These graphs show some typical output signals as an opaque object blocks the light as it passes through the slot. All the data was collected from an OPB370N51, which has a .050”x.060” aperture over the emitter and a .010”x.060” aperture over the sensor. The orange lines represent the output current response as an opaque flag is lowered from above. The green lines represent the output response as a flag is brought in from the left. These two responses are different because the aperture is longer vertically than it is wide. The final line, blue, represents the current response as an object moves across the device from the right. The top left graph represents the flag blocking the light beam when close to the emitter; the top right has the flag close to the sensor; and the bottom left shows the flag in the middle of the slot. Remember, the aperture from the top is always the widest and the aperture from the sides can be adjusted.