I have a question about the OPT101. The data sheet gives the following information: Current responsivity: 0.45 A/W or 865 (µA/W)/cm². I don't quite understand how the value of 865 (µA/W)/cm² is calculated. By converting 0.45 A/W to the area of the OPT101, I get 8650000 µA/W/cm². Can you help me?