Source google image: https://www.researchgate.net/profile/Chin-Hui_Chen2/publication/280778036/figure/fig1/AS:391534580125696@1470360526031/a-Microscope-image-of-a-5-channel-photonic-transmitter-High-speed-modulation-are_Q320.jpg
S&s isolationen gmbh
Source google image: https://www.researchgate.net/profile/Chin-Hui_Chen2/publication/280778036/figure/fig1/AS:391534580125696@1470360526031/a-Microscope-image-of-a-5-channel-photonic-transmitter-High-speed-modulation-are_Q320.jpg