Belušič Gregor, Ilić Marko, Meglič Andrej, Pirih Primož
Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia.
Sokendai (The Graduate University of Advanced Studies), Hayama, Kanagawa, Japan.
Sci Rep. 2016 Aug 25;6:32012. doi: 10.1038/srep32012.
Optical experiments often require fast-switching light sources with adjustable bandwidths and intensities. We constructed a wavelength combiner based on a reflective planar diffraction grating and light emitting diodes with emission peaks from 350 to 630 nm that were positioned at the angles corresponding to the first diffraction order of the reversed beam. The combined output beam was launched into a fibre. The spacing between 22 equally wide spectral bands was about 15 nm. The time resolution of the pulse-width modulation drivers was 1 ms. The source was validated with a fast intracellular measurement of the spectral sensitivity of blowfly photoreceptors. In hyperspectral imaging of Xenopus skin circulation, the wavelength resolution was adequate to resolve haemoglobin absorption spectra. The device contains no moving parts, has low stray light and is intrinsically capable of multi-band output. Possible applications include visual physiology, biomedical optics, microscopy and spectroscopy.
光学实验通常需要具有可调带宽和强度的快速切换光源。我们基于反射平面衍射光栅和发光二极管构建了一个波长组合器，这些发光二极管的发射峰值在350至630纳米之间，它们被放置在与反向光束的一级衍射相对应的角度。组合后的输出光束被发射到一根光纤中。22个等宽光谱带之间的间距约为15纳米。脉宽调制驱动器的时间分辨率为1毫秒。该光源通过对家蝇光感受器光谱灵敏度的快速细胞内测量得到了验证。在非洲爪蟾皮肤循环的高光谱成像中，波长分辨率足以分辨血红蛋白吸收光谱。该设备没有移动部件，杂散光低，并且本质上能够进行多波段输出。可能的应用包括视觉生理学、生物医学光学、显微镜学和光谱学。
