BUY SFH615A-4 https://www.utsource.net/itm/p/1086252.html
Optocoupler, High Reliability, 5300 VRMS
The SFH615A-4 is a 4-pin silicon photodiode from Siemens. It is designed for use in optical data communication systems and has a peak spectral sensitivity of 850 nm. The device has a high speed response and a low dark current. It is suitable for use in applications such as optical data communication systems, optical switches, and optical sensors. (For reference only)