positive comes from the battery,
through the spring to the driver
from the driver into the positive pin on the diode
through the crystal to the negative pin on the diode
out the negative pin into the case of the diode
from the case into the body of the laser
from the body of the laser through the switch
from the switch into the battery contact spring
from the spring back into the negative side of the battery
Voila! A complete circuit
The body of the laser serves as the negative "wire" in the circuit
In the flexdrive itself, the negative "in" and the negative "out" are continuous. They are physically connected. A negative connection at one end of the driver also serves to make the negative connection at the other end of the driver. Since they are physically connected, it is unnecessary to have a "wire" attached to both ends. You have to have the negative end hooked to the diode so it makes sense to have that end be the one connected to the case. When the case of the laser serves as the negative pathway, there is no need to have a "wire" attached to the "in" side of the flexdrive. It gets it from the case.
My next question: Is this true for Phr803T and the Open Can red?
In other words, are these 2 LDs negative connected to the case?
I know the Open Can red must be as it was my original installation but not sure for the phr803t...