Fig. 1. Schematic representation of the structure of optical stimulation system

Fig. 2. Software interface of the host computer

Fig. 3. Photo of baseplate of optrode

Fig. 4. Welding process of μLED chip. (a) Photo of μLED chip; (b) μLED chip with solder paste; (c) successfully welded single μLED; (d) photo of whole optrode module

Fig. 5. Flowchart of program of stimulator

Fig. 6. Photograph of optical stimulator and optrode

Fig. 7. Relationship between output optical power and distance and the number of open channel. (a) Relationship between output optical power and distance; (b) relationship between output optical power and the number of open channel

Fig. 8. Relationship between output optical power and running time

Fig. 9. Output waveforms of stimulator under different standard frequency values. (a) 1 Hz; (b) 50 Hz; (c) 250 Hz; (d) 500 Hz

Fig. 10. Relationship between standard frequency and output frequency or error

Fig. 11. Relationship between packet loss rate and distance of wireless communication

Fig. 12. Testing of multichannel of optrode. (a) Channel 1 is open; (b) channel 2 is open; (c) channel 3 is open; (d) channel 4 is open; (e) channel 5 is open; (f) channel 6 is open; (g) channels 1,3,and 5 are open; (h) channels 2, 4, and 6 are open; (i) all channels are open