

Shelley, K. H.

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

Shin, K.

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

Silverman, D. G.

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

Smith, P. R.

M. J. Hayes and P. R. Smith, “A New Method for Pulse Oximetry Possessing Inherent Insensitivity to Artifact,” IEEE Trans. Biomed. Eng. 48(4), 452–461 (2001).
[Crossref] [PubMed]

Stout, R. G.

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

Takazawa, K.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

Tamura, S.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

Tamura, T.

T. Tamura, Y. Maeda, M. Sekine, and M. Yoshida, “Wearable Photoplethysmographic Sensors-Past and Present,” Electronics (Basel) 3(2), 282–302 (2014).
[Crossref]

Tanaka, N.

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

Tantawy, H.

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

Tsai, C.-L.

F.-H. Huang, P.-J. Yuan, K.-P. Lin, H.-H. Chang, and C.-L. Tsai, “Analysis of Reflectance Photoplethysmograph Sensors,” World Acad. Sci. Eng. Technol. 5(11), 1266–1269 (2011).

Warren, K. M.

K. M. Warren, J. R. Harvey, K. H. Chon, and Y. Mendelson, “Improving Pulse Rate Measurements during Random Motion Using a Wearable Multichannel Reflectance Photoplethysmograph,” Sensors (Basel) 16(3), 342 (2016).
[Crossref] [PubMed]

Wilson, B. C.

Yang, S.-P.

Ye, X.

C. Zhou, J. Feng, J. Hu, and X. Ye, “Study of Artifact-Resistive Technology Based on a Novel Dual Photoplethysmography Method for Wearable Pulse Rate Monitors,” J. Med. Syst. 40(3), 56 (2016).
[Crossref] [PubMed]

Yodh, A. G.

T. Durduran, R. Choe, W. B. Baker, and A. G. Yodh, “Diffuse Optics for Tissue Monitoring and Tomography,” Rep. Prog. Phys. 73(7), 076701 (2010).
[Crossref] [PubMed]

Yoshida, M.

T. Tamura, Y. Maeda, M. Sekine, and M. Yoshida, “Wearable Photoplethysmographic Sensors-Past and Present,” Electronics (Basel) 3(2), 282–302 (2014).
[Crossref]

Yuan, P.-J.

F.-H. Huang, P.-J. Yuan, K.-P. Lin, H.-H. Chang, and C.-L. Tsai, “Analysis of Reflectance Photoplethysmograph Sensors,” World Acad. Sci. Eng. Technol. 5(11), 1266–1269 (2011).

Zhao, H.

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

Zhou, C.

C. Zhou, J. Feng, J. Hu, and X. Ye, “Study of Artifact-Resistive Technology Based on a Novel Dual Photoplethysmography Method for Wearable Pulse Rate Monitors,” J. Med. Syst. 40(3), 56 (2016).
[Crossref] [PubMed]

Ann. Biomed. Eng. (1)

E. C.-P. Chua, S. J. Redmond, G. McDarby, and C. Heneghan, “Towards Using Photo-plethysmogram Amplitude to Measure Blood Pressure During Sleep,” Ann. Biomed. Eng. 38(3), 945–954 (2010).
[Crossref] [PubMed]

Appl. Opt. (1)

Br. J. Anaesth. (1)

J. C. Dorlas and J. A. Nijboer, “Photo-electric Plethysmography as a Monitoring Device in Anaesthesia. Application and interpretation,” Br. J. Anaesth. 57(5), 524–530 (1985).
[Crossref] [PubMed]

Clin. Sci. (1)

S. C. Millasseau, R. P. Kelly, J. M. Ritter, and P. J. Chowienczyk, “Determination of Age-related Increases in Large Artery Stiffness by Digital Pulse Contour Analysis,” Clin. Sci. 103(4), 371–377 (2002).
[Crossref] [PubMed]

Curr. Cardiol. Rev. (1)

M. Elgendi, “On the Analysis of Fingertip Photoplethysmogram Signals,” Curr. Cardiol. Rev. 8(1), 14–25 (2012).
[Crossref] [PubMed]

Electronics (Basel) (1)

T. Tamura, Y. Maeda, M. Sekine, and M. Yoshida, “Wearable Photoplethysmographic Sensors-Past and Present,” Electronics (Basel) 3(2), 282–302 (2014).
[Crossref]

Hypertension (1)

K. Takazawa, N. Tanaka, M. Fujita, O. Matsuoka, T. Saiki, M. Aikawa, S. Tamura, and C. Ibukiyama, “Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform,” Hypertension 32(2), 365–370 (1998).
[Crossref] [PubMed]

IEEE Eng. Med. Biol. Mag. (1)

H. H. Asada, P. Shaltis, A. Reisner, S. Rhee, and R. C. Hutchinson, “Mobile Monitoring with Wearable Photoplethysmographic Biosensors,” IEEE Eng. Med. Biol. Mag. 22(3), 28–40 (2003).
[Crossref] [PubMed]

IEEE Trans. Biomed. Eng. (1)

M. J. Hayes and P. R. Smith, “A New Method for Pulse Oximetry Possessing Inherent Insensitivity to Artifact,” IEEE Trans. Biomed. Eng. 48(4), 452–461 (2001).
[Crossref] [PubMed]

IEEE Trans. Instrum. Meas. (1)

M. R. Ram, K. V. Madhav, E. H. Krishna, N. R. Komalla, and K. A. Reddy, “A Novel Approach for Motion Artifact Reduction in PPG Signals Based on AS-LMS Adaptive Filter,” IEEE Trans. Instrum. Meas. 61(5), 1445–1457 (2012).
[Crossref]

J. Am. Coll. Cardiol. (1)

P. J. Chowienczyk, R. P. Kelly, H. MacCallum, S. C. Millasseau, T. L. G. Andersson, R. G. Gosling, J. M. Ritter, and E. E. Anggård, “Photoplethysmographic Assessment of Pulse Wave Reflection: blunted response to endothelium-dependent beta2-adrenergic vasodilation in type II diabetes mellitus,” J. Am. Coll. Cardiol. 34(7), 2007–2014 (1999).
[Crossref] [PubMed]

J. Biomed. Opt. (1)

A. Bjorgan, M. Milanic, and L. L. Randeberg, “Estimation of Skin Optical Parameters for Real-time Hyperspectral Imaging Applications,” J. Biomed. Opt. 19(6), 066003 (2014).
[Crossref] [PubMed]

J. Clin. Monit. (1)

W. B. Murray and P. A. Foster, “The Peripheral Pulse Wave: Information Overlooked,” J. Clin. Monit. 12(5), 365–377 (1996).
[Crossref] [PubMed]

J. Clin. Monit. Comput. (2)

S. Lu, H. Zhao, K. Ju, K. Shin, M. Lee, K. Shelley, and K. H. Chon, “Can Photoplethysmography Variability Serve as an Alternative Approach to Obtain Heart Rate Variability Information?” J. Clin. Monit. Comput. 22(1), 23–29 (2008).
[Crossref] [PubMed]

A. A. Awad, A. S. Haddadin, H. Tantawy, T. M. Badr, R. G. Stout, D. G. Silverman, and K. H. Shelley, “The Relationship Between the Photoplethysmographic Waveform and Systemic Vascular Resistance,” J. Clin. Monit. Comput. 21(6), 365–372 (2007).
[Crossref] [PubMed]

J. Med. Syst. (1)

C. Zhou, J. Feng, J. Hu, and X. Ye, “Study of Artifact-Resistive Technology Based on a Novel Dual Photoplethysmography Method for Wearable Pulse Rate Monitors,” J. Med. Syst. 40(3), 56 (2016).
[Crossref] [PubMed]

Opt. Express (1)

Physiol. Meas. (1)

J. Allen, “Photoplethysmography and its application in clinical physiological measurement,” Physiol. Meas. 28(3), R1–R39 (2007).
[Crossref] [PubMed]

Rep. Prog. Phys. (1)

T. Durduran, R. Choe, W. B. Baker, and A. G. Yodh, “Diffuse Optics for Tissue Monitoring and Tomography,” Rep. Prog. Phys. 73(7), 076701 (2010).
[Crossref] [PubMed]

Sensors (Basel) (1)

K. M. Warren, J. R. Harvey, K. H. Chon, and Y. Mendelson, “Improving Pulse Rate Measurements during Random Motion Using a Wearable Multichannel Reflectance Photoplethysmograph,” Sensors (Basel) 16(3), 342 (2016).
[Crossref] [PubMed]

World Acad. Sci. Eng. Technol. (1)

F.-H. Huang, P.-J. Yuan, K.-P. Lin, H.-H. Chang, and C.-L. Tsai, “Analysis of Reflectance Photoplethysmograph Sensors,” World Acad. Sci. Eng. Technol. 5(11), 1266–1269 (2011).

Other (1)

W. Fleming and D. P. Wesfall, “Adaptive Supersensitivity,” in Handbook of Experimental Pharmacology: Catecholamines I, U. Trendelenburg, and N. Weiner ed. (Springer, 1988).

Supplementary Material (1)

NameDescription
» Visualization 1       ASOF rotating in front of "KAIST" text printed on white paper.

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Figures (4)

Fig. 1
Fig. 1

Angle-selective optical filter (ASOF) for highly sensitive PPG sensors. (a) A schematic diagram of “banana” light shape under the human tissue. The red arrow is the light path followed by the Snell’s law which has a PPG signal. The green arrow is the highly scattered light losing their directionality. The incident angle of light is distributed from 0 degree to LED’s emitting angle. The incident light except these angle act as the noise of the PPG signals, which has low intensity and less information for vascular activity. (b) The cross-section of ASOF to calculate the transmittance, i.e., a ratio between the incident light and transmitted light area. The sum of l and Li is the incident light area and 2l is a transmitted light area. (c) The transmittance according to the filter angle when the incident angle of light is 0 degree. According to this result, the transmittance is set to half the maximum for the filter angle of 30 degrees. (d) Transmittance for the filter angle of 30 degrees depending on the incident angle. Both the theoretical and calculated results are in good agreement.

Fig. 2
Fig. 2

(a) Microfabrication procedure of the ASOF. SU-8 line patterns as a thermoset post were initially patterned on a Si wafer. The slanted microstructures with a target filter angle were then formed on the Si wafer by using the geometry-guided resist reflow method. The microstructures were transferred onto UV curable resin on a cover glass by using the PDMS replica and then A 500nm thick Al film was thermally evaporated on the replicated slanted microstructures. The slanted micromirrors were finally embedded in UV resin. (b) The perspective and (c) cross-sectional SEM images of slanted microstructures. The slanted microstructures are 10 μm in height and 17 μm in length and therefore they provide the filter angle of 30 degrees after the Al evaporation. (d) A perspective SEM image of the Al micromirror after focused ion-beam cut. Note that the side walls of the micromirrors are not covered with thin Al film and therefore still transparent after the embedment of micromirrors with additional UV resin.

Fig. 3
Fig. 3

(a) Light transmittance through the ASOF depending on an incident angle of 533 nm laser beam. The angular transmittance was measured with an integrating sphere rotating with respect to the ASOF. The experiment results are in good agreement with the calculated and theoretical results. However, the transmittance of ASOF shows a significant difference more than an incident angle of 50 degrees due to the optical diffraction from the Al micromirror arrays. (b) A transmitted image captured via ASOF rotating in front of “KAIST” text printed on white paper (see Visualization 1). (c) A schematic diagram of ASOF based PPG sensor. The ASOF on the PD was simply replaced with a glass window for the comparison between PPG sensors with and without the ASOF. (d) An optical image of a fully packaged PPG sensor consisting of PD, LED, RP and PCB.

Fig. 4
Fig. 4

(a) PPG signals after passing a bandpass filter of 0.5 Hz to 4 Hz. ASOF has little effect on the peak-to-peak value of the PPG signals. (b) Comparison of the experimental and the numerical results for peak-to-peak signals and DC noise of PPG signals. In both cases, ASOF clearly reduces DC noise by more than three times. (c) Ensemble averaged PPG signals. ASOF clearly indicates the diastolic peaks of PPG signals. The variation of the PPG signals, indicated by the error signals, indicates the in-band noise of the PPG signals, i.e. the sum of error signals. (d) In-band noise of PPG signals. ASOF reduces the in-band noise by twice. (e) Signal-to-noise ratio (SNR), defined as ratio of the power spectral density (PSD) of PPG signal and PSD of the noise in raw data. PSDSignal is the PSD of the PPG signal, and PSD of noise such as PSDHigh and PSDLow are the PSD of the higher and lower frequency noise than PPG signal, respectively. The SNR of the PPG signal is defined as the ratio between PSDSignal and the PSD of the noise, such as PSDHigh and PSDLow. According to this definition, ASOF improves SNR more than three times.

Equations (2)

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T={ 0, l<0 2l L i +l F, 0l< L i F, L i l ,
F=1 1 2 ( | n 1 cos θ i n 2 1 ( n 1 n 2 sin θ i ) 2 n 1 cos θ i + n 2 1 ( n 1 n 2 sin θ i ) 2 | 2 + | n 1 1 ( n 1 n 2 sin θ i ) 2 n 2 cos θ i n 1 1 ( n 1 n 2 sin θ i ) 2 + n 2 cos θ i | 2 ).

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