Mode-Field-Diameter and the Coupling Loss between Inner and Outer Segment of Photoreceptors


The characteristics of optical waveguide of human photoreceptors play important roles in vision. The mode-field-diameter (MFD) is a very important parameter of a single-mode waveguide, and it is related to many important optical characteristics of a single-mode waveguide. Here we show that MFDs of outer segments of human foveal cones are close to the minimum values at their geometric diameter for outer segments of foveal cones. Small MFD of outer segment is important for eyes to have high spatial resolution and low interaction between neighboring cones. We propose that the ellipsoids of foveal cones act as spot size converters to reduce the coupling losses between myoids and outer segments.

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Liang, A. , Hu, L. and Liang, Z. (2015) Mode-Field-Diameter and the Coupling Loss between Inner and Outer Segment of Photoreceptors. Optics and Photonics Journal, 5, 151-160. doi: 10.4236/opj.2015.54014.

Conflicts of Interest

The authors declare no conflicts of interest.


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