Light scattering patch device and preparation method thereof

A light scattering patch device, comprising a patch, an air gap, and a tapered optical fiber;

• wherein the patch is a transparent patch;
• wherein a refractive index of the patch is greater than a refractive index of a biological tissue;
• wherein a tip, a tapered transition zone and a partial unstretched zone of the tapered optical fiber are embedded in the patch, and the air gap is formed between the tip and the tapered transition zone of the tapered optical fiber and the patch;
• wherein a relationship between a cross-sectional radius F(z) of the tapered optical fiber and a distance z from a cross-section to the tip of the tapered optical fiber satisfies a function 1;
• assuming that a length of the tapered transition zone is d, and the function 1 is:
• F(z)=62.3−56.36×exp(−((135.8×(z/d)+16.18)/65.81){circumflex over ( )}2)+0.6324×exp(−((135.8×(z/d)+0.5469)/0.1508){circumflex over ( )}2)+1.103×exp(−((135.8×(z/d)+24.78)/−0.02043){circumflex over ( )}2)−12.1×exp(−((135.8×(z/d)−13.07)/−22.32){circumflex over ( )}2);
• and
• wherein the cross-sectional radius F(z), the distance z from the cross-section to the tip of the tapered optical fiber, and the length d of the tapered transition zone are all in the unit of μm.