Developing Tools for Undergraduate Spectroscopy: An Inexpensive Visible Light Spectrometer

Abstract

The design and implementation of an inexpensive, high-resolution Littrow-type visible light spectrometer is presented. The instrument is built from low-cost materials and interfaced with the program RSpec for real-time spectral analysis, making it useful for classroom and laboratory exercises. Using a diffraction grating ruled at 1200 lines/mm and blazed in the first order, the spectrometer was found to have a resolution (R = λ/Δλ) of 7500 (0.07 nm) at 525 nm allowing for detailed spectroscopic experiments such as an analysis of the iodine vibronic spectrum or multiplet line splitting in the solar spectrum. The simple design of the spectrometer makes it possible to exchange gratings of different lines/mm easily. The instrument provides a means of incorporating macroscopic experimental observations of visible spectroscopy into the undergraduate chemistry program in a practical hands-on way while avoiding the “black-box” nature of many modern spectrometers. Special attention is given to the possibilities such an instrument presents for the introductory chemistry curriculum and example demonstrations and experiments are provided.

Studi Pengaruh Konsentrasi Larutan MnCl2 Terhadap Intensitas Citra Spektrometer Keping VCD

“…Saat ini, masih dibutuhkan suatu teknik spektroskopi sederhana sebagai alternative ketika alat-alat spektrometer modern tidak tersedia [4]. Spektroskopi sederhana dapat dibangun dengan menggunakan keping compact disc (CD) maupun digital versatile disks (DVD) karena keduanya memiliki kisikisi yang sangat rapat.…”

“…Pelemahan intensitas terepresentasi dengan nilai gradient garis sebesar -0.0242 yang menurut persamaan (2) adalah sebagai nilai B. Sesuai dengan hukum Lambert-Beer, dari nilai B atau gradient tersebut dapat dihitung nilai koefisien serapan molar (ε) dari sampel terhadap spektrum cahaya lampu pijar yang besarnya adalah 0,0242 M Sedangkan, untuk sumber lampu TL, grafik log intensitas rata-rata terdeteksi sebagai fungsi dari konsentrasi, disajikan dalam Gambar 5. Persamaan linear yang dihasilkan oleh perubahan konsentrasi larutan terhadap nilai log intensitas citra dengan sumber lampu pijar sesuai pada grafik adalah sebagai berikut, (4) Persamaan (4) Gambar 5. Grafik nilai log intensitas menurun sebagai fungsi konsentrasi sampel dengan sumber cahaya lampu TL.…”

Espectroscopia óptica de baixo custo: uma estratégia para a introdução de conceitos de física quântica no ensino médio

“…[19]. Também é reportada a utilização dos softwares Labview [20], RSpec [3], e MATLAB [21]. Para aquisição de espectros ópticos instantâneos, excelentes para demonstrações rápidas, existe a opção de instalar o software livre Theremino Spectrometer [22].…”

“…Devido à sua natureza interdisciplinar, esta técnica tem grandes potencialidades para integrar as áreas de Física, Química e Biologia. Além disso, favorece a inserção de atividades experimentais em ambientes formais de ensino [3]. Considerando seu custo elevado, não é plausível que instituições de educação básica adquiram um espectrômetro comercial.…”

Introducing spectrophotometry in the school lab employing LEGO bricks and LEDs

“…Nevertheless, their purchase costs remain particularly high, which makes the application of the corresponding laboratory techniques to the average school class essentially prohibitive. To this end, in recent years, the construction of simple DIY-type devices has been proposed, which significantly lowers the required cost (Albert, Todt, & Davis, 2012;Vanderveen, Martin, & Ooms, 2013). Moreover, some researchers have proposed the use of "smart" mobile phones as optical detectors (Kehoe & Penn, 2013;Knutson et al, 2015;Kuntzleman & Jacobson, 2016;Montangero, 2015;Morales, Confessor, & Gasparotto, 2015;Scheeline, 2010).…”