Light Sensor Of Smartphone Research Articles

Using Different Smartphone Sensors to Find the Speed of a Toy Car

There are many examples of using smartphones in physics experiments. Students and teachers can easily perform many physics experiments with the help of smartphone sensors, even experiments for which high-cost materials are needed. There are different types of such experiments in which various kinds of sensors are used. Many physical quantities can be reliably measured with smartphone sensors after some calibration. One of the physical quantities that can be determined with these sensors is object speed. For example, the angular velocities of rotating objects have been measured with a smartphone light as well as proximity, acceleration, and magnetic field sensors. The speeds of light-emitting objects traveling on a straight path and inclined plane have also been determined with a smartphone light sensor. Ball velocities have also been determined with a smartphone oscilloscope app. In this study, we determine the speed of a toy car over a certain distance using smartphone magnetic field, light, and proximity sensors simultaneously with just one experiment.

Multifunctional 3D-printed platform integrated with a smartphone ambient light sensor for halocarbon contaminants monitoring

3D-printed platforms integrated with smartphone light sensors have become a powerful tool for the development of frugal and facile biosensing systems. Herein, we report a 3D-printed platform for multimodal analysis (3D-PMA) based on a smartphone ambient light sensor (ALS). The proposed approach was first validated using a microtiter plate reader, and then its application potential was demonstrated by measuring halohydrin dehalogenase activities employing three different sample modes, viz . using enzyme-linked immunosorbent assay (ELISA) plate strips, cuvettes, and the glass fiber membrane as sample containers. For real-sample analysis, 1,3-dichloro-2-propanol (1,3-DCP), a toxic halogenated compound, was successfully detected in spiked river water samples with recoveries in the range of 101.95–109.70%. After demonstrating the suitability for liquid-phase assays, the 3D-PMA was also optimized for 1,3-DCP detection using a glass fiber membrane. The detection could be done using a 10 μ L reaction system with an assay time of 2 min. The assay showed two linear ranges. The calibration equation of Y = 81.687x + 140.060 was obtained from the lower part of the calibration curve and was used to calculate the detection limit of the system. Under optimized conditions, a detection limit of 80 μ M was achieved for 1,3-DCP. The small size of the device endows it with great promise for use as a benchtop and an on-demand detection system. The proposed low-cost and portable system has great potential for the (bio) sensing of different biological and environmental samples where biocomponent-analyte interaction leads to a color change of the reaction system, indicating its applicability in resource-constrained settings. • A smartphone assisted portable system was developed for environmental contaminants monitoring. • 3D-printed platform demonstrated potential utility for multimodal analysis. • Smartphone Ambient Light Sensor as a potential transducer for halocarbon detection.

Quantitative experiments in a distance lab: studying blackbody radiation with a smartphone

In this paper we present an experiment aimed at investigating the thermal radiation law. The spectrum of a filament light bulb is acquired at different temperatures using a low-cost grating spectrometer based on a smartphone camera, while the measurement of filament temperature is obtained indirectly from the temperature dependence of the filament resistance. Two different methods for measuring the light intensity are tested: one is based on the use of the ambient light sensor of a smartphone, the other on a home-made grating spectrometer coupled with the smartphone camera. We observe a good agreement of the experimental data with the theoretical predictions of the Planck distribution in the limit of the Wien approximation restricted to the wavelength range characterizing the response of the smartphone light sensor and camera.

Using smartphone cameras and ambient light sensors in distance learning: the attenuation law as experimental determination of gamma correction

In times of the explosion of distance learning, because of emergency due to the pandemic, smartphone sensors and cameras are extremely valuable for teachers as they allow students to perform significant experimental activities in their own homes. The open-source software Tracker can be used in combination with the smartphone camera to perform measurements not only of mechanics activities, but also of optics. In the latter case, it is not always easy for students to understand how the pixel brightness which can be inferred from the taken photos are related to actual physical light intensity. In this paper we present a simple experiment to verify the exponential decay in the intensity of light going through successive sheets of a material (the Lambert law) with two different methods, i.e. using either the smartphone light sensor or the smartphone camera and Tracker. Besides its theoretical significance, the experiment constitutes a useful tool for calibrating the camera/Tracker combination to use it for different experiments.

A paper based colorimeter using smartphone light sensor

A paper-based colorimeter for absorbance and concentration measurement of the food colouring dye is proposed. The paper-based colorimeter system consists of a white LED as light source, paper-based cuvette holder, and smartphone light sensor. The paper-based colorimeter with smartphone light sensor is low-cost, mobile and real-time for the detection of colouring dye concentration. The detection response of the paper-based colorimeter system was found to be linear with the colouring dye concentration in the range from 0 to 0.025 g/mL with a correlation coefficient (R2) 0.89±0.04. The experimental results show that this paper-based colorimeter system is highly sensitive and have a potential application, from student labs to small industries.

A smartphone-based multi-wavelength photometer for on-site detection of the liquid colorimetric assays for clinical biochemical analyses

A novel portable and cost-effective multi-wavelength smartphone colorimetric reader (MW-SCR) was designed for the quantitation of liquid colorimetric assays. Six light-emitting diodes (LEDs) with different wavelengths were assembled in a roulette fashion to form the light detection source. An ambient light sensor of smartphone was applied as the detector. Using this MW-SCR, we detected six common serum analytes, including alkaline phosphatase(ALP), potassium(K+), chloride(Cl−), alanine aminotransaminase(ALT), glycated serum protein(GSP), and albumin, to evaluate the feasibility and reliability of the MW-SCR. Strong linear regression (R2>0.99) analysis with a wide linear range and good limits of detection were found for this device, detection limits as low as 0.37 U/L, 0.0083 mmol/L, 0.78 mmol/L, 4.49 KarU, 0.023 mmol/L and 2.23 g/L for ALP, K+,Cl−, ALT, GSP and albumin, respectively, were achieved. It also had high repeatability that ranged from 0.20 to 0.61 % relative standard deviations (RSD), and the precision ranged of MW-SCR were from 0.26 to 1.17 % RSDs. Results demonstrated that our device showed remarkable stability, accuracy, and repeatability, presenting excellent consistency with a professional microplate reader. It can be redesigned for multiple indications, such as clinical biochemical analyses, food safety testing, environmental monitoring and so on, because it is open source, user friendly and easy manufacturing.

Utilization of Smartphone Light Sensors as Light Transmission Analyzer During the Obtaining of Polymeric Phase Inversion Membranes

Smartphone sensors are gaining research interest due to continuous sensor upgrades, leading to more precise readings of these sensors. For this study, the light sensor of a smartphone was used in determining light transmittance during the phase inversion process of ultrafiltration polysulfone - membrane manufacturing. Membrane separation is one of the best available technologies when it comes to water and wastewater treatment. The purpose of this study was to correlate light transmit tance, at certain demixing steps during phase inversion, with membrane porosity, pure water flux and cross - sectional SEM images. Results show close relation between light transmittance and the mentioned membrane properties.

Utilising Smartphone Light Sensors to Measure Egg White Ovalbumin Concentration in Eggs Collected from Yinchuan City, China

Cost-effective, portable, and rapid smartphone sensors will play a critical role in bringing chemical detection technologies from central laboratories to simple laboratories, such as those of schools in less-developed area. In this work, we study whether eggs in Yinchuan have a higher concentration of ovalbumin than that in ordinary eggs. We summarise previous research on sensors built inside smartphones, as well as some developments in the current literature, and develop a simple experimental procedure that utilises the light sensor of a smartphone to analyse light intensity and thereby determine the ovalbumin content of egg white cheaply and quickly. Most of the materials required for conducting this experiment can be easily found in simple school laboratories, and it allows solution concentrations to be quickly assessed by high school students in the data collection and analysis phase. Indeed, the data collected using smartphone light sensors were similar to those obtained using a spectrometer. It was concluded that egg white ovalbumin concentration in eggs collected from Yinchuan is higher than that in ordinary eggs.

Light Intensity Analysis Using Smartphone’s Light Sensor

Light is a form of electromagnetic energy radiation emitted in the visible part of the spectrum. This study was aimed to analyze the intensity of dynamic train light that moves constantly on a linear track using a smartphone light sensor. The method used in this research was the experimental method. The light sensor application used is available freely in the Physics Toolbox Suite on the smartphone. Experimental equipment was built using linear tracks, dynamic trains, flash light and lamp. Light sensor output produces luminosity (Ev) value versus time (s). The experimental results show that the light intensity at 3 volts with a distance of 5, 10, and 15 cm are 100, 250 and 300 cd, respectively. Whereas the intensity of light at 4.5 volts, the intensity of the light at distances of 5, 10, and 20 cm are 800 cd, 950 cd and 1200 cd, respectively. It is expected that the use of smartphones can increase students’ interest in learning physics concepts.

A simple pendulum-based measurement of g with a smartphone light sensor

A quick and very accessible method for the measurement of acceleration due to gravity is presented. The experimental set-up employs a smartphone ambient light sensor as the motion timer for measuring the period of a simple pendulum. This allowed us to obtain an experimental value, 9.72 + 0.05 m s−2, for the gravitational acceleration which is in good agreement with the local theoretical value of 9.78 m s−2.

A dynamic-based measurement of a spring constant with a smartphone light sensor

An accessible smartphone-based experimental set-up for measuring a spring constant is presented. Using the smartphone ambient light sensor as the motion timer that allows for the measurement of the period of oscillations of a vertical spring-mass oscillator we found the spring constant to be 27.3 0.2 N m−1. This measurement is in a satisfactory agreement with another experimental value, 26.7 0.1 N m−1, obtained via the traditional static method.

Preliminary study of simple methods to get the average speed using a smartphone's light sensor

This paper reports on the result of a preliminary study of utilization of a smartphone ambient light sensor for get the average speeds of motion along a straight line based on experiments. We attach a smartphone to a dynamics train that travels across multiple light sources where the distance is already set. The main source of this experiment is obtained from the luminosity curve obtained from free android applications. From the curve, we can get position information against time. So from the data we can get the value of average speed. Then the use of the smartphone light sensor in physics experiments can be done easily and fun.

Calculating the areas of polygons with a smartphone light sensor

ABSTRACTThis study explores finding the areas of polygons with a smartphone light sensor. A square and an irregular pentagon were chosen as our polygons. During the activity, the LED light was placed at the vertices of our polygons, and the illuminance values of this LED light were detected by the smartphone light sensor. The smartphone was placed on a rotating time-lapse device, and this device was placed at the intersection point of the line segments in the polygons. These line segments were also connected to the vertices of these polygons; therefore, the square was composed of four triangles and the pentagon of five triangles. While the rotating time-lapse device was rotating around itself, it captured the maximum illuminance values of the LED light. Using these maximum illuminance values, we calculated the lengths of the line segments. In addition, we knew the period of the rotating time-lapse device and the duration elapsed between two consecutive maximum illuminance values. Thus, we could calculate the angle between two consecutive line segments. With these values, we could also calculate the areas of the triangles in the polygons. Then, the areas of these triangles were summed to obtain the areas of the square and pentagon.

Finding the acceleration and speed of a light-emitting object on an inclined plane with a smartphone light sensor

This study investigates how the acceleration and speed of a light-emitting object on an inclined plane may be determined using a smartphone’s light sensor. A light-emitting object was released from the top of an inclined plane and its illuminance values were detected by a smartphone’s light sensor during its subsequent motion down the plane. Using the illuminance and time values recorded by the smartphone, the distances between the sensor and the light-emitting object can be calculated. From these known distance and time values, the uniform acceleration and speed of the light-emitting object at any time could also be determined. A second method was also used to determine these values, i.e. the analysis of video-recordings of the light-emitting object during its motion. The values found by these two different methods were in good agreement. Thus, this experiment demonstrates that a smartphone’s light sensor can be used as a reliable instrument to determine the constant acceleration and speed of light-emitting objects.

Finding the average speed of a light-emitting toy car with a smartphone light sensor

This study aims to demonstrate how the average speed of a light-emitting toy car may be determined using a smartphone’s light sensor. The freely available Android smartphone application, ‘AndroSensor’, was used for the experiment. The classroom experiment combines complementary physics knowledge of optics and kinematics to find the average speed of a moving object. The speed of the toy car is found by determining the distance between the light-emitting toy car and the smartphone, and the time taken to travel these distances. To ensure that the average speed of the toy car calculated with the help of the AndroSensor was correct, the average speed was also calculated by analyzing video-recordings of the toy car. The resulting speeds found with these different methods were in good agreement with each other. Hence, it can be concluded that reliable measurements of the average speed of light-emitting objects can be determined with the help of the light sensor of an Android smartphone.

Experimental demonstration of light sensor-based visible light communications using time shift light intensity modulation

An experimental light sensor-based indoor visible light communication (VLC) is presented. Light-emitting diodes (LEDs) primarily used for illumination are employed to transmit wireless optical data over a short distance, while a smartphone’s light sensor is used to receive the data. The light sensor in a smartphone is originally installed to function as a power saving method by adjusting the brightness of the smartphone screen. We propose an efficient and easy-to-use short range VLC based on this light sensor. To compensate for the inherent low sampling rate of the light sensor and also to avoid LED (transmitter) flickering, we propose time shift light intensity modulation. To verify the proposed light sensor VLC, experiments were conducted. The results demonstrate that the data can reliably be transmitted over the VLC link between the LEDs and the smartphone light sensor.