1. Transmission test for waveguide Hideyuki Sakamoto Tracker Phone Meeting, 25 th May,2006 Contents Method Measured luminosity Results and next step

2. Method Injecting green LED from the connector though a ND filter (making uniform light and adjusting light yield) and measuring light yield at the another connector by digital camera. –Green LED has 525 nm at peak –ND filter has 50 and 25 % transmission –Digital camera is used at manual mode with 8second(exposure) and 11mm(aperture). Estimating (relative) transmissions at each channels by calculating luminosity from each pixels. –Luminosity = 8/10bit value for Green component obtained from Raw data (array of RGB) recorded by digital camera. For checking the validity of this test, Old-type waveguide#9 was tested.

3. Setup Rolled Digital camera ND filter Green LED HV Supply Diffuser ～ 20cm Black Box Old-type waveguide MICE connector D0 connector For this test, D0 connector side is not fixed.

4. Measured luminosity Right picture shows that channels of small amount of luminosity corresponds to those found by reflecting light check. Converting Raw data into ascii file in order to estimate quantitatively. (not yet finished) Bad channels observed by reflecting light check #1 #2 #3 #8 #9 #10 #7 #6 #5 #4 Reflecting light check #10 #7 #6 #5 #4 #1

5. Result and next step It is found that this method is able to find bad channels and also estimate relative transmissions. Threshold for the transmission will be determined by this test with considering of efficiency, which is the criteria for selecting bad channels applied at the quality control. Bad channels observed is also checked by using beam data.