Abstract

This paper describes an attempt to develop a new NIR spectrometer to sort fruits according to the sugar content in the conditioning stations. This spectrometer, ranging from 800 to 1050 nm, is based on diode array technology. It is coupled with fiber optics, which allow multiplexing; 20 fibers have been detected by the camera, showing the potential multiplexing of 20 different points. The acquisition time is 40 ms per image (i.e., 2 ms per spectrum). A good signal-to-noise ratio has been recorded in the 820-1010 nm range. This spectrometer has been tested with a set of 79 peaches. Partial least-squares processing is applied to different wavelength ranges. The best coefficient of correlation, achieved with a reduced wavelength range (from 847 to 977 nm), is 0.81, and the standard error of prediction is 1.04°Brix. With this calibration, the fruits can be sorted into three maturity classes with a reliability of 76%. This performance, as well as the other characteristics of the instrument, is in accordance with the requirements of the conditioning station managers.

FR4-based electromagnetic scanning micro-grating integrated with an angle sensor for a low-cost NIR micro-spectrometer

Quan Wen, Hongjie Lei, Jian Huang, Fan Yu, Liangkun Huang, Jing Zhang, Dongling Li, Yingchun Peng, and Zhiyu Wen
Appl. Opt. 58(17) 4642-4646 (2019)

Nondestructive quantification of chemical and physical properties of fruits by time-resolved reflectance spectroscopy in the wavelength range 650–1000 nm

Rinaldo Cubeddu, Cosimo D’Andrea, Antonio Pifferi, Paola Taroni, Alessandro Torricelli, Gianluca Valentini, Colin Dover, David Johnson, Margarita Ruiz-Altisent, and Constantino Valero
Appl. Opt. 40(4) 538-543 (2001)

Biocompatible spider silk-based metal-dielectric fiber optic sugar sensor

Hsuan-Pei E, Jelene Antonicole Ngan Kong, Wei-Chun Chen, Che-Chin Chen, Chia-Hsiung Cheng, and Cheng-Yang Liu
Biomed. Opt. Express 13(9) 4483-4493 (2022)

Nano-strain resolution fiber-optic Fabry-Perot sensors compatible with moderate/low resolution VIS-NIR spectrometers

Simon Pevec and Denis Donlagic
Opt. Express 30(23) 41999-42014 (2022)

Low-cost 3D printed 1  nm resolution smartphone sensor-based spectrometer: instrument design and application in ultraviolet spectroscopy

Thomas C. Wilkes, Andrew J. S. McGonigle, Jon R. Willmott, Tom D. Pering, and Joseph M. Cook
Opt. Lett. 42(21) 4323-4326 (2017)