Onefive Origami 33MHz specs, posted by Loïc Amoudry at Optical room about lasers and optics 6x
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Power during ~20h, power after turn on, spectrum image and excel datas, polarisation and pulse length.
Powermeter measurments were done with a /10 filter.. 3 mW means 30 mW
Important: Onefive does not automatically locks after being turned on. |
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Onefive Origami 33MHz specs - Polarisation, posted by Ronic Chiche at Optical room about lasers and optics
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one rotate a lambda/2 before a PBS and meausure the refected power:
Pmax=35.6 mW
Pmin=107 µW |
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Mirrors checked with binocular microscope, posted by Loïc Amoudry at Optical room about lasers and optics
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29/01/19 - ThomX mirrors have also been checked with binocular microscope. They shown the same spots as S-BOX mirrors.
1st image shows reflective face of a spherical mirror.
2nd image shows reflective face of M1 (sapphire). |
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Mirrors sent to LMA, posted by Loïc Amoudry at Other about lasers and optics
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30/01/19 - As LMA people came, we discussed about the spots on ThomX mirrors which should be clean. As mentionned in "SBOX commissioning",
these spots are normal.
An other question appeared during the conversation about the storage time and location of these mirrors. They have been stored for more than |
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Beam size and finesse, posted by Loïc Amoudry at Optical room about lasers and optics
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FSR initiale : 33.34 MHz (S3 = -825000 et S4 = -825000)
Beam size initiale : wx=2.05mm et wy=2.15mm
Finesse initiale : 3400 |
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Check of mirrors and coating directions, posted by Loïc Amoudry at Optical room about lasers and optics
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Direction of HR face of P1 and P4 have been checked, there was no problem. The mirrors are in the good direction and the coating is on the good face.
Once P1 and P4 outside of the cavity, we checked the coating position by sending the HeNe laser with an angle. There was two reflections and
the most intense was the one closer to the normal to the mirror. |
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Finesse after removing wires, posted by Loïc Amoudry at Optical room about lasers and optics
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19/04/01: We removed the wires from the beam path in the cavity. Finesse stayed at 3400. FSR: 33.342 MHz.
When locked:
Input Power: ~4mW |
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Transmission of the mirrors, posted by Loïc Amoudry at Optical room about lasers and optics
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We openned the cavity, removed S2 and measured trans of P1 and same for S2.
Pin ~= 3.91 mW
PS2 ~= 20 nW --> ~~ 5 ppm !!! |
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Beam size at closest spherical mirrors position, posted by Loïc Amoudry at Optical room about lasers and optics
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S3 and S2 @ +1 640 000 and P1 and P4 @ -825 000
Diameter in x: 4.7mm
Diameter in y: 4.7mm |
Transmission of the mirrors, posted by Loïc Amoudry at Optical room about lasers and optics
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After verification, transmission of P1 correspond to ~150ppm.
The 1337ppm come from a beam leakage. Reflection from P1 goes to the input window which reflects again a part of the beam directly into the cavity
between P1 and S3 then between P4 and S2. |
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Transmission of the mirrors, posted by Loïc Amoudry at Optical room about lasers and optics
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P1 transmission out of the mount (means angle of the mirror is not the real angle):
Pin = 3.2 mW
Pout = 545 nW |
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Finesse with P1 SUPRASIL, posted by Loïc Amoudry at Optical room about lasers and optics
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P1 SUPRASIL has been installed instead of P1 Sapphire. It has been cleaned 3 times on each face with wipe+isopropanol before to be installed.
Finesse ~= 10 000 - 11 000 (EOM Sweep of 100 kHz in 10sec, see last image.)
Coupling ~= 45% |
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Finesse after 2days, posted by Loïc Amoudry at Optical room about lasers and optics
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Finesse measured this morning after P1 SUPRASIL being into the cavity for two days. In order to check if it's getting dirty.
Finesse still ~= 11 000 |
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P4 cleaned and finesse measurement, posted by Loïc Amoudry at Optical room about lasers and optics
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P4 cleaned with isopropanol.
Finesse measured afterward: ~=13 000 (clear increase) |
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Mirror's cleaning and finesse, posted by Loïc Amoudry at Optical room about lasers and optics
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Summary of what have been cleaned the last week:
P1 with isopropanol, finesse 11000
P4 with isopropanol, finesse 13000 |
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Injection of 33MHz Onefive through fiber, posted by Loïc Amoudry at Optical room about lasers and optics
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Output power of the Onefive, and power after injection and different components have been measured.
Coupling ~= 90%
Each of our two EOM roughly have the same loses ~3dB |
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33MHz Onefive power overtime decrease, posted by Loïc Amoudry at Optical room about lasers and optics
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Power of the 33MHz Onfive decreases over time. Have to pay attention to that.
Note that air dryers have never been stopped.
10th april 2018: ~40mW (first picture, 10dB filter) |
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New Suprasil mirror from LMA, posted by Loïc Amoudry at Optical room about lasers and optics
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14/05/19:
New Suprasil mirror received. It will replace the S-BOX suprasil mirror on ThomX which was already replacing the sapphire mirror.
First finesse measurement: 14000 |
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Finesse after cleaning (new suprasil mirror), posted by Loïc Amoudry at Optical room about lasers and optics
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15/05/19-20/05/19:
Cleaning of the mirrors:
Initial finesse 14000 @air |
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Finesse measurement by decay time technique, posted by Ronic Chiche at Optical room about lasers and optics
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5 Files attached:
- Note on the technique and results for the present cavity on 2019, May 21th : F ~ 18 000
- 2Tektronix scope raw data |