I am using the CNY70 for a project, but i need information from the datasheet. In Figure 11, which i have added below, the relative collector current, \$I_{Crel}\$, is shown versus the displacement, s, for six different distances, d.
As i understand, d is a measure for the distance between the reflective sensors emitter and the reflective surface, as shown in the image in the upper right corner of fig. 11. But i can't seem to find a description of the displacement s. From the image, it seems as if the displacement s, is the distance from the center of the CNY70 to some surface perpendicular to the reflective surface. But that does not make any sense at all.
I hope I have provided enough information. Thanks in advance.
Sorry if i left something out, i am new here and in the field of electrical engineering.
Best Answer
Figure 1. The graph is scaled in an unusual manner.
If I was doing this graph I probably would have used 0 as "edge on centre of target" and then used +/-5 mm for the adjustment. These guys are saying that 0 is covered with 5 mm beyond centreline.
As we might expect we get 50% current when the target edge is on the centreline as half the maximum light will be reflected.
The various curves are a function of the beam angle. The closer the target, the narrower the beam and so full or zero light is reflected with a smaller deviation in 's' from the centreline.