Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics 
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yesterday morning with Manar,
1) we fixed the threshold level of the laser input signal which makes the measurement of the repetition rate.
(if the rep rate is not measured properly, the amplifier safety interlock stops immediately the amplification). |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics
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this morning with Manar,
- we checked first the chiller problem.
the fluctations of +/-2° around 25°C are still there. |
Alphanov amplifier beam profile Data , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics 8x
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Adding the schematic of the measurements.,
the 4° Beam Deviation, AR Coating ( B coating)
The 3 data points taken of the beam profile are fitted in Gaussian Beam with taking the beam waist at the output of the compressor box. |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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Today with Ronic
For the Temperature fluctuation :
we checked the valves of the tubes bumping water into the chiller from ThomX main water supply, they were |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics
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this morning with Manar,
- we fixed the chiller problem (+/-2°C fluctuation around the set temperature value = 25°C).
we opened and closed several times the water valve of the primary circuit to remove air bubles => no effect on the temperature variations. |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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Ronic on Friday operated the Amplifier from the Alphanov software, switched it off then turned on the LAL software,
and it worked for 40 min without issues or error appearing,
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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the laser amplifier worked for some days but it ended to a "watchdog" alarm which switches off the amplifier... investigation is ongoing
Ronic
Chiche wrote:
Ronic on Friday operated the Amplifier from the Alphanov software, |
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Alphanov amplifier beam profile Data , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics
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This Morning with Victor the amplifier was turned on @ 20% amplification (output ~ 9 W ) for approximately 3 hours and no error appeared.
I took data of the beam profile at different points without a lens after the 2 wedges
@ 0% (only pump beam), output ~ 300 mW (taken from previous data) , output after 2 wedges 2.2 uW |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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we have had this new issue (watchdog alarm switching off the amplifier) for several days.
Alphanov mentionned it could come from the input oscillator stability (modelock loss for example).
Today, |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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With Daniele after, we took a readings of the beam with a lens of 750 mm.
From the observed data, we can state that the beam is not completely Gaussian M2 > 1, due to the variation of the ellipticity of the beam
along the focused path |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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This morning,
- with the "Alphanov" software => Central panel => "system" button => Watchdog "Period Max" was at 100ns
and has been set to 200ns. |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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This morning with Daniele, we did a second measurement of the beam profile using a different lens of focal 400 mm.
at a power amplification of 20%
the amplifier stayed on for around one hour and a half with no errors. |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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On Monday 20th of February, Daniele and Viktor took some beam profile measurement data @ 50% of power amplification.
data and analysis can be found in the attached file.
Ronic |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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Yesterday, Guillaume Machinet and Vincent Clet from Alphanov came to fixe some issues with the laser amplifier:
- 1) they fixed the "rep. rate" measurement issue.
previously, the voltage range in which it was possible to detect the correct rep rate (33MHz) was very narrow ~ 50mV. |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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This morning with Victor we took a reading of the beam profile using a 400 mm lens at 70 % and 100 % amplification.
Will process the data and add after
Note : after an hour and half of amplifier on at 70% we increased the power to 100%, and after ~ 10 minutes the amplifier turned off and showed |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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this morning with Manar,
we checked the Alphanov amplifier issue : "The laser has been stopped because its power is too far from the nominal power".
the photodiode voltage measuring the output power has drifted again and then, the estimated output power was wrong, triggering an alarm issue. |
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CW laser installation and cleaning, posted by Ronic Chiche at ThomX igloo about lasers and optics
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This morning with Manar, in order to prepare the installation of the news FP cavity mirrors,
- we installed the Koheras below the optical table
- we put a fiber prolongator at the end of the Koheras fiber and we put a mounted collimator at the end of the fiber. |
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CW laser installation and cleaning, posted by Ronic Chiche at ThomX igloo about lasers and optics
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This morning with Ronic , in preparation for the mirror installation, we removed additional mechanics and cables from the table.
We organized and cleaned the permanently installed cables on the table away from the area of the cavity opening.
We opened the two top vents and left the shutters open to circulate clean air , (note the shutters surrounding the laser and amplifier are half |
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Alphanov amplifier beam profile measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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We took reading of the beam profile of the amplifier without a lens @ 30 cm from the 2nd wedge for amplification percentages
20-30-40-50-60-70-80-90-100 % another additional 3 readings will be taken at different locations for all amplification percentages.
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Amplifier Beam Profile over time , posted by Manar Amer at ThomX igloo about lasers and optics | detectors and electronics
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This morning, with Ronic, we opened the compressor box to observe if there is any misalignment of the mounts or the CVBG's
a comparison slide between the Beam Profile over time and measurements we have taken, is included.
we noticed
today that the images need a rotation, and I took the assumption we did not rotate last year and did the rotation of the previous images.
Comparing |