Pemanfaatan daun sereh (Cymbopogon citratus) dan lidah mertua (Sansevieria trifasciata) sebagai kisi difraksi sederhana berbantuan tracker

Abstrak. Gelombang cahaya yang mengalami pelenturan ketika melewati sebuah celah sempit disebut dengan fenomena difraksi. Fenomena difraksi dapat dilihat dengan melakukan eksperimen sederhana menggunakan bahan alam. Penelitian ini menggunakan kisi berbahan daun sereh (Cymbopogon citratus) dan tanaman lidah mertua (Sansevieria trifasciata) dengan menggunakan laser merah (λ = 632,8 nm) dengan beberapa variasi jarak kisi terhadap layar. Pola difraksi dianalisis menggunakan perangkat lunak Tracker. Hasil penelitian ini menunjukkan bahwa kisi difraksi menggunakan daun sereh dan lidah mertua menunjukkan fenomena difraksi cahaya sehingga dapat digunakan sebagai kisi difraksi sederhana berbahan alam dengan nilai d=(34.20 +/- 7.86) x 10^-6 m dan d=(62.50 +/- 13.60) x 10^-6 m pada kisi difraksi tanaman lidah mertua. Abstract. The light waves which flex when they pass through a narrow gap are called diffraction. The diffraction phenomenon can be seen by conducting simple experiments using natural materials. This study used a diffraction grating made from lemongrass leaves (Cymbopogon citratus) and sansevieria (Sansevieria trifasciata) using a red laser (λ = 632.8 nm) with several variations in the distance of the diffraction grating to the screen. The diffraction patterns were analyzed using Tracker software. The results of this study show that the diffraction grating using lemongrass leaves and sansevieria  show the phenomenon of light diffraction so that it can be used as a simple diffraction grating made from natural ingredients with values d=(34.20 +/- 7.86) x 10^-6 m of lemongrass leaves and d=(62.50 +/- 13.60) x 10^-6 m for the diffraction grating of the sansevieria

Differentiation Between Organic and Non-Organic Apples Using Diffraction Grating and Image Processing—A Cost-Effective Approach

As the expectation for higher quality of life increases, consumers have higher demands for quality food. Food authentication is the technical means of ensuring food is what it says it is. A popular approach to food authentication is based on spectroscopy, which has been widely used for identifying and quantifying the chemical components of an object. This approach is non-destructive and effective but expensive. This paper presents a computer vision-based sensor system for food authentication, i.e., differentiating organic from non-organic apples. This sensor system consists of low-cost hardware and pattern recognition software. We use a flashlight to illuminate apples and capture their images through a diffraction grating. These diffraction images are then converted into a data matrix for classification by pattern recognition algorithms, including k-nearest neighbors (k-NN), support vector machine (SVM) and three partial least squares discriminant analysis (PLS-DA)- based methods. We carry out experiments on a reasonable collection of apple samples and employ a proper pre-processing, resulting in a highest classification accuracy of 94%. Our studies conclude that this sensor system has the potential to provide a viable solution to empower consumers in food authentication