Quantitative Investigation of the Texture of a Hair Strand Using Single-Slit Diffraction
Quantitative Investigation of the Texture of a Hair Strand
using Single-Slit Diffraction
Stephen Flores1, Ailene Gonzales2
Department of Physics, University of San Carlos, Nasipit, Talamban, Cebu City 6000
1step.upflores@yahoo.com
2avg08_1s2 @yahoo.com
Abstract
This paper presents the utilization of the single slit-diffraction phenomena in analyzing the physical characteristics of a hair strand. Hair samples with various macroscopic textures were used as barriers to produce a diffraction pattern where the distance between fringes were readily obtained using a program that displays its line profile. The eccentricity values, [pic], are (0.12±0.01), (0.29±0.04), (0.33±0.01), (0.35±0.03) for Sample 1 to 4 respectively. Almost all of the samples exhibit eccentricities of less than 0.5 which means all of them are fairly straight. But in comparison, the eccentricities show that Samples 1 is a fairly straight hair while Samples 2, 3 and 4 are wavy hairs. These implications conform to the real macroscopic texture of each hair strand.
1. Introduction Hair strands, such as those of the animals and humans have been of particular interests in different fields since it offers variety of information. In forensic investigation for instance, a strand of hair is considered important evidence in pointing out the identity of whoever was in the crime scene. In fields such as this, the biological attributes of the human hair is analyzed for DNA identification. In this experiment, the physical characteristic of the human hair is quantitatively investigated using one of physics’ useful phenomena known as diffraction. This occurs when a wave such as light passes around an obstacle or through an opening. Aside from this study, diffraction has also been cleverly taken advantage of in applications such as x-ray diffraction of crystals and holography [1].
2. Theory According to Babinet’s principle, the diffraction pattern produced by a barrier is
using Single-Slit Diffraction
Stephen Flores1, Ailene Gonzales2
Department of Physics, University of San Carlos, Nasipit, Talamban, Cebu City 6000
1step.upflores@yahoo.com
2avg08_1s2 @yahoo.com
Abstract
This paper presents the utilization of the single slit-diffraction phenomena in analyzing the physical characteristics of a hair strand. Hair samples with various macroscopic textures were used as barriers to produce a diffraction pattern where the distance between fringes were readily obtained using a program that displays its line profile. The eccentricity values, [pic], are (0.12±0.01), (0.29±0.04), (0.33±0.01), (0.35±0.03) for Sample 1 to 4 respectively. Almost all of the samples exhibit eccentricities of less than 0.5 which means all of them are fairly straight. But in comparison, the eccentricities show that Samples 1 is a fairly straight hair while Samples 2, 3 and 4 are wavy hairs. These implications conform to the real macroscopic texture of each hair strand.
1. Introduction Hair strands, such as those of the animals and humans have been of particular interests in different fields since it offers variety of information. In forensic investigation for instance, a strand of hair is considered important evidence in pointing out the identity of whoever was in the crime scene. In fields such as this, the biological attributes of the human hair is analyzed for DNA identification. In this experiment, the physical characteristic of the human hair is quantitatively investigated using one of physics’ useful phenomena known as diffraction. This occurs when a wave such as light passes around an obstacle or through an opening. Aside from this study, diffraction has also been cleverly taken advantage of in applications such as x-ray diffraction of crystals and holography [1].
2. Theory According to Babinet’s principle, the diffraction pattern produced by a barrier is
References: Wesley, San Francisco, CA. 2008. 3. Y.Z Umol, “Babinet’s principle in the Fraunhoffer Diffraction by a Finite Thin Wire”, “Optik”, 2011. 4. G. Goth, “Measuring the Sizes of Biological Samples by Diffraction” “The Physics Teacher”, December, 1995.