title: Home-made N-channel fiber-optic spectrometer from a web camera.
abstract: This paper demonstrates the high potential of a web camera to be utilized as a low-cost multichannel fiber-optic spectrometer suitable for either educational or quality-control purposes in small and medium enterprises. The key idea is to arrange N input optical fibers in a line  and position an external dispersive element to separate incoming optical beams into their associated spectral components in a two-dimensional (2D) space. With a commercial web camera, each set of the spectral components is imaged through a plastic lens onto the 2D image sensor of the web camera.  For the demonstration, a five-channel webcam-based fiber-optic spectrometer is implemented where each channel is calibrated by selected reference light sources. The constructed spectrometer can perform wavelength analysis of the spectral irradiance in the range of 400 to 655 nm. Experimental  results also show that peak operating wavelengths of five light-emitting diodes and a laser pointer can be determined with a wavelength measurement error of less than 10.5 nm. The total cost of the webcam-based five-channel fiber-optic spectrometer is only approximately US$92.50 and  effectively performs to the desired results.
authors.affiliation: Intelligent Devices and Systems Research Unit, National Electronics and Computer Technology Center, 112 Thailand Science Park, Phahonyothin Rd., Klong 1, Klong Luang, Pathumthani 12120, Thailand. sarun.sumriddetchkajorn@nectec.or.th
authors.forename: Sarun
authors.initials: S
authors.lastname: Sumriddetchkajorn
authors.forename: Yuttana
authors.initials: Y
authors.lastname: Intaravanne
mesh_terms: D002138:Calibration; D004867:Equipment Design; D005336:Fiber Optic Technology / Q000295:instrumentation*; D006696:Holography / Q000295:instrumentation; D007091:Image Processing, Computer-Assisted; D020407:Internet / Q000295:instrumentation*; D013057:Spectrum Analysis / Q000295:instrumentation* / Q000379:methods*