ANALYSIS ON THE PERFORMANCE OF LED AND LASER DIODE WITH CHARGE COUPLED DEVICE (CCD) LINEAR SENSOR MEASURING DIAMETER OF OBJECT

Abstract

Simple experiment measuring diameter of a solid object (coin) using LED and laser diode with Charge Coupled Device (CCD) linear sensor was conducted in this early stage study. Mostly, CCD and laser diode system are higher in cost because CCD used in industries equipped with an anti blooming protection system to protect the CCD pixel from receiving too high laser light intensities. Low cost atomic laser (Helium: Neon 10:1) with simple modification on light propagation is introduced. Combination of fan beam and parallel beam projection helps to reduce light intensities and expand laser light coverage area. Statistical analyses based on dot plot graph, Anderson Darling test and T-test were applied to choose the best transmitter for Charge Coupled Device (CCD) sensor. Based on T-test results with 95% confidence interval, low intensity laser diode for 5 and 10 cent diameter measurement gave P-value greater than 0.05, accepts laser as the best transmitter compared to LED. Single sensor data for LED and laser used for image reconstruction as an additional approach to prove the above result.