[2] https://www.masimo.com

[3] https://www.orsense.com

[4] A Rani, V Singh, J Yadav et al. Biomedical Signal Processing and Control, 18, 214(2015).

[5] J Jiang, J Liu, C Zhu et al. Biomedical Optics Express, 9, 5903(2018).

[6] J Bigio I, A Jack D, R Mourant J et al. Applied Optics, 36, 5655(1997).

[7] H Liu. Applied Optics, 40, 1742(2001).

[8] G Durinck, S Leyre, Y Meuret et al. Applied Optics, 53, 2117(2014).

[9] M Chiarelli A, K A Low, E L Maclin. Photonics, 6, 79(2019).

[10] M Chiarelli A, A Low K, L Maclin E et al. Neurophotonics, 4, 021103(2017).

[11] T Han, J Jiang, J Liu et al. Biomedical Optics Express, 10, 4839(2019).

[13] T Han, J Liu, X Liu et al. SPIE Conference, Optical Diagnostics and Sensing XIX: Toward Point-of--Care Diagnostics(2019).

[14] J Farrell T, S Patterson M, B Wilson. Medical Physics, 19, 879(1992).

[15] B Fu, R Liu, X Min et al. Optics and Laser Technology, 91, 7(2017).

[16] M Cope, M Essenpreis, M Kohl et al. Optics Letters, 19, 2170(1994).