July 2021 Laser Status: Green Laser Investigations
Investigations into the performance of green lasers in July 2021 reveal varying power amplitudes and actions taken to address issues such as low power output, replacement of laser components, and adjustments to timing and settings. Detailed analysis includes power measurements in April and June, replacement of the laser head and controller, as well as changes in fibre coupling and triggering modes. Additionally, insights into the performance of a blue laser (DP2-2) are provided, highlighting changes in attenuation settings and maintenance activities from April to July.
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
You are allowed to download the files provided on this website for personal or commercial use, subject to the condition that they are used lawfully. All files are the property of their respective owners.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author.
E N D
Presentation Transcript
Laser status July 2021 Green Laser: Power amplitude in April: around 750 ADC counts. Power amplitude in June: < 200 ADC counts. 1
Laser status July 2021 Green Laser investigation: 3) Replace the laser controller 1) Check the fibre coupling. Low power but no reference (never measured) With full green power (I=255): P(internal trigger mode) P= 83 mW P(external trigger mode) P= 9mW P after main coupling, P=37 mW. I Loss = 3.5dB Power internal trigger mode direct output of the laser : P= 16mW P after coupling fibre+10m fibre : P= 5mW I Loss = 5dB Power with external trigger mode , direct output : P=1.7mW re-adjust NIM_DELAY: 7901 to 7893 (100ns) NIM_DELAY can be fine tune by 12.5ns : 7885 to 7886 2) Replace the laser head with the old one from 2018 (laser replacement in 2018 because of faulty controller) P(internal mode, direct output) P= 50mW P(external trigger mode) P after main coupling, P=21 mW. I Loss = 3.5dB Adjust NIM_DELAY for the timing : -200ns from fast monitoring so NIM_DELAY should be reduced from 7901 to 7885. P = 8mW Pulse on the matacq better but still too low 2
Laser status July 2021 Green Laser: - Laser head replaced by the one in used from the beginning, before 2018 (this could explain the power lower than before) - New laser controller. The 2nd one after 2018. 06/05/2021 3
Laser status July 2021 Blue Laser DP2-2: In APRIL In July after the maintenance in May In April: 35A and 50% internal attenuation instead of 35 % . That s why maintenance was needed. In July: 35A and 35% internal attenuation. The remote attenuator has been changed on dBGUI to reduce the EB power : 9 to 6% Ps: In June it was still the test with long fibre TTCci so not the same configuration 4
