- Five pieces of the OSEM coil bodies (wires are wounded) are washed with acetone in a ultrasonic bath (40degC, 20mins). The wires' edges are not fixed to the coil body because Takahashi-san pointed out that the vac seal could be removed by acetone.
- A PD(S1223-01) and a LED (TSTS7100) are also washed in the same manner. I'll check if their performance would decrease (increase?) or not.
Results
Conditions:
- The washed and non-washed PDs are different ones.
- The same LED's intensity noises are measured before and after the wash.
The attached graph shows the washing would not affect the performance; it's only one sample, so we still lack a statistics, but we can probably say they can tolerate the ultrasonic washing.
About the PDs, noises with PDs are the same level as the 35670A at their inpur ranges. The mechanism why the input ranges are different for the two measurements are unknown, but one thing: the Okt circuit and LEDs and PDs are connected by crocodile clips (alligator clip, whatever), and the noise level is very senstive to the arrangement of these wires!
According to the graph, it appears the washed one becomes better than unwashed one, but the measurement are the same level as the measurement noises, so we cannot say such things.
